Fibroids in Pregnancy

Fibroids are common, non-cancerous growths in the muscle of the womb. Many women have them and never know. In pregnancy they can cause no trouble at all, but sometimes they cause pain or complications. This page explains the types of fibroids, what symptoms to watch for, and how they are managed in pregnancy in the UK.

What fibroids are

Fibroids are benign tumours of uterine smooth muscle. They can be submucosal, intramural, subserosal, or pedunculated, and their position affects whether they matter in pregnancy. They are more common in women in their thirties and forties and can grow during pregnancy due to hormones, then shrink afterwards. If you have fibroids and are planning a caesarean, your surgical team will review your scans to plan the safest approach. Fibroids can increase blood loss during surgery, so preparation is important.

Symptoms and complications

Most fibroids in pregnancy cause no symptoms. Red degeneration, where a fibroid outgrows its blood supply, can cause sudden pain, usually in the second trimester. Fibroids can increase the risk of early bleeding, breech position, growth problems, and caesarean birth, depending on size and location. Large lower-segment fibroids can block the birth canal. Red degeneration, while painful, is not dangerous to the baby. The pain usually settles within a few days to a week, and the fibroid often shrinks afterwards. Your team can offer pain relief appropriate to pregnancy.

How fibroids are monitored

Fibroids are usually found at the dating scan and noted in your records. Growth scans may be offered to track both the baby and fibroids. Your team will consider position and size when planning birth. If a fibroid is in the lower uterus, a caesarean may be recommended; this is a planned decision, not an emergency one. If you have been diagnosed with fibroids before pregnancy, mention this at your booking appointment. Your midwife can ensure it is noted and plan appropriate monitoring from the start.

Management

Pain from degeneration is usually managed with paracetamol and rest; stronger options may be used if needed. Surgery to remove fibroids is not normally done in pregnancy. If a caesarean is needed, fibroids are usually left in place unless one is easily accessible and causing issues. After pregnancy, fibroids often shrink, and further treatment, if ever needed, can be planned outside of pregnancy. After pregnancy, fibroids often shrink as hormone levels fall. If they were causing symptoms before, you may find they improve. If not, treatment options can be discussed with your GP outside of pregnancy.

This page is for general information only and does not replace advice from your UK maternity or mental health team. If you are worried about your physical or mental health in pregnancy, contact your midwife, GP, or call 111. In an emergency, call 999.