Week 2 DB: Conception/Fertilization and 1st Trimester Scanning

 
 
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Hormonal Influences to Fertilization
by Michelle Wilson - Monday, 4 January 2021, 1:57 PM
 

Discuss the importance of different hormones during the implantation and cleavage process. In your opinion, is one more important than another

 
Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Monday, 11 January 2021, 6:38 PM
 

Hi Classmates!  Personally, in the past I didn't think discussion boards helped me learn and I thought of them as more of busy work than a learning tool. However, after hearing what Dr. Wilson and Paris said made me want to give DB an honest try and hopefully get more out of it. And what better time to try it, than this week! 

I, like a lot of us in class, am a visual learner so maybe we can include visual aids in this DB that helped each other with this concept. 

Let's all challenge each others thoughts and hopefully teach each other more about conception and the first trimester. 

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Monday, 11 January 2021, 7:07 PM
 

To start off the DB, the corpus luteum plays an important role in implantation as it secrets progesterone for the uterus to prepare for implantation (decidualization). However, the rising levels of estrogen also plays a role in the initial growth of the endometrium. If there was no progesterone there wouldn't be a thick endometrium for the egg to burrow in. Another hormone that is related to implantation is human chorionic gonadotropin (hcG) that is released when the blastocyst embeds in the endometrium.  The hcG helps the growth of the corpus luteum which then produces progesterone, making sure the uterus is nice and plump for the blastocyst.  I would say the progesterone is the most important hormone out of all of them even though they all work together and conception couldn't happen without the other. If we didn't have progesterone then the functional layer would shed causing menstration and make it difficult for the egg to implant. 

 

Ultrasound showing normal IUP as shown by the double decidual rings and presence of a yolk sac in a gestational sachttps://www.youtube.com/watch?v=kWHAzsYec6o

Picture of Lania Black
Re: Hormonal Influences to Fertilization
by Lania Black - Tuesday, 12 January 2021, 7:26 PM
 

Hi Candee, I love the image and YouTube video you linked! I totally agree with you about progesterone, it has to be secreted in order for the egg to even has a nice, comfy, plush endometrium to live in. So progesterone is SUPER important! But I couldn't help think that all of them are equally as important. If any of these hormone fail they could cause the pregnancy to be unsuccessful, despite progesterone doing its job initially. Let's say progesterone was secreted normally but then later on maybe the estrogen is secreted properly which is vital to the baby's proper development of their organs. This could be a major issue! So with that being said, I think they're all equally important.

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Re: Hormonal Influences to Fertilization
by Karen Chow - Thursday, 14 January 2021, 7:42 PM
 

Hi Candee, 

I agree with you in the sense that if we HAD to pick the most important hormone, I'd probably pick progesterone as well. But we could argue that ovulation is important or we wouldn't even be talking about any kind of implantation. Chicken first or the egg kind of argument, really. 

Loving the term plump for a good uterus!

 

Karen

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Monday, 11 January 2021, 9:21 PM
 

Hormones play a very important role in early pregnancy. My initial reaction is that no one hormone is more important than the other in this process, because if even one thing is wrong/missing, the pregnancy likely won't be successful.

The first one that pops into my head when discussing implantation is progesterone -- promote gestation! This is secreted by the corpus luteum in the ovary after ovulation. By secreting progesterone, the corpus luteum is ensuring we have a nice plump pillow for the blastocyst to land in when it reaches the uterus. Estrogen also helps with endometrial thickening, although we see higher estrogen levels prior to ovulation as that is what the developing Graafian follicle is secreting. We will see more estrogen from the placenta, but that occurs after implantation.

The other big pregnancy hormone is hCG (human chorionic gonadotropin). Big surprise, it comes from the chorion, specifically the trophoblast cells. hCG helps extend the life of the corpus luteum, which means more progesterone for a better endometrial burrow for the embryo.

If you remove either of these from the equation, you won't get the endometrium you need to catch and maintain the blastocyst/embryo.

Picture of Sarah Swager
Re: Hormonal Influences to Fertilization
by Sarah Swager - Tuesday, 12 January 2021, 6:47 PM
 

Leah,

 

I agree that all of the hormones are essential for a successful pregnancy and no one hormone is more important than another. Additionally, I'd like to add that without GNRH none of these other hormones would have been released in the first place. Thanks, hypothalamus! This is a little reminder from last quarter.

 

 

 

Sarah

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Tuesday, 12 January 2021, 10:27 PM
 

Hi Leah! I also said the essential progesterone, estrogen, and hcG. Your answer is straightforward and completely answers the question. Did you find anything about the cleavage process? I know you're a very visual learner, if you find any resources please share!

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Wednesday, 13 January 2021, 12:19 PM
 

Hi Candee,

I was unable to find anything decisive about hormones related to cleavage. However I did come across this chart:

pregnancy hormones

So I did some more research on hPL, and posted a response to Zuly with the quick summary. Because it is produced by the placenta, it is more for after implantation once the placenta has developed.

I also like this chart because it shows how the placenta takes over progesterone production after the corpus luteum regresses around week 10.

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Wednesday, 13 January 2021, 12:31 PM
 

Another resource for visual learners:

https://www.youtube.com/watch?v=z71eDEUT8Bc

Nice animation of cleavage and implantation with THE MOST DRAMATIC MUSIC!

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 6:28 PM
 

Thank you for adding these! The dramatic music really helps my learning

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Wednesday, 13 January 2021, 12:38 PM
 

Apologies for all the extra posts! I just came across this slide online. It suggests progesterone from the corpus luteum helps the zygote develop? I'm doing some additional research to see if I can confirm this, but if anyone finds something, please post!

Picture of Hailey Indelicato
Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 5:58 PM
 

Hi Leah,

this is an interesting point, i just looked into it and i can't find anything that says that, only that progesterone helps with development of the embryo. this could be a question for Paris or Dr. Wilson!! great find.

Picture of Nailah Hollman
Re: Hormonal Influences to Fertilization
by Nailah Hollman - Thursday, 14 January 2021, 11:42 AM
 

Hello Ms. Leah, 

 I really liked your analogy of a nice plump pillow for the blastocyst to implantation. Considering progesterone’s main function is to make the uterus comfortable just as pillow does for the body. I definitely can‘t forget that analog. I will say I also found it interesting how estrogen plays a role in the cervix and vagina as well to assist sperm on its voyage to the uterus. 
Here is the information if you are interested in reading more about it: 

 https://www.khanacademy.org/test-prep/mcat/cells/embryology/a/egg-meets-sperm

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Thursday, 14 January 2021, 5:58 PM
 

Thank you Nailah!

Picture of Chrishawna Porter
Re: Hormonal Influences to Fertilization
by Chrishawna Porter - Monday, 11 January 2021, 10:13 PM
 

When most people think of pregnancy, chances are their first thought is not about hormones, but more so the miracle of life. I think of hormones as the base of all things pregnancy related. They are what set the stage for what is to come over the next 9 months, so it is important to understand how they function and interact with one another. Before we can become anything more than a twinkle in our parents' eye we must lay down the groundwork. In gynecology, we learned the importance of the hypothalamus secreting GnRH to act on the anterior pituitary to eventually release LH and FSH, which will trigger the ovaries to release a few hormones of its own, estrogen and progesterone. Prior to implantation we must have ovulation, fertilization, cleavage, and blastulation which essentially means our hormones will be put to work. During implantation we rely on the syncytiotrophoblast to release the pregnancy hormone hCG. This is critical as it will prompt the corpus luteum to continue secreting progesterone to keep the endometrium thickened and prevent both the functional layer and blastocyst from being sloughed off. It's similar to a game of telephone, if the syncytiotrophoblast doesn't get the right message to the corpus luteum the pregnancy is lost and in this case so is the game! And last but not least we have estrogen, which helps ready the endometrium along the women's menstrual cycle so it may be thick enough if fertilization is to occur. I don't believe any hormone is more important over another as they seem to rely on each other. Hormones are essentially small pieces that when put together create an amazing puzzle! If anyone has any information on what is happening hormonally during the cleavage process, please share, I didn't find any credible information in my research!

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Re: Hormonal Influences to Fertilization
by Brittany Lopes - Tuesday, 12 January 2021, 12:30 PM
 

Hi Chrishawna!

I agree with you that I also couldn't find any specific hormones linked to cleavage. However, my best guess is that since cleavage is happening in conjunction with endometrial preparation, the main hormone is just progesterone from the corpus luteum. Remember, after ovulation the ovum is fertilized in the fallopian tube and begins cleavage there. Also at this time the ruptured follicle becomes the corpus luteum and starts secreting progesterone. Here's a little graphic which may help with visualization! Sorry I couldn't be of too much assistance but I hope this helps a little!


Picture of Chrishawna Porter
Re: Hormonal Influences to Fertilization
by Chrishawna Porter - Friday, 15 January 2021, 7:07 PM
 

Hi Brittany!

I think the image you have shared does the best job of explaining the ovulation and fertilization process. I really like having all hormonal aspects of the process in one solitary image. With that being said I have been researching throughout the week on the hormones (if any) present during cleavage but unfortunately I have still come up short! This is definitely something I would like to as Dr. Wilson and Paris about!

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Re: Hormonal Influences to Fertilization
by Candee Lam - Tuesday, 12 January 2021, 10:31 PM
 

Thank you for adding a beautiful picture that represents the growth of a fetus with hormones. I liked that you added LH and FSH to your topic because we forget that the ovaries play an important role that lead up to the egg being released. I did't find anything specific on cleavage but thought that estrogen and hcG play a big roll in division. Maybe the hormone that is in control of mitosis is in control of mitosis, if thats a possibility? Let me know your thoughts! 

Picture of Chrishawna Porter
Re: Hormonal Influences to Fertilization
by Chrishawna Porter - Wednesday, 13 January 2021, 10:16 AM
 

Hi Candee!

You pose an interesting question on what is in control of mitosis. We know that the zygote is not going to undergo cleavage simply on its own, so there must be a driving force behind it. With that being said, my research on this topic led me in circles. Some sites recognized cleavage and mitosis as separate productions while others say, cleavage is a form of mitosis. This topic was pretty confusing, but it seems like cleavage could potentially be a form of mitosis just sped up and doesn't allow for growth as mitosis typically does. Also it seems that the process is enzyme based and not hormone! I found a graphic that shows both processes, but again, it is up for interpretation!

Cleavage vs Mitosis

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Re: Hormonal Influences to Fertilization
by Allison Wine - Tuesday, 12 January 2021, 10:02 AM
 

Hormones are the key factors that contribute to a woman's ability not only conceive but also to carry the pregnancy to term. As you can see from the graph below (the 2 right columns) LH, FHS and Estrogen are prominent in the follicular phase of a woman's cycle. They stimulate follicle growth and release of the follicle into the fallopian tube. After ovulation progesterone is secreted from the Corpus Luteum which tells the uterine lining to thicken (aka creates the best home) for the incoming blastocyst. Once the blastocyst implants itself into the uterine lining the trophoblast cells release the hormone HCG into the mother's system. That HCG communicates back to the Corpus Luteum that fertilization has occurred and that the uterine lining needs to stay thickened. Thus, progesterone production increases and the decidualization process of the endometrial tissue should begin to support the embryo.

In my opinion I believe all hormones involved are very important. For example, If in the follicular phase of a woman's cycle there is too much of one or more hormones or not enough she may not even have a mature follicle to release an ovum. Therefore, fertilization does not occur. Conversely, let's say the first half of the cycle goes smoothly and the ovum is fertilized but the woman's progesterone response is poor then the blastocyst that has formed now doesn't have the ideal lining to attach to and therefore may result in failed implantation. Lastly, we can say everything goes smoothly in the beginning, ovulation occurs, the ovum is fertilized, the uterine lining is thick and 5- 10 days later implants into the uterus however does not secrete HCG. The corpus luteum would not get the signal that there is a pregnancy, progesterone levels would eventually decrease the lining would shed and the blastocyst would not have the proper environment to prosper.

 

 

Implantation , embryology_and_placental_development

 

 

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Re: Hormonal Influences to Fertilization
by Candee Lam - Tuesday, 12 January 2021, 10:36 PM
 

Hi Allison 

Thank you for sharing your great visual, I see that picture in the book and our lectures and it is still helps me every time I refer to it. I remember in our last lecture for GYN when we discussed IVF, ZIFT, etc. you talked about a few hormones that were given to women to help with implantation. Do you remember what those were? 

It might be Clomid (this the drug made to increase estrogen?)

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Re: Hormonal Influences to Fertilization
by Allison Wine - Wednesday, 13 January 2021, 9:01 AM
 

Hey Candee,

 

Fertility medications go into a lot of detail more so in the beginning of the follicular phase of the menstral cycle. To clarify Clomid and Femara basically tell the brain to produce FSH so follicles will mature and a follicle will grow into a Graaffian follicle. For some women like me with PCOS, we have high levels of estrogen and LH in the follicular phase of the cycle and low FSH. Therefore a dominant follicle has a hard time forming. If the body doesn‘t respond to those medications, medications like Follistim (injection) could be used. This medication basically skips the brain and puts FSH straight into the system. Therefore follicles will start to mature. Then oddly enough HCG is used to trigger ovulation. Not sure how that works. Sometimes if a woman’s endometrial lining is measuring low progesterone will be given To thicken the lining. This is all a bit over what we are learning but definitely helps emphasize what is normal and what can go wrong. Hormones are very important!! 

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Re: Hormonal Influences to Fertilization
by Brittany Lopes - Tuesday, 12 January 2021, 11:51 AM
 

Hormones are the driving factor before, during, and after a pregnancy. They work together as a synchronous team to ensure that the body can support an embryo, and that the embryo will develop correctly. When follicles are developing in the ovary they begin secreting estrogen. When estrogen levels are high, this signals for luteinizing hormone (LH) to be secreted from the anterior pituitary gland. The LH surge is responsible for ovulation. Skipping forward in a woman's cycle to post ovulation, the ruptured follicle is now a corpus luteum and begins to secrete progesterone. Progesterone is extremely important in developing and maintaining the endometrium, otherwise known as decidualization. This hormone allows the endometrium to grow thick and provide a good environment for the blastocyst.

Once the blastocyst loses its zona pellucida and begins to implant into the endometrium, the trophoblast cells start secreting human chorionic gonadotropin. This hormone maintains the corpus luteum so it can continue to secrete progesterone until the placenta can take over. Human chorionic gonadotropin is also the hormone that is measured to determine if a woman is pregnant. 

While there are several hormones that are needed during a pregnancy, I believe that progesterone is the most important one. Without this hormone the endometrium will not grow to be nice and thick and instead the low levels will cause menstruation to begin and the endometrium to be sloughed off. This can be a tragic event because the blastocyst will either not be able to implant, or it may implant but the low levels may cause the lining to shed, therefore causing a spontaneous abortion.

Picture of Allison Wine
Re: Hormonal Influences to Fertilization
by Allison Wine - Wednesday, 13 January 2021, 2:05 PM
 

Hey Brittany,

I agree progesterone is very important hormone that needs to be secreted in order for implantation to occur. Women with a luteal phase defect often have low progesterone and therefore a suboptimal endometrial lining for implantation. With a luteal phase defect either the ovaries don't secrete enough progesterone or the lining of the uterus does not respond to the hormone and usually the luteal phase lasts 8 days or less. Which as we gathered in class implantation may not even have occurred and the uterus lining starts to shed. Also an interesting article goes into detail claiming a endometrium thickness less than 7mm has a thin or absent functional layer which means the embryo is much closer to the spiral arteries. The spiral arteries have a higher oxygen concentration which is detrimental to the embryo.

https://www.inviafertility.com/blog/blog/infertility/drvkarande/optimizing-implantation-why-does-a-thin-endometrium-uterine-lining-

Great job! I would also add FSH along with estrogen signal the follicles to go in the follicular phase of the cycle. 

 

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Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 6:53 PM
 

Hi Britt Bratt!! I liked your answer and liked that you included the process for spontaneous abortion. Since you are talking about things that could go wrong during the first trimester, what are some other things that could possibly go wrong during the first trimester?

Picture of Brittany Lopes
Re: Hormonal Influences to Fertilization
by Brittany Lopes - Thursday, 14 January 2021, 5:25 PM
 

Hey girl hey!

The first trimester during pregnancy is an extremely fragile time. This is the time where miscarriage risk is highest and when structural anomalies can form. Some examples of structural anomalies are anencephaly, club feet, and spina bifida. These can be really heartbreaking anomalies to see and I look forward to learning how to spot them so I never miss it.

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Re: Hormonal Influences to Fertilization
by Lauren Brodehl - Tuesday, 12 January 2021, 12:44 PM
 

The most important hormones at work during implantation and cleavage are estrogen, progesterone, and human chorionic gonadotropin (HCG). Initially, estrogen causes the pituitary gland to release luteinizing hormone, triggering a single ovarian follicle to to release an egg (ovum). This ruptured follicle is now considered a corpus luteum, and secretes progesterone. At ovulation, estrogen initially thickens the endometrium, preparing it for a possible zygote. Once the egg is released, progesterone maintains endometrial thickness throughout the pregnancy and the functional layer of the endometrium is not shed if a zygote successfully implants. HCG, produced by trophoblast cells, extends the life of the corpus luteum so that it continues to secrete progesterone. 

I cannot find information on the hormones related to cleavage, but that the sperm activates the divisions to begin about 24-30 hours after fertilization. I would love to hopefully understand more of what drives the divisions to begin!

I don't believe one can say firmly which hormone is most important to a pregnancy. They all work together to prepare the endometrium to carry a pregnancy for 9 months. Without estrogen, the endometrium would never get to the point it needs to be for progesterone to take over, and without HCG, progesterone would fall back down, causing the functional endometrium to slough and lose the pregnancy.

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Re: Hormonal Influences to Fertilization
by Sarah Swager - Tuesday, 12 January 2021, 6:35 PM
 

Lauren,

 

As I understand it: there is no specific hormone that triggers cleavage after the zygote has formed - at least none that we have covered or that I can find online. Although, when the sperm enters the egg it does signal the egg to complete the second meiotic division (I don't think we cover this level of detail), so maybe that's what causes the delay?

 

 

Sarah

Picture of Lauren Brodehl
Re: Hormonal Influences to Fertilization
by Lauren Brodehl - Tuesday, 12 January 2021, 8:17 PM
 

I'm replying to myself here because upon reading the chapter again, I realized I misunderstood something! I was thinking the corpus luteum produced progesterone throughout the rest of the pregnancy to maintain endometrial thickness, but I read on page 339 that the placenta actually takes over secreting estrogen and progesterone at about 10 weeks when the corpus luteum no longer functions. Sorry for the possible confusion in my initial response! 

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Re: Hormonal Influences to Fertilization
by Candee Lam - Tuesday, 12 January 2021, 10:42 PM
 

I could not find the information for cleavage either and am hoping to discuss it collectively with Dr. Wilson at our next meeting but I was thinking of what controls mitosis?  When I looked into that, I found out it could be growth hormone and/ or CDK1.  Mitosis and its Stages in order: Prophase, Metaphase, Anaphase and  Telophase) - Jotscroll

Picture of Sarah Swager
Re: Hormonal Influences to Fertilization
by Sarah Swager - Tuesday, 12 January 2021, 6:24 PM
 

Howdy everyone,

 

As a side note: The first hormones that lead to cleavage and implantation are GNRH, LH, and FSH! It's important to not lose sight of where we begin.

 

Once the egg is released and the follicle turns into the CL, the CL begins making progesterone and some estrogen. Progesterone causes the decidualization reaction (which further prepares the endometrium for implantation) while the conceptus is going through cleavage. Without this progesterone implantation would likely not lead to a successful IUP, and the functional layer of the endometrium would sluff off.

 

Next, the blastocyst implants into the endometrium and the trophoblast cells begin making hCG => hCG keeps the CL alive until the placenta is able to make its own progesterone. No hCG=no CL=no progesterone=no live IUP.

 

It's hard to say that one hormone is more important than another because they are all required for a full term pregnancy; however, progesterone (really it's GNRH*) alone is the most important hormone for implantation to occur.

 

This video is from Crash Course! It's an excellent overview of pregnancy. (They have ton of videos on all sorts of topics.)

https://www.youtube.com/watch?v=BtsSbZ85yiQ

 

 

Sarah

Picture of Hailey Indelicato
Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 6:03 PM
 

Hi Sarah,

I love that you spaced everything out in your post, it made it really clear. You mentioned HCG, I'm going to throw you a scenario. We havent quite learned about normal HCG levels in each trimester but my CI was mentioning them to me today so I'm planning on doing some of my own research on it. Say we have a 10 week pregnancy and her HCG levels come back as 6,500mIU/mL. what do you think this could mean for the pregnancy? 

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 6:59 PM
 

Thank you for including the crash course video. Did you have any questions about this topic or first trimester that you didn't completely understand? I personally think I can go over differentiating the layers the mom and embryo contribute and what each role is. 

Picture of Hailey Indelicato
Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 7:31 PM
 

Please do Candee! I think I would benefit from hearing that again.

Picture of Nailah Hollman
Re: Hormonal Influences to Fertilization
by Nailah Hollman - Wednesday, 13 January 2021, 9:35 PM
 

Hello Ms. Sarah, 

 I really enjoyed your response, it was a nice clear and concise breakdown of development of the blastocyst and its key components. I like how you took the further step of not just hCG comes from but its impact on pregnancy on it one. Considering you discuss the blastocyst, I found a nice short video on the gastrulation process that initiates in the epiblast of the inner cell mass in the blastocyst. 

Here it is. I hope you find it helpful:

https://www.youtube.com/watch?v=BtsSbZ85yiQ

Picture of Ramandeep Singh
Re: Hormonal Influences to Fertilization
by Ramandeep Singh - Thursday, 14 January 2021, 10:20 PM
 

Hi Sarah,

I love CrashCourse and watched that video on pregnancy and fertilization to help me visualize everything well. I agree that progesterone is the most important for impanation to occur because without it we would not have a nice bed for the blastocyst. 

Picture of Lania Black
Re: Hormonal Influences to Fertilization
by Lania Black - Tuesday, 12 January 2021, 7:13 PM
 

Hormones play a HUGE role in a successful implantation and cleavage process. If even just one hormone isn't producing properly it could cause demise of the pregnancy as a whole. In my opinion all of the hormones are equally important and all have a domino affect on each other. For example, hCG which is a hormone that detects pregnancy, is produced by the placenta after implantation and supports the function of the corpus luteum, which then leads to the corpus luteum producing key hormones such as progesterone that is a major support to the baby's livelihood until the placenta takes over around 8-12 weeks. Therefore, as I mentioned each hormone plays a very important role in implantation and the cleavage process. Before taking this class, I honestly didn't realize all that went into the implantation process or the significance of these hormones. These hormones also are a help to us as sonographers when reviewing lab values. If we see an unusual lab value of any specific hormone that we know if detrimental to this process, it should automatically raise a red flag for us when performing our exam to be even more cognizant and thorough. Below I attached a link which a breakdown of six key hormones in pregnancy that was very helpful for me to read. Hopefully, you lovely ladies will appreciate it as well.

 

https://www.compoundchem.com/2019/02/28/pregnancy-hormones/

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Tuesday, 12 January 2021, 8:55 PM
 

Hi Lania! Hormones definitely work synchronously with each other and one couldn't function without the other. Did you find a way to remember the irregular lab values? I had trouble remembering what the lab values were but I know normal is 1800 mIU. I checked out your link and I really liked that they added hormones thats affect pregnancy after implantation like prolactin and oxytocin. 

Picture of Lania Black
Re: Hormonal Influences to Fertilization
by Lania Black - Thursday, 14 January 2021, 8:54 PM
 

Hi hun! I'm actually making a list of all the irregular lab values and regular lab values that I have observed while in clinical. I would be more than glad to share them with you!

Picture of Alexis Rojas
Re: Hormonal Influences to Fertilization
by Alexis Rojas - Wednesday, 13 January 2021, 8:43 PM
 

Hi Lania! Thanks for sharing that great visual! I haven't scanned any OB patients yet, but I know you have. In your experience, how often do the OB patients have recent lab work done in preparation for or as the reason for their exam? 

Picture of Lania Black
Re: Hormonal Influences to Fertilization
by Lania Black - Thursday, 14 January 2021, 8:57 PM
 

Hi Alexis! From what I've seen most of all the OB patients have prior labs that we can  take a peak at prior to the visit. It's been super helpful for me to take a look at these before starting the exam.

Picture of Allison Wine
Re: Hormonal Influences to Fertilization
by Allison Wine - Thursday, 14 January 2021, 7:37 PM
 

Lania,

 

Thanks for mentioning to look at labs and correlate them to out sonographic findings. I love the chart you added. I didn't know that estrogen did so much more than just thicken the lining of the uterus. Specifically how it helps to develop fetal organs. 

Picture of Zulema Hernandez
Re: Hormonal Influences to Fertilization
by Zulema Hernandez - Tuesday, 12 January 2021, 8:09 PM
 

I believe there isn’t necessarily one single hormone that is more important, because they all play an important role and work together to make implantation possible.  Starting in the hypothalamus, secretion of GnRH occurs, then the anterior pituitary gland releases LH and FSH, and the ovaries produce estrogen and progesterone. LH surge triggers ovulation. The Graafian follicle is now a corpus luteum and secretes progesterone which causes the endometrium to thicken and prepare for implantation. After implantation, hcG is released, which keeps the corpus luteum alive, allowing it to keep secreting progesterone to maintain the endometrium. hCg also plays an important role in determining if a woman if pregnant, because levels can be detected.


Here’s a short animation video of implantation of a blastocyst. It’s fascinating to know how each hormone plays a role in allowing this important process to occur!

https://www.youtube.com/watch?v=PAVo16b_6j4

I found this small chart to be a good summary!

hormones

Picture of Lauren Brodehl
Re: Hormonal Influences to Fertilization
by Lauren Brodehl - Tuesday, 12 January 2021, 9:24 PM
 

Hi, Zuly!

I'm happy that your video showed the differentiation between the morula and blastocyst because I was having a hard time with those and the visual helped!

One thing I found after my original post to this as well was that after the corpus luteum secretes progesterone for about 10 weeks, it eventually becomes non functional, and the placenta begins to take over its job of secreting progesterone and estrogen for the rest of the pregnancy! Its so interesting how they all work together and have specific jibs at specific times! I'm linking an image that I really liked to show hormone levels throughout a pregnancy to show how some peak and some (like progesterone) continue to elevate during those 40 weeks!

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Wednesday, 13 January 2021, 12:15 PM
 

Great chart Zuly! I was looking into hormones a little bit more and searching for good visuals when I encountered Human Placental Lactogen. We don't see it until after implantation as it is produced by the placenta, but it was interesting to learn about. hPL breaks down fats so the embryo can absorb the nutrients. Apparently it can also lead to carbohydrate intolerance and insulin resistance for the mother. Abnormal results of hPL can indicate an issue with placental function. I imagine we will learn more about this in future lectures.

Source: https://www.ucsfbenioffchildrens.org/tests/003915.html

Picture of Zulema Hernandez
Re: Hormonal Influences to Fertilization
by Zulema Hernandez - Wednesday, 13 January 2021, 9:18 PM
 

Hi Leah!

Fantastic research! I was not aware of Human Placental Lactogen. It seems like it plays a very important role in the nutrition of the embryo and health of the mother so I'm glad you brought it to our attention. I agree we will probably learn more about it soon, but it's amazing to know how many important roles the placenta plays! 

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 7:07 PM
 

Yay I'm happy to see everyone is adding charts and visuals. I like that you included the hormone that males produce. It is also so fascinating to think of the enormous amounts of hormones that are necessary for females to function and the minuscule amount that men need.  Have you noticed a big difference when you scan men in clinics vs women? I haven't got to scan many men pls share your experience!

Picture of Zulema Hernandez
Re: Hormonal Influences to Fertilization
by Zulema Hernandez - Wednesday, 13 January 2021, 9:39 PM
 

Hi Candee,

I've only scanned one male so far, an older gentleman. I scanned his bladder and prostate, although I wasn't 100% sure how to scan prostate, it was essentially like looking for a tiny uterus, and it sort of looked like one too, at least to me haha! It's definitely interesting to have that switch since we're used to scanning only each other.

Picture of Sarah Swager
Re: Hormonal Influences to Fertilization
by Sarah Swager - Wednesday, 13 January 2021, 7:19 PM
 

Zuly,

  I completely forgot it's GnRH and not GNRH. Haha. Thanks for the reminder!

 

 

Sarah

Picture of Nailah Hollman
Re: Hormonal Influences to Fertilization
by Nailah Hollman - Wednesday, 13 January 2021, 9:26 PM
 

Hi Ms. Zuly, 

I enjoyed your response. I also included each hormones played a significant role, they are all essentially pieces that make up a puzzle. Thank you for sharing that video ! It was nice quick visualization of implantation. I think I will continue to look at that group's video. The chart you posted made me think of how it takes so much energy and steps for the millions of sperm to reach one egg. However the outcome of a beautiful baby is truly worth the process. 

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Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Tuesday, 12 January 2021, 8:33 PM
 

Hormones play huge role in or daily lives so you can imagine how important they are when carrying another human being inside you. It all starts off with Gnrh, LH, and FSH, a surge of LH initiates ovulation. After the mature follicle ruptures, releasing the egg, it becomes the corpus luteum. This structure is really important because it secretes progesterone. Progesterone keeps the endometrium nice and thick for the blastocyst to attach to and survive. Trophoblasts produce HCG which plays a big role in pregnancy because it's main function is to keep the corpus luteum functioning and we're able to detect pregnancy with these levels. I liked this graph because it shows the hormone levels throughout the whole pregnancy and it's easy to follow.  I also saw some graphs with hPl (human Placental Lactogen) and I don't remember going over it. Does anyone know about it and what's the purpose? In my opinion, I don't think one hormone is more important over another, they are all needed for specific things and without one the others wouldn't perform the same.

Pin on MCAT

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Re: Hormonal Influences to Fertilization
by Brittany Lopes - Wednesday, 13 January 2021, 9:57 AM
 

Hi Hailey!

You bring up a good question about Human Placental Lactogen. To be honest, I had never heard of it until you mentioned it in your post! I was able to find a nice little description of what it is on the UCSF Benioff Children's Hospital website. Basically, it is a hormone secreted by the placenta and it helps to provide nutrients for the baby by breaking down fats from the mother.

I did a little more reading and found that this hormone is typically monitored through a blood test during pregnancy to ensure levels aren't too high or too low. A low level may be associated with choriocarcinoma and a high level can be associated with a molar pregnancy!

Here is the website in case you're interested in finding out what other conditions abnormal levels are associated with! I loved how this website was made for potential patients to gather information; this made it easy to read and broke it down simply.

https://www.ucsfbenioffchildrens.org/tests/003915.html#:~:text=Human%20placental%20lactogen%20(hPL)%20is,carbohydrate%20intolerance%20in%20the%20mother. 

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Re: Hormonal Influences to Fertilization
by Leah Borries - Wednesday, 13 January 2021, 12:28 PM
 

Ah great minds Hailey and Brittany! I was just posting about hPL in response to another post. I'm very interested to see if we encounter much with this hormone as sonographers, since I hadn't heard of it before either. According to the UCSF website, some of the differentials associated with abnormal hPL levels are choriocarcinoma, aborting hydatidform mole, trophoblastic pregnancy, and more. Would an abnormal hPL level lead a practitioner to order an ultrasound? 

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Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 5:51 PM
 

Hi Leah! thanks for looking into my question! this is me guessing but i feel like an ultrasound would be ordered for an abnormal hPL because the babies life is ultimately at stake in these situations and if it's not ordered and something is seriously wrong with the pregnancy, then its on the doctor who wasn't diligent enough. Better safe than sorry!!!

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Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 7:33 PM
 

Hello again! i just watched a video and it said the placenta also secretes RLN which is relaxin and it loosens joints and ligaments to increase flexibility for the mom!

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Re: Hormonal Influences to Fertilization
by Leah Borries - Thursday, 14 January 2021, 6:02 PM
 

Oooooh thats interesting! Good find Hailey!

[insert joke about -relaxin'- here]

Picture of Brittany Lopes
Re: Hormonal Influences to Fertilization
by Brittany Lopes - Thursday, 14 January 2021, 5:34 PM
 

Hi Leah!

Too funny how we both shared the same source for information on hPL! 

I agree with what Hailey said about how a practitioner would likely order an ultrasound exam if the hPL levels are abnormal because the pregnancy may be at risk. I feel like this would be a hormone typically monitored through blood tests throughout a pregnancy..? I've never had children myself though so I'm not completely sure! I look forward to learning more about it when we talk about the placenta more.

Picture of Hailey Indelicato
Re: Hormonal Influences to Fertilization
by Hailey Indelicato - Wednesday, 13 January 2021, 5:48 PM
 

Thanks so much Brittany! I'm going to do some more research as well, I wonder if the placenta produces anymore hormones that we don't know about yet, i'll look into it!

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Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 7:13 PM
 

Hm we haven't learned about human placental latrogen yet but would it be the same as human chorionic gonadotropin hormone?  I wonder if any other lab values are essential to check besides HCG. 

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Re: Hormonal Influences to Fertilization
by Alexis Rojas - Thursday, 14 January 2021, 8:06 PM
 

Hello again, friend! I read this article that Karen posted on the other DB. It talked about how low progesterone serum levels paired with elevated serum hCG, a thickened endometrium and no presence of a GS is a combination indicative of a failing pregnancy. I'm not sure if progesterone serum levels are monitored with a suspected pregnancy, but the article suggests that measuring it may be helpful when coming to a conclusion about whether or not to undergo a D&C. 

This also serves as further evidence that progesterone is not only important during implantation, but long after it is done to continue providing a nourishing environment for a pregnancy.

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Re: Hormonal Influences to Fertilization
by Lauren Brodehl - Thursday, 14 January 2021, 12:16 PM
 

Hi Hailey!

I'm so happy you talked about LH and FSH playing an important role because I'm pretty sure I skipped them and went straight to estrogen and progesterone in my response! Whoops! They are absolutely vital to the pregnancy as well, since without them, the follicle would never release an egg to be fertilized! 

I did some quick research on Human Placental Lactogen, and it looks like it starts to rise when HCG starts to plateau. It is related to mammary growth during pregnancy and milk production. Hopefully we will learn more about it down the road!

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Re: Hormonal Influences to Fertilization
by Monica De Ocampo - Tuesday, 12 January 2021, 10:28 PM
 

 

The hormones are a significant part during the implantation and cleavage process. Hormones are needed to stimulate and grow important parts of the uterus to set implantation. Once fertilization occurs, the sperm and egg become one—the zygote. This zygote performs cleavage, the rapid division of cells. As this is multiplying and developing, there is a rise of high level of hormones called estrogen. Estrogen would thicken the endometrium. The corpus luteum, would then produce the hormone, progesterone. Progesterone allows implantation to occur. If these two hormones were to decrease, menstruation would begin again. Although, if the hormones steadily increase, then we have a successful road to implantation.

About six days after fertilization, implantation would then occur. The syncytiotrophoblast begins to produce the hormone hCG. This hormone ultimately extends the life of the corpus luteum! As the corpus luteum also continuously produces progesterone to prevent the endometrium from shedding.

 

Personally, I do not believe any type of hormone is more important than another. They all spontaneously work together to build and create a healthy environment for life to grow. Below is a shared image that displays the stages of zygote to cleavage to implantation.

Sounds silly to ask... but if estrogen and progesterone must increase for pregnancy to occur, would pathology occur if there was more of estrogen than progesterone? Or vice versa? Or it wouldn't even affect this process?

 

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Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 7:21 PM
 

That is such a good question Monica. I like your thinking, but to answer your question I don't think there would be any pathology if there was a high spike just because our bodies are "programmed" to prepare for the surge of hormones every month. I do remember that if there are high levels of artifical estrogen (tamoxafin) then fibroids can occur. 

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Re: Hormonal Influences to Fertilization
by Alexis Rojas - Wednesday, 13 January 2021, 8:13 PM
 

Hi Monica! What an inquisitive question! I'm not an expert by any means and I tried to find studies related to your question with little success. Since I couldn't find any pertinent info, my guess would be that the levels of estrogen or progesterone relative to one another wouldn't an be a big issue. I think the levels of each of them individually would be of more concern. For example, if progesterone was abnormally low, decidualization of the endometrial tissue would not be adequate to support implantation regardless of the estrogen level. This would be a great question for Dr. Cole if we get to see her again!

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Re: Hormonal Influences to Fertilization
by Nailah Hollman - Wednesday, 13 January 2021, 9:14 PM
 

Hello Monica, 

 Great response. I like how you included low levels of estrogen and progesterone initiate the next menstrual cycle. It was thoughtful of you to include what could prevent implantation. What funny is part of your question about estrogen and progesterone came up in my search results while I was researching. When estrogen levels are substantially high compared to progesterone , it is a phenomenon known as estrogen dominance. This website list several effects of estrogen dominance: 

https://www.healthline.com/health/high-estrogen#symptoms-in-women

 

Further information I found stated there are not any known severe consequences to high progesterone. The site stated that high progesterone levels are associated with increased risk of breast cancer; and that high levels are a consequence of congenital renal hyperplasia. Information was provided by:

https://www.yourhormones.info/hormones/progesterone/

 

Picture of Allison Wine
Re: Hormonal Influences to Fertilization
by Allison Wine - Thursday, 14 January 2021, 7:32 PM
 

Hey Monica,

 

I love the visual and your question. In my opinion I believe anything is possible. However, I think a signification increase in estrogen or a prolonged increase in estrogen can increase a persons chances in regards to developing a pathology. We as women need estrogen not only for reproductive purposes but estrogen influences how we use calcium and bone health. It also helps to maintain proper levels of cholesterol. I did read online that it is very rare to get cancer while pregnant, and that when it does occur melanoma is the most common. It is also noted that since estrogen is linked to certain cancers and estrogen levels during pregnancy increase, drugs like tamoxifin are not given because they have shown to cause birth defects to the unborn fetus. 

 

Here is a link to the study! It is actually very interesting.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6396773/ 

 

 

 
 
Picture of Karen Chow
Re: Hormonal Influences to Fertilization
by Karen Chow - Thursday, 14 January 2021, 7:34 PM
 

Hi Monica,

I love the diagram you included! I agree that everything works together in order for the whole process of maintaining a pregnancy to work. That is an interesting question that you asked, I wonder if our moderators will find the answer? We all know it's never good to have TOO much of anything!

I will be keeping your diagram for studies! 

 

Thanks!

Karen

Picture of Lania Black
Re: Hormonal Influences to Fertilization
by Lania Black - Thursday, 14 January 2021, 9:03 PM
 

HI Monica! I love this visual and the question you posed! It made me super curious to find an answer! I looked it up and so far all I've seen is if there is increased estrogen than normal during pregnancy it can cause nausea. But when not pregnant, it looks like too much estrogen could cause a number of issues.

  • bloating.
  • swelling and tenderness in your breasts.
  • fibrocystic lumps in your breasts.
  • decreased sex drive.
  • irregular menstrual periods.
  • increased symptoms of premenstrual syndrome (PMS)
  • mood swings.
  • headaches.

 

Picture of Monica De Ocampo
Re: Hormonal Influences to Fertilization
by Monica De Ocampo - Friday, 15 January 2021, 8:21 PM
 

Thanks so much for looking up my questionable symptoms! Its really interesting to find how the body works and what kind of questions to ask the patients, to look out for anything else that may be questionable 

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Re: Hormonal Influences to Fertilization
by Alexis Rojas - Wednesday, 13 January 2021, 7:00 PM
 

The cleavage process lasts from the first division of the zygote and ends when the conceptus becomes a blastocyst. This corresponds to day 1 to day 5 or 6 following fertilization. Once the blastocyst is hatched from the zona pellucida, the implantation process can begin. 

 

According to the image below, during the 5-6 days following ovulation estradiol levels drop then rise again. Additionally, the progesterone levels begin rising significantly around 1-2 days after ovulation. During the implantation window (starting ~ 6 days after), the progesterone level is rising to its peak. Perhaps during the first 1-2 days it takes for progesterone levels to take off, estradiol plays a role in continuing to grow the endometrium to give a solid foundation for decidualization to build on top. 

 

Progesterone is responsible for driving the decidualization reaction in the endometrium. Decidualization makes a number of changes in the morphology of the tissue to make it more receptive to implantation.  Therefore, in order for implantation to be successful, progesterone levels have to stay elevated. If the progesterone levels drop prior to implantation, the spiral arteries of the functional endometrium will start to constrict. The endometrium will no longer be in a state to accept the blastocyst and allow it to thrive. 

 

Once the implantation process begins, hCG is secreted by trophoblasts of the blastocyst. hCG’s job is to keep the corpus luteum from regressing in order to maintain the elevated progesterone levels until the placenta can take over toward the end of the first trimester. 

 

If we are thinking only about what the hormones do specifically in the cleavage and implantation processes, I would consider progesterone to  be more important because without decidualized tissue, a pregnancy would likely not be feasible. However, thinking about the bigger picture of the entire cycle, estradiol plays a larger role. Without the rise in estradiol levels, there would be less endometrial thickening, no LH surge, no ovulation, no corpus luteum, and no chance for fertilization. 

Image credit: https://courses.lumenlearning.com/wm-biology2/chapter/the-ovarian-cycle-the-menstrual-cycle-and-menopause/

 

Image source: https://media.springernature.com/original/springer-static/image/chp%3A10.1007%2F978-4-431-55972-6_2/MediaObjects/332562_1_En_2_Fig2_HTML.gif

Picture of Candee Lam
Re: Hormonal Influences to Fertilization
by Candee Lam - Wednesday, 13 January 2021, 7:24 PM
 

Thank you for sharing the great visuals. Your answer is always so concise. Can you relate any of the information to what you have seen in clinicals?

 

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Re: Hormonal Influences to Fertilization
by Alexis Rojas - Wednesday, 13 January 2021, 8:36 PM
 

I like that question! I haven't seen any patients with endometrial cysts or suspected early pregnancy (or any pregnant patient) so I haven't been able to apply my new OB knowledge. Hopefully soon though!

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Re: Hormonal Influences to Fertilization
by Chrishawna Porter - Thursday, 14 January 2021, 3:49 PM
 

Hi Alexis,

The amount of detail you included in your response is amazing and also a great refresher of some parts of the menstrual cycle we covered during gynecology. I noticed you mentioned Estradiol specifically which I had forgotten was the primary type of estrogen formed in the female body. This got me thinking about where the other two types of estrogen fit and if we would encounter them during pregnancy. Estrone seems to be the weakest of three and is the only remaining form of estrogen in PM women. One other little fun fact is that it is not just developed in the ovaries but also from the adrenal glands and adipose tissue. The third type, Estriol is made from the placenta and will only be found during pregnancy! Here is a cool graphic on the types of estrogen made both in and outside the body:

Picture of Nailah Hollman
Re: Hormonal Influences to Fertilization
by Nailah Hollman - Wednesday, 13 January 2021, 8:50 PM
 

There are a few hormones that play a significant role in the implantation and cleavage process. In order for implantation to occur, there needs to be an egg to implant. Ovulation, releasing of an ovum from a mature follicle, is trigger by luteinizing hormone (LH). The mature follicle the egg was released from, transforms into the corpus luteum. The corpus luteum secretes progesterone, which thickens the lining of the uterus and prepares it for implantation. Furthermore in order for cleavage to occur, a zygote must be present to divide. In other words, a sperm needs to have successfully fused membranes with the ovum. According to Khan Academy, estrogen plays a key role in assisting the sperm to pass through the vagina and cervix to reach the uterus to create a zygote. Estrogen secretes glycogen that is metabolized to make the vagina acidic. Low pH levels discourage the growth of pathogens, which can prevent sperm cells from reaching the ovum. Semen, the fluid that contains sperm, has basic properties that allow it to thrive in the acidic conditons. Furthermore estrogen thins the cervical mucus, providing for a smoother transport of sperm (khanacademy.org). However once fertilization occurs, a mucus plug seals the cervix, which creates a barrier that protect the fetus from infection. Lastly the syncytiotrophoblast cells of the blastocyst secrete hCG, indicating pregnancy.

         In my opinion, all the hormones are equal because they each play a role to contribute to development of fetus.

 

https://www.khanacademy.org/test-prep/mcat/cells/embryology/a/egg-meets-sperm

Picture of Monica De Ocampo
Re: Hormonal Influences to Fertilization
by Monica De Ocampo - Wednesday, 13 January 2021, 10:49 PM
 

Hello and sweet dreams Nailah!!

This topic was a great refresher, back from GYN menstruation hormones cycle! I could never NOT forget about Chrishawna's ovulation drawing. We will memorize many new drawings this quarter!! #TeamVisualLearners.

I concur. Hormones are weaved in and supported all together. If one hormone fails, it would be a whole domino effect, and potentially not be recognizable to even house a zygote 

Thank you for also contributing a great resource to your response. Its convenient that this website also shares images, relaying step by step of embryology!!

 

Picture of Molly McCain
Re: Hormonal Influences to Fertilization
by Molly McCain - Thursday, 14 January 2021, 9:56 PM
 

Hi Nailiah!

I love your post and think its important to break down every step as you did in order to fully understand. You explained everything so well! I also enjoy using khan academy as a resource. It's fascinating how a mucus plug seals the cervix in prevention of infection. That's great info to know. 

Thank you!

Picture of Molly McCain
Re: Hormonal Influences to Fertilization
by Molly McCain - Thursday, 14 January 2021, 12:22 AM
 

All hormones in implantation and the cleavage process play a huge role in a woman's reproductive journey. GnRH is secreted by the hypothalamus and stimulates FSH and LH from the anterior pituitary gland. FSH is responsible for promoting follicle development within the ovary leading to an egg being produced. Estrogen appears around the egg which is needed in order for a pregnancy to be supported. Estrogen stimulates the endometrium to thicken before ovulation occurs. There is then a surge in LH which triggers ovulation. LH is responsible for the maturation of a graafian follicle, which contains the matured ovum. The follicle then becomes the corpus luteum, which produces estrogen and large amounts of progesterone. Progesterone causes the endometrium to become thickened (decidualization occurs) and prepared for a blastocyst to implant successfully. Once implantation begins, trophoblasts produce HCG which plays an important role in maintaining the corpus luteum. Without the HCG being maintained, the pregnancy would not be able to continue on because the blastocyst would not be well supported. HCG needs to remain maintained until the placenta later on within the first trimester takes over the process of maintaining progesterone.

It seems as if all of the hormones play such a crucial role in the development and maintenance of a fetus especially estrogen and progesterone. Without estrogen, we wouldn’t have the endometrial thickening prior to ovulation occurring, an LH surge would not take place, which would lead to the absence of a graafian follicle being matured, and finally the corpus luteum wouldn’t be there to maintain a pregnancy. For progesterone, if we didn’t have it around then we wouldn’t have decidualization reaction to occur and implantation would not be possible.

 

I also wanted to share this vide on Khan academy which makes embryogenesis a bit easier to digest. I like the visuals within it: 


Early embryogenesis - Cleavage, blastulation, gastrulation, and neurulation (video) | Khan Academy

Picture of Leah Borries
Re: Hormonal Influences to Fertilization
by Leah Borries - Thursday, 14 January 2021, 6:06 PM
 

Molly that is such a great video, I'm glad you shared it! I watched it a few times last week to really help me understand cleavage and implantation. As a visual learner, I really appreciated the step by step illustrations and food analogies. I will never not think of the mulberry and how it is literally latin for "morula".

Picture of Molly McCain
Re: Hormonal Influences to Fertilization
by Molly McCain - Thursday, 14 January 2021, 10:12 PM
 

Hey Leah!

That's awesome you also watched the video last week and found it helpful! I love how he draws out each step and explains each into depth. I really appreciate the break down too since there's a lot for us to retain. I won't forget that morula means mulberry either! Anything visual to make things stick is great! 

Picture of Karen Chow
Re: Hormonal Influences to Fertilization
by Karen Chow - Thursday, 14 January 2021, 7:30 PM
 

While I want to say that progesterone is the most important because it prepares the uterus for implantation (decidualization) and without it, a pregnancy would not occur, one must also keep in mind the other hormones that got the zygote to the point of implantation in the first place. Without LH, there would have been no egg released to fertilize and then go through the cleavage process. Without hCG to sustain the corpus luteum there would be a shortage of progesterone. The female body is a well orchestrated chaos of hormones that work in tandem to ensure that everything functions the way it should.

Here is a diagram that I think is really helpful! Kinda huge, sorry.

Picture of Monica De Ocampo
Re: Hormonal Influences to Fertilization
by Monica De Ocampo - Thursday, 14 January 2021, 9:55 PM
 

Hi Karen!

I struggled so much trying to list all the hormones that occur during the implantation and cleavage. This image that you shared attached reviews the menstrual, fertilization, and menopause cycle so well! How they all work together, confuses me. I'm just aways questioning if one comes up, or comes down, so much can happen. 

I'm just trying to keep my mind straight ahead and not try to confuse or mix up anything else together. 

Thank you for sharing (-:

Picture of Ramandeep Singh
Re: Hormonal Influences to Fertilization
by Ramandeep Singh - Thursday, 14 January 2021, 10:10 PM
 

Hello Karen,

I really like your diagram, it really depicts the different roles that each hormone plays nicely. I too agree with you that every hormone in a female's body is equally as important because they work in a tandem so if one fails it would mean a domino effect. I like how you mentioned the LH surge that causes ovulation because you're right without an egg to fertilize we would not even be thinking about implantation. 

Picture of Ramandeep Singh
Re: Hormonal Influences to Fertilization
by Ramandeep Singh - Thursday, 14 January 2021, 10:06 PM
 

Hormones play a key role during the implantation process. Without the corpus luteum secreting progesterone and estrogen then we would  not have nice thick bed for the blastocyst to implant itself into it. Also, hCG comes in to maintain the corpus luteum so that these hormones can continue to be secreted. Therefore, I think that all the hormones are equally as important because the have to work together as a team.

The trends of HCG, estrogen and progesterone during pregnancy. The... |  Download Scientific Diagram

Picture of Nailah Hollman
Re: Hormonal Influences to Fertilization
by Nailah Hollman - Friday, 15 January 2021, 7:46 PM
 

As I was going through the discussion board and I was looking at videos I see variations in the amount of cells that make up the morula. Is it 16 or 32? Or is it a range from 16-32?

Picture of Chrishawna Porter
Re: Hormonal Influences to Fertilization
by Chrishawna Porter - Saturday, 16 January 2021, 9:35 AM
 

Hi Nailah!

I remember during Alexis's awesome presentation either Paris or Dr. Wilson mentioned that it can be anywhere from 8-32 cells! In many of the different sources I viewed, 16 was the most common number for the morula, but I think as long as its in the 8-32 cell range it can be a morula!