Follicles and fertility – what really matters, and what should we know?

How many follicles are good for fertility? (& more FAQs answered)

When trying to conceive, you’ll often hear about follicles – but what exactly are they, and how do they help your doctor understand and optimize your fertility?

Whether you’re planning for the future or in the middle of treatment, understanding follicle development can help you take charge of your journey.

To answer your most-searched questions, we went live with Dr. Deborah Ikhena-Abel (Dr. Debo) from Aspire Fertility Austin, part of The Prelude Network.

Watch as we cover:

• What follicles are and why they matter for fertility
• How follicle count relates to fertility potential
• The role of follicles in natural conception, IUI, and IVF
• How fertility clinics track and measure follicle development
• The ideal follicle size for conception
• Whether IVF affects follicle development or egg quality
• Ways to optimize follicle health, including medications, lifestyle, and supplements

Got questions about your fertility, or anything we covered with Dr. Debo? Connect with the Aspire Fertility team – or find your nearest Prelude Network fertility clinic here – to get answers, and explore your options.

Transcript

Eloise Edington

Everyone, and welcome back to those who just joined. I am about to go live with Dr. Deborah Ikhena-Abel, who is MD at Aspire Fertility Austin, Texas—a Prelude Network clinic—and we will be discussing everything there is to know about follicles and fertility.

So welcome back if you just joined. This is a conversation not to miss. Make sure you watch until the end, because we have some fantastically insightful questions for Dr. Debo to answer today.

Please also, if you have your own questions, feel free to ask live. I believe she’s just joined.

Hello Dr. Debo. Hello. Can you hear me okay?

Yes, perfect. How are you?

Dr. Deborah Ikhena-Abel

I am doing well. I’m sorry we had so many technical difficulties.

Eloise Edington

Not at all. We’re here now, so that’s perfect. I would love for you to please introduce yourself and tell us a bit about you and what you specialize in.

Dr. Deborah Ikhena-Abel

Yes, thank you for having me. My name is Dr. Deborah Ikhena-Abel. I go by Dr. Debo as well, and I am a fertility doctor—also known as the reproductive endocrinology and infertility specialist—and I practice with Aspire Fertility in Austin, Texas.

Eloise Edington

Wonderful. Today we’re going to dig right into follicles and fertility: what really matters, what people should know, what people ask you as an expert in the field.

So for people who are kind of new to fertility, perhaps seeking treatment or beginning stages, how would you explain what follicles are and why they are so important to your fertility journey? And how does that follicle count relate to overall fertility potential?

Dr. Deborah Ikhena-Abel

Yeah, so whenever I explain fertility to my patients, I like to use the analogy of the ovary on ultrasound.

It looks like a gray chocolate chip cookie with a bunch of black chocolate chips, and each chocolate chip is a follicle.

Each follicle has one microscopic egg inside of it, and the number of follicles on your ovaries tells us how many eggs you have available for that particular month.

Now in a given cycle, where you’re just kind of taking medications—or not taking any medications, you’re just going through the cycle on your own—your body will choose one of those follicles to ovulate, so release an egg from, at ovulation. At the end of that month, all of those follicles die away along with the egg inside of them.

So your follicle count is a measure of your fertility, of your egg reserve—specifically, the number of eggs you have available. Your follicles are the egg houses for the eggs that you have available for that particular month.

Eloise Edington

And could someone have a different follicle count from one month to another?

Dr. Deborah Ikhena-Abel

For sure. You can have some variation. It shouldn’t be a dramatic variation, so you wouldn’t go from having four follicles to having 13 follicles the following month.

But you may have 11 follicles one month and then have 13 the next month and then have 12 the next month, because there is some fluctuation. But it should fluctuate around a median, which is your normal.

Now over time, that number goes down. So if you have a follicle count of maybe 13 this year, and you go back in a couple of years to be evaluated, that number may be down to 10 or 9, because we expect that—just as your egg count decreases over time—your number of follicles, which is a reflection of your egg count, will decrease over time as well.

Eloise Edington

Makes complete sense. And could you have different numbers of follicles on each ovary?

Dr. Deborah Ikhena-Abel

For sure, yes. Our bodies are not perfectly symmetric, so you will have one side in most cases that has more eggs than the other side. Sometimes that can go back and forth as well.

Eloise Edington 

Makes sense. And how many eggs are contained within a single follicle, and could you retrieve follicles and find that there are no eggs inside them?

Dr. Deborah Ikhena-Abel

Yeah. So typically, we expect each follicle to have one egg inside of it. When we do an egg retrieval, we expect that about 80 to 90% of the follicles will have an egg inside of them, because some follicles will not have an egg inside of them.

Now as we get older, or if we have a very low egg count, the likelihood of having empty follicles does increase. That’s something that we may see in some patient populations more than in others.

But I’d say overall, when you do an egg retrieval, we expect about 90% of those follicles to have an egg inside of them.

Eloise Edington

So when people are coming to you and they’re during the stimulation process and you’re scanning them, does that give you a good indication of how many eggs you might get from a cycle as you get nearer to retrieval?

Dr. Deborah Ikhena-Abel

Yes, for sure. So even when I do the first ultrasound and I do the antral follicle count and I find out what the total number of follicles available is, that gives me a sense of what I would expect down the line in a future IVF cycle.

As we go through the IVF cycle and we follow the follicles over time, we also look at the size of the follicles. By the time you get to the trigger, any follicle that is about 13 millimeters or more is in the running for having an egg present at the time of retrieval.

Eloise Edginton 

That actually takes me on to one of my other questions, which is—obviously your specialty is judging when to trigger someone, because you want the follicles to be that optimal size—so what’s the parameters between sizes from the smaller size to the largest size you really want to push it to?

Dr. Deborah Ikhena-Abel

Yeah. So typically, when we decide when to trigger, we’re going based on the size of the largest follicles.

I typically like to have a couple that are about 20, so somewhere between 18 to 22, because our bodies are flexible. So it might not be exactly 20—it might be 21 or 19.

But then I also look at the size of all of the follicles.

So for example, if someone has a total of 10 follicles that are in the running and they have one that is 22, but all the rest are under 15, I’m probably going to keep going a little bit longer so that I have more follicles that are closer to 20.

But overall, in most cases, if you have a couple that are around 20 mm or so and the rest of the follicles are following closely behind, then that would be usually a good time to trigger.

Eloise Edington 

Does that make a difference then in terms of your stimulation and when you might trigger someone based on their age as well?

Dr. Deborah Ikhena-Abel

Yeah, so the age can definitely be a factor. We would look at the age combined with their estrogen level, for example, their progesterone level as they go through the cycle, and also if we have any historic data from a prior cycle.

For example, if there’s someone who in the past has ovulated earlier than anticipated, then that may factor in.

And then in some patients who are on additional medication—so sometimes you have patients who may be going through an IVF cycle or egg-freezing cycle because of a history of, let’s say, breast cancer, and they’re on a medicine called Letrozole to keep their estrogen levels low as they go through the cycle.

Now, studies show that in those patients, you do want to push them a little bit further so you have better maturity. So in that case, I may push to like maybe more like a 22-size follicle versus 20—again, just considering all the factors that are at play with that particular patient.

Eloise Edington

Yeah, that makes complete sense. And are there factors that influence this process in terms of whether a follicle would have an egg inside it? Is that in someone’s control?

Dr. Deborah Ikhena-Abel

You know, I would say probably not. Usually, the follicle either has an egg inside of it or doesn’t. A lot of the time, you’re not able to necessarily do anything differently to influence whether or not your follicle will have an egg inside of it.

I will say that for the most part, we expect that most of the follicles will have an egg inside of them, and a lot of the time, all of the follicles will have an egg inside of them.

But again, like I said, in certain situations where either you have a low egg count or when we’re older, you start to see that there might be more empty follicles. But it’s one of those things that, unfortunately, you’re not able to control what your follicles do with regards to the cycle.

Eloise Edington

Absolutely. Absolutely. We’ve had a couple of questions: if the largest follicle ovulates, will all follicles ovulate at the same time?

Dr. Deborah Ikhena-Abel

So it depends on the size of the other follicles. If the largest follicle ovulates and the other follicles are very small, then they’re not going to, because they’re not ready to ovulate, and they cannot really even receive the signals to tell them to ovulate.

But if the largest follicle ovulates and the other follicles are also close behind, then very likely they’re all going to ovulate at the same time. So it really depends on the size.

There are some cases where your doctor may say, “I’m going to trigger this large follicle, but we’re going to keep going for the rest of the follicles,” and that’s because those other follicles are so small that they’re not going to ovulate at the same time.

Eloise Edington

Yeah, absolutely. Thank you for that. And do you use an antagonist to stop ovulation?

Dr. Deborah Ikhena-Abel

Yeah, so that is one of the ways that we prevent ovulation during the cycle, because when you’re going through an IVF cycle, what you’re trying to do is delay ovulation until you have the right cohort and the optimal cohort of eggs for that cycle.

And so typically, we will use an antagonist to do that. This is administered as an injection that the patient will take, and it basically works by preventing your brain from releasing the hormone called LH, which is a hormone that triggers ovulation.

Now, there are other ways your doctor might do this. Another option would be to take a medicine called Lupron, which is an agonist, but it basically does the same thing. And also, there’s recent data showing that also giving progesterone at a particular dose can also prevent ovulation as well while going through an IVF cycle.

Eloise Edington

Interesting. Do you have patients—I was one of these patients—who panicked a little bit that I didn’t have the amount of follicles I wanted at the beginning of a cycle, and then ended up actually being pleasantly surprised by the number of follicles that were retrieved, having worried the whole way through stimulation that there weren’t going to be the number of eggs that I wanted?

Dr. Deborah Ikhena-Abel

Yes, this happens all the time, and I try to tell patients, when we start the cycle, most of your follicles are going to be small, and that’s okay.

Patients worry, like, “Oh, there are only two follicles that are greater than 10.” I’m like, “Well, you’re on the fifth day of your cycle, so of course most of the follicles are small.”

And then as you go through the cycle, the follicles will start to grow in size. It’s almost like you’re watching a flower bloom.

So you start off and there are a few petals, and then as you go through, more and more petals start to show themselves, and so more and more follicles start to respond—especially if we were expecting that to be the case.

So if you come into the cycle, you have a good count, and we’ve already discussed that we are expecting a pretty good outcome, most of the time it’s just a matter of being patient and trusting the process.

Eloise Edington

Absolutely. I think that’s really good advice. And onto that, how do you and Aspire Fertility clinic track and measure follicle development?

Dr. Deborah Ikhena-Abel

Yeah, so as you go through the cycle, whether it’s an IVF cycle or egg freezing cycle, you will be coming in for monitoring visits every couple of days. We track the growth of the follicles by doing transvaginal ultrasounds at these appointments.

We also check hormone levels. So we check an estrogen level because usually these follicles contain an egg each, and those eggs will make estrogen. So by tracking the estrogen levels, you’re able to tell what’s going on within the follicle for the most part.

We also check a progesterone level, because that gives us a sense of if, for whatever reason, you were to ovulate prematurely, then that would cause a pretty significant spike in your progesterone.

So that can be an indicator as well. But really, we’re monitoring you very closely with these frequent ultrasounds and blood tests as you go through the cycle to monitor how your follicles are responding, how your ovaries are responding.

Eloise Edington

So a combination of blood and also ultrasound?

Dr. Deborah Ikhena-Abel

Transvaginal ultrasound, exactly. 

And we mentioned it, but if you were to pick the ideal follicle size for conception, whether it’s naturally, IUI, or IVF, would that be a size that you could say somewhere around 20 is a good place to be?

So, plus or minus a couple of millimeters—keeping in mind that by 20, I mean 20 millimeters—these are very small increments. But 20 is a good average to look out for.

Eloise Edington

Okay, okay. That’s good to know. And this is a good question—can undergoing IVF treatment negatively impact follicle development and/or egg quality?

Dr. Deborah Ikhena-Abel 

Yeah, so as far as we know, this is not the case.

So whatever eggs we get during the cycle are the eggs that were there to begin with. We’re not able to necessarily change.

I’m going to assume you mean like, “Can going through an IVF cycle this month affect follicle development the next month?” I’m going to assume that’s what you’re asking.

Eloise Edington

Exactly. 

Dr. Deborah Ikhena-Abel

Okay, exactly, just making sure I’m answering the right question.

So basically, whatever we do with these follicles is not able to impact the next set of follicles, because those follicles that we have access to—we know if we didn’t retrieve them—they would just die at the end of that one.

We don’t currently have the technology to access future eggs for future cycles, which is part of why, if you have a low egg count, we are kind of tied to whatever your ovaries can give us in that particular month.

So if you go through an IVF cycle, you don’t have to worry that it’s going to affect next year’s eggs or next month’s eggs, because each month has its own group of eggs for that month.

Eloise Edington

Do you see differences—because I’ve heard this from someone before and I’d be interested to know whether you’ve seen this—like patients responding differently depending on the season?

Dr. Deborah Ikhena-Abel

Huh, I have not seen that. I haven’t seen the full season of the year, like winter versus summer. I haven’t seen that.

What I have seen—and there is data to support this as well—is that when patients cycle kind of back to back, we do see a better response in the subsequent cycle.

Eloise Edington

Interesting.

Dr. Deborah Ikhena-Abel

And the thought is that the first cycle almost kind of primes the ovary.

It’s almost like the ovary has done it once and now it knows how to do it again. So sometimes, even when you keep the protocol exactly the same, but you do a cycle right after the first cycle, you see a slightly better response overall.

Of course, there are exceptions to every rule, but overall you see a better response in that second cycle.

Eloise Edington

That’s fascinating. That first cycle—that was actually a question that just came through: what are your thoughts on back-to-back cycles?

Dr. Deborah Ikhena-Abel

Yeah, and then we typically see this benefit lasts for about three months after the previous cycle. So it doesn’t have to be like you go right into the cycle. It does last for a period of time afterward.

Eloise Edington

What would be patients’ reasons for doing back-to-back cycles?

Dr. Deborah Ikhena-Abel

Yeah, so if patients, for example, are trying to maybe bank embryos for a particular family size—so they are like, “I want to have three kids”—then that might guide us to do back-to-back cycles.

If someone has a genetic condition that they’re tested for in both of their partners, where there is a high chance that they may need more embryos—because you’re losing more embryos when you’re doing genetic testing plus testing for whether or not it’s a normal embryo—so that might be a reason to do back-to-back cycles.

The most common reason is patients with a low egg count. So patients who have a low egg count or who are older, we just know that overall outcomes tend to be poorer.

And so the more cycles you can do, the more likely you are to get the number of embryos you need to move forward with building your family.

Eloise Edington 

Yeah, that’s really, really useful to know. This is also a great question—actually something I was about to ask you.

Lifestyle changes, supplements, nutrition, exercise—is there anything that people can proactively be doing?

This lady’s asked for 40-plus, but to generally increase the likelihood of follicles responding and improved egg quality?

Dr. Deborah Ikhena-Abel

Yeah, I would say the most important lifestyle factor—if this applies to you—is to stop smoking or any kind of nicotine. That we know for sure affects how your ovaries behave, how your ovaries respond to medication. So that would be the first piece to start.

Other things that may help to improve your outcome from the cycle: as far as nutrition, the diet that has been most closely linked with improved fertility outcomes is a Mediterranean diet.

I always tell patients, I don’t think it’s because olives are better for you than apples necessarily, but it’s really because it’s a plant-based diet. It’s a diet that is really rich in fruits and vegetables, in whole foods, legumes, and also is more—like, in terms of animal protein—it’s more fish, maybe some chicken versus beef.

So all of these things we know are better for our cells, for overall health in terms of being really rich in antioxidants. And so all of those can come together to improve the outcome from a fertility treatment cycle.

As far as supplements, the one supplement that I do recommend to my patients is Coenzyme Q10, because it does have some data to suggest that it helps to improve both egg and sperm quality.

So that’s something to definitely consider. And in my patients with PCOS, I usually recommend inositol as well.

Eloise Edington
Would you recommend that patients try and start that three months before they have treatment if possible? Is there an optimal time to be prepping prior to treatment?

Dr. Deborah Ikhena-Abel

Yeah, I would say three months before is a good time. However, I would put in the caveat of, if you have a low egg count or if you’re 40 or older, I would not wait three months exclusively to get the benefit of the supplements or the lifestyle changes.

Because at that point in time, we know that there is going to be continued decline in quality over those three months, and the rate of that decline is probably going to outpace the benefits that you may get from the lifestyle changes and the supplements.

Eloise Edington 

That’s interesting. Is that another reason—going back to what you said before—about why some people might do back-to-back cycles?

Because if they were to get pregnant, they’d be waiting a whole, you know, another year or longer before potentially retrieving more eggs?

Dr. Deborah Ikhena-Abel

Exactly. And based on their age or their egg count, waiting a whole year may not be an option for them.

Eloise Edington

That’s really sound advice. Has anyone got any other questions for Dr. Debo whilst we have you here live? Please do ask.

Is there anything else you think that we should discuss that we haven’t on this topic?

Dr. Deborah Ikhena-Abel

First off, I wanted to say that this was a very—I really like the topic. I’ve never had a conversation about follicles specifically, so I thought, “Oh, this is a nice take,” and it’s a question people have all the time going through the cycle.

I think it’s important to know that when you’re thinking about follicle sizes going through an IVF cycle—I have patients who are like, “Can we wait till all the follicles are above 18 or above 16?”

One of the things to keep in mind is those follicles are not going to—the eggs in the follicles won’t be there forever.

So if you push to the point where every single follicle is above 16 or above 18, then you may get to a point where the larger follicles are now like 28 millimeters or 30 millimeters, and those eggs may start to atrophy.

Because again, these eggs are on a clock in the sense that they’re only there for a few weeks. So we want to keep that in mind when we’re making that decision.

So if your doctor’s having you take your trigger and you’re like, “Oh my gosh, I still have follicles that are 13 mm,” it’s not because they are ignoring those follicles, but they’re trying to think of the whole picture. 

Eloise Edington

What is the best point to get the best of all the follicles and avoid losing the ones that are already ahead of the pack?

Do you find that your patients are quite well-read and they’re Googling things online and coming to you asking questions based on what they’ve read?

Dr. Deborah Ikhena-Abel

I find that, for sure. I think that there are people who come to me with very good data, actually.

I had two patients who are researchers—not in medicine, but they come to me with very good data and have kind of thought about it the way that I would think about it. That’s always great, because then I can reaffirm what they’re already thinking.

And then sometimes patients will come across people online who are spreading misinformation for whatever reason—whether it’s to promote a product that they’re selling or to garner followers.

And so in that case, it’s an opportunity to kind of discuss the data that they’re presenting to me—what parts of that data may be true, what parts of it are not true—and then to explain why.

Because I think you can just say, “Oh, this isn’t true, end of discussion,” but to explain, like, “Actually, this is what is actually happening, and these are the actual factors that we’re putting into consideration.”

Eloise Edington

Absolutely. And then, of course, that’s your specialism, isn’t it—to be looking at the protocol people are on, to work out what’s happening with the follicles and how you’re changing the medication in line with that?

Dr. Deborah Ikhena-Abel

Exactly, yes. And then I think another thing I would tell patients not to do is to not compare themselves to their friend who went through IVF.

I have a lot of patients who will say, “Well, my friend went through IVF and she had 25 eggs,” and I’m like, don’t do that.

Everyone’s ovaries are different; everyone’s born with a different set of cards. And so, like they say, “Comparison is the thief of joy”—it’s a thief of joy in IVF as well. So really try to just focus on their own journey. At the end of the day, all you need is one good egg that can result in one healthy baby.

So there are people who will have fewer eggs but will be successful, and unfortunately there are people who may have more eggs but may not be successful. So really, not comparing themselves and just kind of focusing on their own journey as they go through the process.

Eloise Edington 

So it’s about quality over quantity?

Dr. Deborah Ikhena-Abel

Exactly. Quality is important.

Eloise Edington

Two more—well, another question if you have time. What are your thoughts on growth hormone for those with low AMH?

Dr. Deborah Ikhena-Abel

Yeah, so I will sometimes consider growth hormone for my patients. There is data to suggest that in women who are 40 and older, it may increase the likelihood of a live birth from going through an IVF cycle.

Now, that being said, it’s an expensive medication. It’s not covered by insurance for IVF; it’s only covered for growth hormone deficiency. And it’s not a guarantee. There are no guarantees in biology or in medicine.

So I think that’s a conversation you should have with your physician who is familiar with your course, how you’ve responded in prior cycles, and the rest of your medical history to determine if that’s something that may be beneficial for you or not.

But it’s something that I do discuss with my patients, especially if they’re 40 and older and/or have a lower egg count.

Eloise Edington

That’s a great question, and that’s really insightful. Thank you so much for sharing that.

If anyone else has any other questions for Dr. Debo and would like to find out more, please do head to our link in bio.

The team at Aspire Fertility in Austin would love to help you, and we’ve also linked up the Prelude Network so that you can have a look at all of the clinics across North America to find what suits you best and speak to a specialist to get some personalized advice and treatment started.

Eloise Edington

So thank you so much for your time—really, really appreciate it. And I believe I’ll be meeting you very soon. I’m coming over to Austin, Texas in a couple of weeks to visit the clinic, so very much looking forward to seeing you in person as well.

Dr. Deborah Ikhena-Abel

Same here, same here. Thank you for having me.

Eloise Edington

Thank you, everyone, for joining. It was a pleasure chatting with you.

Dr. Deborah Ikhena-Abel

Thanks, bye.

Eloise Edington

Thanks, bye-bye.

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