Uterine Didelphys

Uterus didelphys is a complete duplication of the uterus, with two separate uterine corpora, two cervices, and often a longitudinal vaginal septum, caused by complete failure of fusion of the Müllerian ducts. It makes up about 5 to 8 percent of Müllerian anomalies.

Each uterus is a hemi uterus connected to its own fallopian tube and ovary.

It is the most common anomaly with an obstructing vaginal septum, and when one hemivagina is blocked, it forms OHVIRA syndrome (obstructed hemivagina with ipsilateral renal agenesis, which is present in about 80 to 90 percent of such cases).

• Most women are asymptomatic and have a normal menstrual cycle; many are diagnosed at first intercourse (dyspareunia because of a vaginal septum), during pregnancy, or by imaging.
• Failure of tampon use to control the bleeding (because the second vagina bleeds).
• OHVIRA: pelvic pain and progressive dysmenorrhoea after menarche, a paravaginal or lower abdominal mass, foul discharge (pyocolpos), and fever.
• Obstetric: pregnancy is possible in either uterus (and rarely both, as dizygotic twins).
  • The miscarriage rate is about 20 to 30 percent, preterm delivery 20 to 45 percent, growth restriction 15 to 25 percent, breech presentation about 40 to 50 percent, and caesarean section 80 percent.
  • Live birth rate is 60 to 70 percent.
  • Pregnancy in the non-obstructed side is not hindered, and the non-pregnant uterus may enlarge and obstruct labour (less common).
• Associated renal agenesis (on the side of the obstruction) and other anomalies.

• Pelvic examination: two cervices on speculum examination (may be missed if only one is seen).
• Three dimensional ultrasound and MRI: two separate uterine bodies with a wide divergence and a deep cleft between them, two cervices, and the vaginal septum; MRI delineates obstruction and endometriosis.
• Renal ultrasound to search for renal agenesis or ectopic ureters.
• Hysterosalpingography shows two separate hemicavities and cervices (must cannulate both).

• Asymptomatic didelphys without obstruction needs no surgery. Unification surgery (Strassman) is not recommended because outcomes of pregnancy are acceptable, and surgery may reduce fertility.
• Longitudinal vaginal septum causing dyspareunia or planned for obstruction of labour: resect via the vaginal approach, preserving both cervices. Septum resection in the lithotomy position with clamping and division of the septum and oversewing of the edges using 3-0 polyglactin.
• OHVIRA: vaginal septum resection (marsupialisation) at the point of maximal bulge with drainage of the haematocolpos. Do not remove the obstructed uterus. Antibiotics if infection (co-amoxiclav 625 mg every 8 hours for 5 to 7 days). Pain is relieved immediately and fertility outcomes are excellent. Laparoscopy is added in persistent pain for endometriosis.
• Antenatal care:
  • Early ultrasound confirmation of the pregnancy location (and the location relative to the second uterus).
  • Cervical length monitoring every 2 weeks from 16 to 24 weeks.
  • Cerclage for cervical insufficiency or a short cervix.
  • Vaginal progesterone 200 mg nightly if the cervix is below 25 mm.
  • Growth scans every 4 weeks from 28 weeks, and fetal presentation assessment at 36 weeks.
• Delivery: vaginal birth in cephalic presentation; caesarean section for breech (common), transverse lie, and other obstetric indications. At caesarean, the non-pregnant uterus is left intact.
• Postpartum haemorrhage risk is higher: active management of the third stage with oxytocin 10 units intramuscularly, and tranexamic acid 1 g intravenously ready.
• Contraception: an intrauterine device in one uterus does not protect the other, so a hormonal method is used.