Fibroid in Pregnancy
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Direct answer
Fibroid in pregnancy is a leiomyoma coexisting with a pregnancy, and fibroids are the commonest pelvic tumour found in pregnant women. Most fibroids cause no harm, but they can produce red degeneration, malpresentation, obstructed labour when lower-segment or cervical, preterm labour and postpartum haemorrhage. Most need only observation, and surgery is reserved for obstruction, uncontrolled bleeding or suspicion of malignancy.
What you must remember
- Growth: oestrogen stimulates fibroid growth in pregnancy, so some enlarge, and most shrink after delivery.
- Red degeneration: a common complication, causing sudden focal pain and tenderness, usually in the second trimester, with preserved fetal wellbeing.
- Malpresentation: breech or transverse lie is more frequent, depending on where the fibroid sits in the uterus.
- Obstructed labour: lower-segment or cervical fibroids block the birth canal, making caesarean delivery necessary, usually planned near term.
- Other complications: miscarriage, preterm labour, fetal growth restriction and postpartum haemorrhage from uterine atony.
- Myomectomy at caesarean: considered only for an accessible fibroid that obstructs delivery or threatens major bleeding, not for routine removal of large intramural fibroids.
A stepwise plan for a pregnant woman with pain at 26 weeks
A 31-year-old woman at 26 weeks has a 7 cm lower-segment fibroid, sudden left lower abdominal pain and a temperature of 38 degrees Celsius. Her fetal heart rate is normal, and the picture suggests red degeneration rather than labour or abruption. The steps below show how the fibroid is located, managed and delivered safely.
- Locate the fibroid: Ultrasound records position, size and relation to the cervix and placenta, which predicts malpresentation and obstruction.
- Recognise red degeneration: Sudden focal pain, tenderness and low-grade fever with a raised white count suggest red degeneration, whereas abruption brings bleeding and fetal compromise.
- Treat conservatively: Analgesia, bed rest, hydration and monitoring usually settle red degeneration, and surgery is avoided during pregnancy.
- Plan the delivery route: A lower-segment or cervical fibroid that blocks the birth canal calls for elective caesarean, planned near term.
- Decide on myomectomy at caesarean: Remove a fibroid only if it obstructs the uterine incision or delivery, or threatens major haemorrhage.
- Plan postpartum follow-up: Expect fibroids to shrink after delivery, review bleeding, and offer long-term options if symptoms persist.
Where the exam tries to catch you
Examiners test whether you know when fibroids need action in pregnancy and when they should be left alone.
- Trap: Perform a routine myomectomy at every caesarean for a fibroid. Correct: Routine removal increases bleeding without clear benefit, so myomectomy is reserved for fibroids that obstruct delivery or threaten haemorrhage.
- Trap: Attribute sudden pain in a fibroid pregnancy to placental abruption. Correct: Red degeneration causes focal pain with fever and preserved fetal wellbeing, whereas abruption brings bleeding and fetal distress.
- Trap: Operate on red degeneration during pregnancy. Correct: Conservative management is the standard, because surgery during pregnancy carries higher risk than symptomatic care.
- Trap: Expect any large fibroid to obstruct labour. Correct: Obstruction is typical for lower-segment or cervical fibroids, whereas fundal fibroids rarely obstruct labour, so the site decides the route.
Frequently asked questions
Does a fibroid in pregnancy usually need surgery?
A fibroid in pregnancy usually needs no surgery, because most cause no harm and many shrink after delivery. Surgery is reserved for obstruction, uncontrolled bleeding or suspicion of malignancy in a fibroid in pregnancy.
What causes pain in red degeneration of a fibroid during pregnancy?
Red degeneration causes pain through haemorrhagic infarction within the fibroid, usually in the second trimester. The pain is focal with tenderness and sometimes fever, and conservative care with analgesia and rest usually settles it.
Which fibroid location causes obstructed labour?
Lower-segment and cervical fibroids cause obstructed labour by blocking the birth canal. A fibroid in this position usually leads to an elective caesarean section planned near term.
When is myomectomy performed at caesarean section?
Myomectomy at caesarean section is performed when an accessible fibroid obstructs delivery or threatens significant haemorrhage. Routine removal of fibroids at caesarean is not recommended, because it adds bleeding without clear benefit.