Ultrasound shows 10 follicles — why were only 6 eggs retrieved? The number of eggs retrieved in IVF is truly determined by these 3 factors

"The ultrasound clearly showed quite a few follicles — so why didn't we end up with that many eggs?" This is a question that many families entering the stimulation phase of IVF find themselves asking. For women with low AMH, a limited number of antral follicles, or more advanced age, every single egg can feel especially precious. As a result, many people focus on one question:

Is there a way to retrieve more eggs from a single stimulation cycle?The answer is not simply "more injections, more medication." When ovarian reserve is essentially fixed, we cannot create more eggs out of thin air. What is worth focusing on instead is using a more rational stimulation strategy to make the most of the follicles that had a chance to grow in that cycle.

For families planning third-generation IVF in Thailand, seeking fertility treatment overseas, or pursuing cross-border childbirth, understanding this logic in advance can also help you better understand why your doctor recommends different protocols during consultation.

1. First, let's clarify: does the number of follicles seen on ultrasound guarantee the same number of eggs retrieved?

Not necessarily. The core purpose of ovarian stimulation is to use medication to provide controlled stimulation to the ovaries, giving follicles that would normally have only a few continuing to grow in a cycle the opportunity to develop together. But here's the issue — not every follicle grows at exactly the same rate. Under the same gonadotropin stimulation (such as FSH), some follicles respond sensitively and grow quickly; others respond more slowly; and some may gradually fall behind throughout the process. Therefore, stimulation does not simply "copy and paste" every antral follicle seen on ultrasound into a mature egg that can ultimately be retrieved.

The doctor needs to observe a combination of factors:

• The number and size of follicles;
• Whether follicle growth is synchronized;
• Changes in hormone levels such as estrogen;
• The ovaries' actual response to medication;
• Previous stimulation history;
• Age and ovarian reserve status.

These factors together determine when to move to the next stage. So, the number of follicles seen on ultrasound is only a阶段性 reference and cannot be directly equated with the final number of eggs retrieved. This is why some people may see around 10 follicles during monitoring but end up with fewer eggs than that.

2. The first key factor that truly affects egg yield: ovarian reserve

When discussing egg yield, two very important indicators cannot be avoided: AMH and AFC.

1. What is AMH?

AMH, or anti-Müllerian hormone, is one of the commonly used indicators for assessing ovarian reserve. In simple terms, you can think of the follicle reserve in your ovaries as an "account." AMH can help a doctor, to a certain extent, determine the current reserve status of that account. Generally speaking, as age increases, the follicle pool is gradually depleted, and AMH levels tend to decline overall.

But it's important to avoid a common misconception here: higher AMH is not necessarily better, and a single AMH value cannot determine whether IVF will ultimately succeed. For example, women with polycystic ovary syndrome (PCOS) may have higher AMH levels, but this does not mean their egg quality is necessarily better.

Similarly, a low AMH level does not mean "there is no chance at all." One of its more important roles is helping the doctor predict how the ovaries are likely to respond to stimulation medication, thereby providing a reference for protocol design.

2. What is AFC?

AFC stands for antral follicle count. It refers to the number of antral follicles that can be observed in both ovaries via ultrasound in the early phase of the menstrual cycle.

If AMH is like an "inventory reference," then AFC is more like the "pool of participants available for this cycle" that the doctor sees before the cycle begins. Therefore, AMH and AFC are usually assessed together. For families preparing for overseas fertility treatment or third-generation IVF in Thailand, doctors often focus on these two indicators during the initial assessment precisely because they provide important reference points for the subsequent stimulation protocol.

3. The second key factor: higher medication doses do not necessarily mean more eggs

This is a misunderstanding that many people easily fall into. Some women whose first stimulation cycle didn't go as expected may think: "Was my dose too low?" "If I increase the dose next time, will I get more eggs?" In reality, how many follicles the ovaries can recruit is itself limited by factors such as ovarian reserve.

Increasing the stimulation medication dose does not mean the number of eggs retrieved can increase indefinitely. Especially for women with low ovarian reserve, if the ovaries already have a limited response to gonadotropins, simply increasing the dose may not necessarily yield more follicles as expected.

What truly matters is: what kind of protocol is better suited to the current state of your ovaries. This brings us to the third important factor that affects egg retrieval efficiency — the stimulation protocol itself.

4. The third key factor: different stimulation protocols, different approaches

There is no "one-size-fits-all" stimulation protocol in IVF. Because age, AMH, AFC, and previous stimulation responses all differ, the protocol a doctor chooses will naturally differ as well. Common protocols include the long protocol, the antagonist protocol, and the mild stimulation (minimal stimulation) protocol.

Long protocol: emphasizes follicle synchronization

One important feature of the long protocol is that it first uses down-regulation to control endogenous hormones, then uses exogenous gonadotropins to promote the growth of multiple follicles together.

One of its advantages is that it allows a cohort of follicles to develop as synchronously as possible. For some women with normal ovarian reserve, a doctor may consider this protocol based on their individual condition. However, there is no absolute "best" protocol. If ovarian reserve has already declined and the response to stimulation medication is limited, whether a stronger down-regulation strategy is appropriate requires careful evaluation by the doctor.

Antagonist protocol: more flexible cycle scheduling

The antagonist protocol is also one of the commonly used stimulation strategies in assisted reproduction today. Typically, gonadotropins are used in the early part of the cycle to promote the growth of multiple follicles. Once a certain stage is reached, a GnRH antagonist is added to prevent a premature LH surge, thereby reducing the risk of early ovulation.

One of the features of this protocol is that the cycle is relatively flexible and does not require the extended down-regulation period of the long protocol. However, during stimulation, follicles may still develop at slightly different rates, so the doctor will continuously adjust based on ultrasound and hormone results. This is why frequent monitoring is needed during an IVF cycle. The doctor is not simply "checking how big the follicles have grown" — they are dynamically deciding the next medication step based on each round of test results.

Mild stimulation protocol: the focus may not be on "getting the most in one cycle"

If the AFC is low and ovarian reserve is diminished, the number of antral follicles that can participate in growth in one cycle is itself limited, so the approach may change. In such cases, doctors sometimes consider a gentler stimulation strategy. The mild stimulation protocol typically uses lower medication doses. Its core logic is not to forcibly pursue "getting many eggs in one cycle," but rather to develop a more appropriate strategy based on the patient's ovarian reserve and actual response. For some women with low ovarian reserve, rather than fixating solely on the number of eggs retrieved in a single cycle, it may be more meaningful to evaluate things from the perspective of multiple cycles, cumulative embryo numbers, and overall time investment. Of course, which protocol to use ultimately needs to be decided by a reproductive doctor based on individual circumstances.

5. A disappointing first stimulation cycle doesn't mean the second will be the same

Your first stimulation cycle actually provides very important information: the doctor can see exactly how your ovaries respond to medication.

For example: some women's follicles grow very evenly in the early stage; some develop one or two dominant follicles that clearly pull ahead; some may recruit only a limited number of follicles even with increased medication; and others may not respond well to a particular protocol. All of this information becomes an important basis for adjusting the protocol in the next cycle.

So, if the number of eggs retrieved in the first cycle did not meet expectations, it does not necessarily mean you will only ever get the same result. The doctor may reassess the medication type, dosage, start timing, the timing of LH surge suppression, and the trigger strategy based on how your body actually responded in the previous cycle. The value of individualized stimulation lies precisely in this dynamic adjustment.

6. Conventional stimulation vs. mild stimulation: how should you choose?

Many people preparing for IVF like to ask directly: "Is conventional stimulation better, or is mild stimulation better?" The truth is, there is no single answer to this question. If ovarian reserve is good and the antral follicle count is relatively adequate, the doctor may focus on fully recruiting follicles within a single cycle.

For women with diminished ovarian reserve and fewer antral follicles, the strategy may focus more on the efficiency of utilizing the limited follicles available and how to arrange multiple cycles. So what should really be compared is not just:

"How many eggs can I get this time?"

You should also consider: Given my ovarian condition, what protocol can achieve a more reasonable overall outcome? These two questions may seem similar, but they reflect completely different ways of thinking.

7. Can eating certain foods or taking supplements suddenly increase egg count?

This is also a question we hear frequently during overseas medical accompaniment. Unfortunately, a woman's primordial follicle reserve cannot be "increased out of thin air" by eating a particular food, taking supplements, or through short-term lifestyle adjustments.

Therefore, be cautious if someone tells you: "Take this and your AMH will rise quickly." Or "With one month of调理 you'll grow many more follicles." Claims like these deserve careful scrutiny.

It's important to distinguish between two concepts: ovarian reserve itself and the state your body shows in a particular cycle are not exactly the same thing. Maintaining regular sleep, a balanced diet, avoiding smoking and excessive alcohol, maintaining a healthy weight, and managing underlying health conditions according to your doctor's advice are all meaningful for conception and overall health. But the goal of these efforts is not to "manufacture new eggs."

8. Does a higher number of retrieved eggs mean a higher IVF success rate?

Not necessarily. This is a point that deserves particular emphasis in this article. The number of eggs retrieved is only the first step in the entire IVF process.

What follows includes: mature eggs → fertilization → embryo culture → blastocyst formation → PGT testing when indicated → embryo transfer.

Especially in third-generation IVF in Thailand, many families also learn about PGT-related options based on medical indications and their doctor's recommendations. Therefore, what truly deserves attention is never just "how many eggs were retrieved," but how many embryos with further culture and transfer potential are ultimately obtained.

Quantity matters, but quality matters just as much. Chasing an impressive egg count for its own sake is not the true goal of IVF treatment.

9. Preparing for third-generation IVF in Thailand: what should you focus on in the early stages?

For families planning overseas fertility treatment or cross-border childbirth, Global New Life recommends not fixating anxiously on a single AMH number in the early stages. Before your actual consultation, try to prepare as complete a set of baseline information as possible — such as recent AMH, baseline hormones, transvaginal ultrasound AFC, and records from any previous IVF cycles.

If you have undergone stimulation before, details such as the protocol used, the approximate daily dosage, the number of days of stimulation, the final number of eggs retrieved, the number of mature eggs, and the fertilization and embryo culture results are all extremely valuable reference points. This information helps the doctor build a more complete picture of your past ovarian response, rather than assessing from scratch.

For those traveling to Thailand for the first time, who may face language barriers or be unfamiliar with hospital procedures, Global New Life also provides overseas medical accompaniment, translation support, appointment coordination, and travel arrangement assistance to help you complete each step with greater clarity.

A final note: what's truly worth pursuing is not "the more, the better"

When it comes to the number of eggs retrieved in IVF, let's summarize three key points:

IVF has never been a competition of sheer "numbers." For families considering third-generation IVF in Thailand, overseas fertility treatment, or cross-border childbirth, rather than becoming overly anxious about a single number, it's better to first fully understand your own physical foundation, and then work with a professional reproductive doctor to develop a protocol that truly fits your individual situation.

Global New Life hopes that through ongoing educational content and overseas medical accompaniment services, every family traveling to Thailand can face check-ups, consultations, and protocol decisions with less information asymmetry and more clarity and confidence.

This article is intended for educational purposes on assisted reproduction and for sharing information about seeking fertility treatment in Thailand. Specific stimulation protocols, medication, and cycle arrangements should be evaluated by a reproductive doctor based on individual test results.