Endometriosis and Fertility: How It Affects Conception and Where IVF Fits

Endometriosis is a condition where tissue similar to the lining of the womb grows in other parts of the body, usually around the pelvis, and it can affect fertility through inflammation, scarring, and adhesions. It does not mean you cannot get pregnant: many people with endometriosis conceive, with or without help. This guide explains how it affects fertility, why diagnosis is so often delayed, and where IVF fits in.

What endometriosis is, and how common it is

Endometriosis is one of the most common gynaecological conditions, affecting roughly 1 in 10 women of reproductive age, according to the NHS. The womb-like tissue can settle on the ovaries, fallopian tubes, and the lining of the pelvis, where it responds to your monthly hormone cycle: it builds up and breaks down, but unlike a period it has no way to leave the body. Over time that can cause inflammation, cysts, and bands of scar tissue called adhesions.

It is a leading cause of subfertility, which is why we treat it as one of the key causes of infertility. Symptoms vary widely: some people have severe pain, others have very little, and the amount of pain does not reliably predict the effect on fertility.

How endometriosis affects fertility

Endometriosis can reduce fertility in several ways at once, though many people still conceive. Adhesions and scarring can distort the pelvis or block or damage the fallopian tubes, making it harder for an egg and sperm to meet. Endometriosis cysts on the ovaries (endometriomas) can affect egg supply and quality, and the inflammatory environment it creates may make implantation less likely. The American Society for Reproductive Medicine notes that endometriosis is strongly associated with infertility while stressing that the link is not absolute.

For the year before my own diagnosis, every negative test felt like a personal failure of willpower, as if I simply was not relaxing enough. Learning that there was a physical reason behind it, something with a name, was oddly steadying. It did not fix anything overnight, but it moved me from self-blame to a plan, and that mattered more than I expected.

Why diagnosis is so often delayed

Diagnosis of endometriosis is frequently delayed, on average by several years from the first symptoms, because painful and heavy periods are so often dismissed as normal. This delay is one of the most important things to know, because fertility can be time-sensitive and the years lost to a missed diagnosis are years you cannot get back.

The usual path starts with your symptoms and a pelvic examination, often followed by an ultrasound or MRI scan. The most definitive test is laparoscopy: a keyhole operation under general anaesthetic that lets a surgeon see the tissue directly and often treat it in the same procedure. If you have persistent period pain, pain during sex, or pain that stops you doing everyday things, raise it with your GP rather than waiting. The same applies if you have been trying to conceive without success: please see a doctor about your fertility sooner rather than later.

Tests and investigations

If endometriosis may be affecting your fertility, your team will look at the whole picture, not just the endometriosis. Investigations typically check that your fallopian tubes are open, assess your ovarian reserve (egg supply) with blood tests and a scan, and include a semen analysis for a male partner, because more than one factor is common. Our guide to fertility tests and investigations walks through each of these. NICE guideline NG73 recommends a personalised assessment rather than assuming endometriosis is the only issue.

Treatment options, and where IVF fits

Treatment for endometriosis-related infertility is tailored to you, and there is no single right answer. The main routes are:

• Laparoscopic surgery to remove or destroy endometriosis tissue, which can improve the chance of conceiving naturally, particularly with milder disease.
• Assisted conception, where IVF is often effective and is commonly recommended when surgery has not worked, when time matters because of age, or when more than one fertility factor is present.

Hormone treatments that suppress periods help with pain but do not improve fertility while you are taking them, because they also prevent conception. For many people the practical question becomes when to move to IVF. Endometriosis can lower IVF success somewhat in severe cases, but many people with the condition have successful cycles, and age remains the strongest single predictor of IVF success. Your specialist can weigh the options against your age, symptoms, and test results.

The emotional weight of all this is real, and worth naming. If it is wearing you down, our guide to the emotional side of fertility treatment may help.

This is general information and support, not medical advice. For a diagnosis or a treatment plan that fits you, please consult your GP or a fertility specialist.