Hormone Control - Why Hormones Have Everything to Do With Making a Baby

Tonight will be the first night of injections, the first night of our journey toward making a miracle. What will I be injecting? A hormone called follicle-stimulating hormone (FSH). Lots and lots of FSH.

I really wanted to do a post about hormones, because hormones play such a huge role in all of this. The only way to really appreciate the in vitro process is to understand the hormones involved in making a baby. It’s interesting how each hormone has its specific job, but more than that, I find it so fascinating that the hormones communicate with each other, and take their cues from each other on when they need to be active and when they need to slow down. It blows my mind.

If you'd rather see me explain about hormones on a video, then you can click on this link to watch the youtube video I made on the topic. Otherwise, read on!

We’ll be talking about four main hormones:

(1) Follicle-stimulating hormone (FSH) fuels the growth of the eggs. Remember that the eggs live inside sacs called follicles and the egg and follicle need to grow and mature before they can be released and ovulate. It’s the FSH that fuels that growth.

(2) Luteinizing hormone (LH) has the specific job of triggering the egg to release from the follicle and out of the ovary. In other words, LH is what triggers ovulation.

(3) Estrogen is in charge of building up the lining of the uterus.

(4) Progesterone helps the lining of the uterus to get all the nutrients and enzymes it needs to be a healthy and welcoming place for the embryo.

At the start of a cycle, when a woman is on her period, her estrogen and progesterone levels are very low. That sends a cue to the FSH, essentially saying, “We have no baby on board. So we need to start making another egg.” So the FSH kicks in and starts nourishing those eggs. They grow, mature, and get ready to ovulate. This process of growing and maturing usually lasts about two weeks, and makes up the first half of the cycle.

Interestingly enough, the growing eggs produce estrogen! As they grow and grow, the estrogen levels get higher and higher, and the lining of the uterus gets built up. So the growing egg is essentially in charge of building its own home, which is pretty cool. By the time it ovulates, the lining should be in pretty good shape for accepting that embryo.

So how does ovulation occur? Well, as the estrogen levels get higher and higher, they eventually reach a point that cues the luteinizing hormone (LH) to do its job. The LH recognizes the high estrogen levels and says, “Wow, we’ve got an egg that’s ready to roll! Time to open the gates!” The LH kicks in and, about two weeks into the cycle, helps the follicle to release its egg. So, not only does the egg build its own uterine lining with the estrogen, but it also uses the estrogen as a keycard to get itself outta there! Crazy, huh?

And after all that hard work, that precious little egg has only 24 hours to be fertilized. That’s right, twenty-four hours! We are all here because everything was at just the right place at just the right time. If only the rest of our lives were so serendipitous!

Now remember that the progesterone is needed to get that uterine lining really rich in nutrients. It’s pretty important in helping to make a friendly environment for the embryo, which is why it’s called progesterone, meaning pro-gestation. So where does the progesterone come from? Are you ready? Because this is fascinating! After the follicle releases its egg, it turns into a different structure, called a corpus luteum. Now that it’s released its egg, it has a whole other job to do – get that uterine lining super healthy and friendly for that egg! So this follicle, now the corpus luteum, actually stays on board and starts producing progesterone! Basically, the follicle is responsible for a whole lot and is an amazing structure! It helps incubate and mature the egg, helps release the egg, and helps build up and enrich the uterine lining. High five, follicles. Five gold stars for you.

So, the egg is floating around hoping to get fertilized. When it meets up with the sperm and becomes an embryo, then it’ll find its way down to the uterus and implant. This can actually take about a week, so you usually have an embryo implant about three weeks into your cycle, or a few days before you’d have your period.

As the embryo nestles in and gets comfy, the cells around the embryo are having a big ol’ party that their guest of honor has arrived. Those cells produce a hormone called HCG, which probably sounds familiar! That’s the hormone we measure when we are checking if a woman is pregnant because those cells are whooping and hollering and letting us know that there’s a baby in there!

But the HCG does more than let us know we’re pregnant. The HCG also sends a signal to the corpus luteum, saying, “We do indeed have an embryo here so we need to keep this uterine lining up and running and in tip top shape. You’re gonna need to stay on board and keeping sending us progesterone until we can get a little more self-sufficient around here.” So the HCG and the corpus luteum communicate with one another, with the HCG requesting more progesterone from the corpus luteum to keep the embryo nourished.

So we’ll see the HCG levels rise and the progesterone up at a healthy level as we progress through a pregnancy.

Now, if there was no fertilization, no embryo, and no implantation, then about two weeks after releasing its egg, that corpus luteum will turn in its notice and retire. Without a baby to support, there’s no longer a need for that progesterone so the corpus luteum is officially done with its job. As a result, progesterone and estrogen levels will go down, farther and farther. Without the support of those hormones, the uterine lining will break down and shed. Ta da, here comes your period.

And what else happens? Oh yeah, that FSH wakes back up because the progesterone and estrogen levels are low again. Time to get going and build up another egg! And the cycle continues.

Isn’t it all amazing how all the hormones communicate together? So much work all in an effort to make a baby each month.

What will we be doing differently for me with in vitro? First of all, I have been on birth control over this last month because they don’t want any kind of activity happening in my ovaries. With birth control, you’re giving yourself progesterone and estrogen hormones. With those hormones elevated, your body thinks you’re pregnant. So your FSH never kicks in, you don’t grow any eggs, and you don’t ovulate. This is what we wanted, for my ovaries to be inactive and quiet before we get started.

On Friday, September 18^th, I went in for an ultrasound, or a “suppression check.” They wanted to make sure that my ovaries looked like they were inactive and I had no growing follicles in there, that everything was indeed suppressed from my birth control. Everything checked out okay and they were able to count my follicles. I had 18 on my right ovary and 8 on my left, so 26 follicles overall!

If you want to see the video of my ultrasound, click here.

Normally, my body would produce enough FSH so that one egg would end up becoming the dominant egg, or dominant follicle, and would be the one to be ovulated in hopes of fertilization. And that’s a good thing. Our bodies are meant to carry one baby and it would be a disaster if we were dropping twenty eggs every month!

But, with in vitro fertilization, we are going to be dousing all those follicles with a big ol’ dose of FSH, because we want as many eggs as possible for a chance at fertilization. I will be giving myself 300 units of FSH each night for the next week and a half or so, clapping and cheering for all those eggs to grow and mature! 

When I did in vitro a few years ago, I was giving myself a daily dose of 450 units. But current research shows there's not much of a benefit once you go past 250 or 300. Basically, my ovaries are pretty saturated at that point. Not only that, but too much FSH can create a higher risk of hyper-stimulation and may cause a loss of egg quality. So we're shooting for the lower dose at 300 units, which I'm hoping will produce better eggs. Not only that, but it's better for my wallet anyway. My FSH medications cost $45 for every 75 units, so I just saved myself $90 a day by bumping things down.

As you can imagine, all those follicles will be producing quite a lot of estrogen. Remember that high levels of estrogen lead to ovulation and we don’t want that. We don’t want all these precious eggs to get released! So, about five or six days into this process, I will be taking a medication to suppress the luteinizing hormone and make sure those eggs don’t release prematurely. Not until we are ready to get them out ourselves!

Just like any other pregnancy, it’s going to be important for my progesterone levels to be high and my uterine lining to be nutrient-rich. So, once we are about to put those embryos in, I will start doing progesterone injections to make sure everything is as healthy as can be. Frankly, this is the worst part of the whole process because I have to do it every day for six weeks, it hurts and gets more and more sore, and I do the injections into my butt. Don’t worry, there will be no video blogs for the progesterone shots.

That’s it, folks! Now you know all about hormones, how they communicate, and the jobs they have to do. And now you know what I will be doing over these next few weeks – lots and lots of shots! All in our effort to make another miracle. I hope you learned something and I hope you feel more and more wonder at how amazing your body is!

By the way, I did a video of our first injection but it was kind of a learning process so I won't post it. Once we have it down, I will let you in on my world of mixing potions... I mean, hormones.