Bicornuate uterus and other uterine differences in pregnancy
A uterus that formed in a different shape. Some of these differences matter for pregnancy, some do not, and one of them is straightforwardly treatable.
The differences, and which matter
The uterus forms from two tubes that fuse. When fusion is incomplete, the result can be a septate uterus (a wall of tissue dividing the cavity), a bicornuate uterus (heart-shaped, with two horns), a unicornuate uterus (one half developed), or a didelphys (two separate cavities).
A septate uterus is the one most associated with miscarriage — and it is the one that is surgically correctable, by hysteroscopic removal of the septum. Outcomes after that surgery are generally good.
A bicornuate uterus is associated with somewhat higher rates of preterm birth, breech presentation and caesarean, and with a smaller increase in miscarriage risk. Surgery is rarely done for it.
Many women with a uterine difference have entirely normal pregnancies and never know until a scan finds it incidentally.
Diagnosis and care
Often found on ultrasound, and confirmed with a 3D ultrasound, MRI or hysteroscopy — the distinction between septate and bicornuate matters because the treatment differs, and ordinary 2D ultrasound cannot always tell them apart.
In pregnancy, expect: closer monitoring, growth scans, attention to the baby's position (breech is commoner), and cervical length monitoring where indicated.
Kidneys are also checked in some cases, because urinary tract differences sometimes accompany uterine ones.
Ask your obstetrician the specific version: which difference do I have, has it been confirmed properly, does it need treatment, and what does it mean for delivery.
When to see a doctor
Go to hospital immediately for: bleeding that soaks a pad an hour or more, severe or one-sided abdominal pain, dizziness or fainting, shoulder-tip pain, fever with chills, or foul-smelling discharge. A positive pregnancy test with one-sided pain and bleeding needs assessment the same hour — an ectopic pregnancy is life-threatening. Call 108 if you cannot travel quickly.
In pregnancy with a known uterine difference: bleeding, pelvic pressure, a change in discharge, regular tightening before 37 weeks, severe pain, or reduced fetal movements are all same-day.
Before conceiving: ask for a proper assessment if you have had two or more losses, a second-trimester loss, or a previous preterm birth — a correctable septum is worth finding.
Grief after a pregnancy loss is real grief, at any number of weeks. If you are struggling — persistent low mood, hopelessness, panic, an inability to function, or any thought of harming yourself — that deserves help rather than endurance. Tele-MANAS on 14416 is free, confidential and answers round the clock in Indian languages.
This article is general information, not medical advice, and is no substitute for personal medical advice. For any decision about your or your child's health, please consult your doctor.
Frequently asked questions
Can I have a normal pregnancy?
Many women do. The risks are modestly higher for preterm birth and breech position, and monitoring addresses both.
Should I have surgery?
For a septum with a history of loss, often yes. For a bicornuate uterus, usually not. It depends on which difference you have, which is why accurate diagnosis matters.
Will I need a caesarean?
Not automatically. It is more likely, largely because breech presentation is commoner, and the decision is made in late pregnancy.
Does it affect fertility?
Conception is usually not the problem; the association is mainly with miscarriage and preterm birth. Difficulty conceiving deserves its own investigation.
Sources
Every clinical figure on this page is taken from the guidelines below. Where our numbers and your doctor's differ, ask which guideline they follow.
- NICE. Ectopic Pregnancy and Miscarriage: Diagnosis and Initial Management (NICE Guideline NG126) (2021)Supports the urgent-assessment advice for a positive pregnancy test with one-sided pain and bleeding, and the characterisation of ectopic pregnancy as life-threatening requiring same-hour assessment.
- NICE. Preterm Labour and Birth (NICE Guideline NG25) (2022)Backs the recommendation for cervical length monitoring in pregnancies at higher risk of preterm birth (including uterine anomalies), and the advice to seek same-day assessment for regular tightenings before 37 weeks.
- WHO. WHO Recommendations on Antenatal Care for a Positive Pregnancy Experience (2016)Supports the general framework of closer monitoring and growth scans in higher-risk pregnancies, and the recommendation that fetal position and fetal movements are assessed in antenatal care.
- ACOG. Practice Bulletin No. 200: Early Pregnancy Loss (2018)Supports the claim that septate uterus is the uterine anomaly most strongly associated with miscarriage and that hysteroscopic resection of the septum is associated with improved subsequent pregnancy outcomes.
Reviewed by
- Nakul Phatak — CEO, theAsianparent India & IndonesiaHead of theAsianparent India; father of one
- Roshni Chugani — Head of Marketing, theAsianparent India & Singapore12 years in the mother-and-baby space; mother of two
Published by: theAsianparent editorial team
