Endometriosis and IVF: Why Your Response to Stimulation May Be Different — And How to Plan Around It

What Endometriosis Actually Does to Your Ovaries

Endometriosis is not just a painful condition — it is one that quietly affects fertility in multiple ways. Most people know that endometriosis can cause blocked tubes or distort the uterine cavity. But one of the less-discussed effects is what it does to your ovarian reserve and your response to IVF stimulation.

When endometriosis tissue grows on or near the ovaries, it can form fluid-filled cysts called endometriomas. These cysts are not harmless bystanders. The fluid inside them contains iron compounds and free radicals that are toxic to the surrounding ovarian tissue. Over time, this damages the follicles that hold your eggs — reducing both the quantity and quality of eggs available for retrieval.

Even in women with endometriosis who do not have visible cysts, the chronic inflammation associated with the condition can affect the environment around developing follicles. This is why many women with endometriosis find that their AMH (anti-Müllerian hormone) is lower than expected for their age, and why their ovaries sometimes respond differently during an IVF stimulation cycle.

How Endometriosis Changes Your IVF Stimulation Response

During a standard IVF cycle, you will take injectable hormones to stimulate your ovaries to produce multiple follicles. For most women, this process is fairly predictable. For women with endometriosis, particularly those with endometriomas or a history of ovarian surgery, the picture can be more complicated.

Here is what you might experience:

• Lower egg numbers: Endometriosis — especially when it has involved the ovaries — can reduce the number of follicles that respond to stimulation. This is not a failure of the process; it is a reflection of reduced ovarian reserve caused by the condition itself.
• Asymmetric response: If one ovary has been more affected by endometriosis or surgery than the other, you may notice one ovary producing more follicles than the other during monitoring scans.
• Egg quality concerns: The inflammatory environment created by endometriosis can impair egg maturation. This does not mean all eggs will be affected, but your fertility team will monitor maturity and fertilisation rates carefully.
• Higher medication requirements: Some women with endometriosis need higher doses of stimulation medication to achieve an adequate response, though this is always titrated carefully to avoid overstimulation.

Understanding these nuances in advance allows your doctor to design a protocol that accounts for your specific situation — rather than applying a standard approach that may not serve you as well.

Should Endometriomas Be Removed Before IVF?

This is one of the most debated questions in reproductive medicine, and the honest answer is: it depends.

The concern with operating on endometriomas before IVF is that surgery itself can damage the healthy ovarian tissue surrounding the cyst — further reducing ovarian reserve. Multiple studies have shown that women who have had repeated ovarian surgeries for endometriomas often have a significantly diminished response to stimulation afterwards.

On the other hand, very large endometriomas (generally over 4 cm) can physically obstruct egg collection, increase the risk of infection during retrieval, and may impair the quality of surrounding follicles. In these cases, your specialist may recommend drainage or surgical removal before proceeding.

The decision should always be individualised. At Iswarya Fertility, our specialists review each patient's scan findings, AMH levels, surgical history, and overall fertility plan before recommending whether intervention is appropriate prior to IVF. There is no single right answer — only the right answer for you.

Choosing the Right IVF Protocol When You Have Endometriosis

Not all IVF stimulation protocols are the same, and for women with endometriosis, protocol selection can meaningfully affect outcomes.

The Long Downregulation Protocol

Traditionally, the long agonist protocol has been favoured for women with endometriosis. This involves suppressing the pituitary gland for a period before stimulation begins. The extended suppression phase can help reduce endometriosis-related inflammation, improve the uterine environment, and may modestly improve egg quality. Some research suggests a prolonged downregulation period of two to three months using a GnRH agonist before IVF may be beneficial for women with moderate to severe endometriosis.

The Antagonist Protocol

The antagonist protocol is shorter and more flexible, often preferred for women with lower ovarian reserve — including many women with endometriosis — because it reduces the risk of over-suppression. Your doctor will weigh the benefits of each approach based on your reserve markers and individual profile.

Freeze-All Cycles

For women with endometriosis, a freeze-all strategy — where all embryos are frozen and transferred in a subsequent cycle — is often recommended. Endometriosis can affect endometrial receptivity at the time of egg retrieval, and a frozen embryo transfer in a carefully prepared cycle may offer better implantation conditions. This is something the team at Iswarya Fertility considers for many patients with endometriosis when planning their transfer strategy.

What You Can Do to Support Your IVF Outcome

While endometriosis does introduce genuine challenges, there is meaningful evidence that certain steps can improve your IVF outcomes:

1. Begin your fertility assessment early. Given that endometriosis progressively affects ovarian reserve, earlier IVF planning generally means more eggs available. If you have been diagnosed with endometriosis and are thinking about starting a family, do not wait to get your AMH and antral follicle count checked.
2. Discuss anti-inflammatory approaches with your doctor. Some specialists recommend a brief course of hormonal suppression therapy before IVF to quieten endometriosis activity. The evidence here is nuanced, but it is worth discussing in your consultation.
3. Optimise your general health. A Mediterranean-style diet, reducing alcohol, managing stress, and maintaining a healthy weight have all been associated with improved fertility outcomes — and are particularly relevant in the context of a condition driven by inflammation.
4. Be realistic but hopeful about egg numbers. Many women with endometriosis go on to have successful IVF cycles and healthy pregnancies. Fewer eggs does not mean zero chance — it means working strategically with what your body can provide.

Speak to a Specialist Who Understands Endometriosis-Related Fertility

Endometriosis and IVF require a level of personalisation that goes beyond standard fertility care. The protocol choices, surgical decisions, and transfer strategies all need to account for the unique ways this condition interacts with your reproductive system.

At Iswarya Fertility, our team has extensive experience supporting women with endometriosis through every stage of the fertility journey — from initial assessment and diagnosis to tailored IVF protocols and embryo transfer planning. If you have been diagnosed with endometriosis and are unsure how it affects your fertility options, we encourage you to book a consultation with one of our specialists. The right information, given at the right time, can make all the difference.

Frequently Asked Questions

Can I still do IVF if I have endometriosis?

Yes, absolutely. Endometriosis does present some added challenges during IVF — particularly around ovarian response and egg numbers — but many women with endometriosis go on to have successful cycles and healthy pregnancies. The key is working with a specialist who can tailor your protocol to your specific situation.

Does having an endometrioma mean I need surgery before IVF?

Not always. The decision depends on the size of the cyst, your current ovarian reserve, and your surgical history. Small endometriomas are often monitored rather than operated on before IVF, because surgery itself can reduce ovarian reserve. Your specialist will advise based on your individual scan findings and AMH levels.

Why is my AMH low if I have endometriosis?

Endometriosis — especially when it involves the ovaries — can damage the follicles that produce the AMH hormone. The toxic environment created by endometrioma fluid and chronic inflammation gradually reduces the pool of healthy follicles, which is reflected in a lower AMH reading. This is why early fertility assessment is important for women with this diagnosis.

Is a frozen embryo transfer better than a fresh transfer when you have endometriosis?

For many women with endometriosis, a freeze-all strategy followed by a frozen embryo transfer in a subsequent cycle is preferred. This is because endometriosis can affect the uterine lining's receptivity at the time of egg retrieval, and a separately prepared transfer cycle may offer better conditions for implantation.

How many eggs should I expect to get during IVF if I have endometriosis?

This varies widely depending on the severity of the condition, whether you have had prior ovarian surgery, and your current ovarian reserve markers like AMH and antral follicle count. Women with endometriosis may produce fewer eggs than average, but even a small number of good-quality eggs can lead to a successful outcome with the right protocol and transfer strategy.