Endometriosis and fertility: how it affects conception and what your options are

Trying to conceive · Updated July 2026 · All articles

How endometriosis can affect fertility

Endometriosis occurs when tissue similar to the lining of the uterus grows outside it, most commonly on the ovaries, fallopian tubes and the tissue lining the pelvis. This misplaced tissue responds to monthly hormonal changes just as the uterine lining does: it thickens, breaks down and bleeds, but has nowhere to go. Over time this can cause inflammation, scar tissue and adhesions.

The impact on fertility varies considerably. Adhesions can distort the pelvis and block or partially obstruct the fallopian tubes, making it harder for eggs and sperm to meet. Endometriomas (ovarian cysts filled with old blood, sometimes called chocolate cysts) can reduce ovarian reserve and damage the surrounding ovarian tissue. There is also growing evidence that the inflammatory environment associated with endometriosis may affect egg quality and implantation.

Not everyone with endometriosis has difficulty conceiving. Around 70 to 80 percent of people with mild to moderate disease conceive without medical assistance over time. The diagnosis is not a barrier to pregnancy for most people, but it does mean understanding your specific situation rather than applying a generic prognosis.

The four stages and what they mean for your chances

Endometriosis is classified into four stages (I to IV) by the American Society for Reproductive Medicine, based on the location, depth, extent and size of lesions, and the presence of adhesions. Stage I (minimal) and stage II (mild) involve small implants and few or no adhesions. Stages III (moderate) and IV (severe) involve deeper or more extensive disease, larger endometriomas and significant adhesions.

The staging system does not perfectly predict fertility outcomes, which can be frustrating. Some people with stage IV disease conceive naturally, while others with stage I disease have unexplained difficulty. Stage broadly correlates with the degree of anatomical disruption, but other factors including age, sperm quality and egg quality are equally important.

What the stage does help with is guiding treatment decisions. Mild disease may warrant a period of expectant management or IUI. Moderate to severe disease, particularly if tubes are affected or ovarian reserve is already reduced, is more likely to lead to an earlier recommendation for IVF.

Conceiving naturally with endometriosis

If your tubes are open and ovarian reserve is adequate, trying to conceive naturally for a defined period is a reasonable first step for mild to moderate endometriosis. The recommended period before seeking further help may be shorter than the standard 12 months: many specialists suggest 6 months given the nature of the condition.

Timing intercourse around ovulation remains relevant and useful. Tracking ovulation with basal body temperature and LH tests helps ensure the fertile window is not missed, which matters especially if the condition is already reducing your overall odds per cycle.

It is worth having an open conversation with a gynaecologist or fertility specialist about your specific situation, even during a period of natural trying. Understanding your tubal status and ovarian reserve from the outset means you will not spend time trying naturally if the anatomy makes it unlikely, and gives you a clearer plan if conception does not happen within the agreed window.

When laparoscopic surgery is considered

Laparoscopy is both the definitive diagnostic procedure for endometriosis and a potential treatment. During the procedure a surgeon can remove or ablate visible endometriosis deposits and cut through adhesions. For moderate to severe disease, surgery can improve natural conception rates by restoring more normal pelvic anatomy.

The decision about whether to operate before trying to conceive or before IVF is not straightforward. Surgery has benefits in terms of symptom relief and sometimes fertility, but it also carries risks including reduced ovarian reserve, particularly when endometriomas on the ovaries are removed. Removing an endometrioma can damage the healthy ovarian tissue surrounding it, and repeat surgery carries higher risk of cumulative reserve loss.

Most fertility specialists recommend a careful individualised assessment before surgery when pregnancy is the goal. If ovarian reserve is already reduced, the priority may shift away from surgery and towards IVF. If tubes are blocked, surgery to open them may or may not be worthwhile depending on the extent of the adhesions involved.

When IVF is recommended

IVF bypasses the fallopian tubes entirely and is particularly relevant when tubes are blocked or severely damaged, when there is moderate to severe endometriosis affecting conception, when natural conception has not occurred after an appropriate period of trying, or when ovarian reserve is already reduced.

IVF outcomes for people with endometriosis are slightly lower than for those without, but success rates are still meaningful and IVF remains an effective path to parenthood. The reduction in odds is more pronounced in severe disease and in people who have already had multiple surgeries that have affected ovarian reserve.

Some fertility clinics recommend a course of hormonal therapy (such as GnRH analogues) for several months before an IVF cycle to suppress active endometriosis. The evidence base for this strategy is mixed, and it is worth asking your team specifically what they recommend for your situation and why.

Your timeline and decisions after diagnosis

Finding out you have endometriosis when you are trying to conceive can feel like a lot of information to absorb at once. The diagnosis raises questions about timing, surgery, treatment and what the journey ahead might look like. Try to take it one step at a time and avoid making major decisions in the immediate aftermath of a diagnosis.

A useful first step is a specialist appointment to assess your tubes and ovarian reserve. These two pieces of information shape almost every subsequent decision. If both are in reasonable order, you have time. If one or both are significantly affected, you will want to move sooner rather than waiting.

Age is always relevant but is especially important with endometriosis, since both the condition and increasing age affect ovarian reserve simultaneously. If you are in your mid to late 30s, a shorter waiting period before moving to fertility treatment is often sensible.

The emotional weight of this journey

Endometriosis is a condition that has historically been under-recognised and under-treated. Many people spend years in pain before receiving a diagnosis. Being told it may be affecting your fertility, after years of difficult symptoms, can compound a sense of loss and unfairness that is entirely understandable.

You may also find yourself in the position of explaining your situation to people who do not understand endometriosis, or who minimise the fertility implications. Finding clinicians who take the condition seriously and who communicate clearly with you is part of the process, not a luxury.

Support networks, whether through organisations like Endometriosis UK, peer communities online or counselling, can make a real difference when medical decisions feel overwhelming. You do not have to carry this alone, and being well-supported helps you make clearer decisions about treatment.

Frequently asked questions

Does endometriosis always affect fertility?

No. Many people with endometriosis, particularly mild to moderate disease, conceive naturally without any treatment. Around 70 percent of people with mild endometriosis will conceive naturally over time. The diagnosis reduces overall odds but is not a barrier to pregnancy for most people.

Can I conceive naturally with stage 3 or 4 endometriosis?

It is harder but not impossible. Severe endometriosis is associated with greater anatomical disruption such as blocked tubes or large ovarian cysts, which can significantly reduce natural conception rates. IVF is more commonly recommended for severe disease, but outcomes depend on many individual factors including age and ovarian reserve.

Does removing endometriosis through surgery improve fertility?

For moderate to severe endometriosis, laparoscopic surgery to remove adhesions or deposits can improve natural conception rates. For mild disease the evidence is less clear. Ovarian cystectomy for endometriomas may slightly reduce ovarian reserve, which is one reason surgery decisions need to be made carefully with a specialist when pregnancy is the goal.

Does IVF work as well for people with endometriosis?

IVF success rates are slightly lower for people with endometriosis compared to those without, particularly in severe disease. However, IVF remains an effective treatment option and success rates are still meaningful. Your specific stage, age and ovarian reserve all influence the picture.

Will pregnancy cure endometriosis?

No. Pregnancy can temporarily suppress endometriosis symptoms, and some people notice improvement after giving birth, but endometriosis is not cured by pregnancy. It typically returns after childbirth when menstrual cycles resume.

How do I know if endometriosis is affecting my fertility?

The only definitive way to diagnose endometriosis is through laparoscopy, though ultrasound can detect ovarian endometriomas. If you have not conceived after 6 to 12 months of trying and have symptoms such as painful periods or pain during sex, it is worth raising endometriosis as a possible cause with your GP or gynaecologist.

This article is for general information only. If you have concerns about your fertility or reproductive health, speak to your GP or a fertility specialist.