Two of the most common reproductive conditions in women, endometriosis and fibroids, also happen to be two of the most likely to be missed, dismissed, or diagnosed years after symptoms first appear. Both can affect fertility, although neither makes pregnancy impossible and understanding how they interact with conception helps you plan rather than panic.
Endometriosis and Fertility
Endometriosis is a condition in which tissue similar to the lining of the uterus grows outside the uterus, often on the ovaries, fallopian tubes, the bowel, the bladder, or the pelvic wall. It affects around one in ten women of reproductive age and is one of the leading causes of pelvic pain and infertility, although many women with endometriosis have no fertility difficulty at all.
Endometriosis can affect fertility in several ways:
Inflammation: The lesions create chronic pelvic inflammation, which interferes with egg quality, sperm function, fertilisation, and implantation.
Adhesions and scarring: The body’s response to endometriosis lesions can produce scar tissue that distorts pelvic anatomy, blocks fallopian tubes, or restricts ovarian function.
Ovarian endometriomas: Cysts of endometrial-like tissue on the ovaries (sometimes called chocolate cysts) can reduce ovarian reserve and affect egg quality.
Altered uterine receptivity: Endometriosis appears to affect the uterine lining in ways that can make implantation less likely.
Around 30 to 50 per cent of women with endometriosis experience some difficulty conceiving, although many conceive naturally and many more conceive with support. The severity of endometriosis does not always correlate with fertility impact, which is one of the frustrating realities of the condition.
Options to Consider
If you have endometriosis and want to conceive, current evidence supports a few clear directions. Surgical removal of endometriosis lesions (excision rather than ablation, ideally by a specialist) can improve natural conception rates, particularly in moderate to severe disease. IVF is often recommended where natural conception is unlikely or time is a factor. Hormonal suppression treatments used to manage endometriosis pain are not used while trying to conceive.
If you have endometriosis and are not yet ready to try, fertility preservation through egg freezing is worth discussing, particularly if you have endometriomas or if surgery is planned that may affect ovarian reserve.
Fibroids and Fertility
Fibroids are non-cancerous growths that develop in or on the wall of the uterus. They are very common, affecting up to 70 per cent of women by age 50, with higher prevalence and earlier onset in Black women. Many fibroids cause no symptoms and have no effect on fertility. Others can cause heavy bleeding, pelvic pain or pressure, and difficulty conceiving or carrying a pregnancy.
Whether a fibroid affects fertility depends largely on three things: where it is, how big it is, and how many there are.
Submucosal fibroids: These grow into the uterine cavity and are the most likely to interfere with fertility and implantation. Removal usually improves outcomes.
Intramural fibroids: These grow within the muscle wall of the uterus. Their effect on fertility depends on size and whether they distort the cavity.
Subserosal fibroids: These grow on the outside of the uterus and rarely affect fertility, although large ones may cause symptoms.
Fibroids can also raise the risk of miscarriage, preterm birth, abnormal foetal positioning, and the need for caesarean section, again depending on size and location.
Options to Consider
Treatment depends on symptoms, fibroid characteristics, and whether you want to conceive. Myomectomy (surgical removal of fibroids while preserving the uterus) is the option most compatible with future fertility. Uterine artery embolisation is generally not recommended for women who want future pregnancies. Hormonal treatments and ablation procedures may help symptoms but are not used while trying to conceive.
Regular monitoring with ultrasound is reasonable for fibroids that are not causing symptoms and not affecting the uterine cavity.
Planning Ahead
If you have either condition, three things tend to make the biggest difference. First, work with a clinician who specialises in the condition rather than treating it as a side note.
Endometriosis and fibroid care vary widely in quality. Second, do not wait the full 12 months before seeking help if you are trying to conceive. Earlier conversations open up earlier options. Third, ask specifically about fertility preservation if relevant, especially if surgery is being discussed.
Neither condition makes pregnancy impossible. Both make information and planning more useful than usual.