Twin Pregnancy with Malpresentation

Twin pregnancy with malpresentation is a twin pregnancy in which one or both fetuses are not cephalic (head first), most often breech or transverse. Malpresentation is common in twin pregnancies at term and affects the second twin more often than the first. It matters because the route and technique of birth decide the risk of cord prolapse, locking, and birth trauma.

• Risk factors: preterm gestation, polyhydramnios, uterine anomaly, fibroids, high parity, low lying placenta.
• Presentations of the two twins can change in labour, particularly the second.
• The first twin's presentation decides the route.

Women have a large uterus and fetal parts felt in unusual places, with high fundal head or breech palpable, and uncomfortable kicks under the ribs. Presentation is confirmed by ultrasound.

• Two heads in the pelvis (locked twins) is rare.
• Fetal heart best heard above the umbilicus in breech.
• Differential diagnosis: singleton malpresentation, polyhydramnios, large fibroid, placenta previa, uterine anomaly.
• Complications: cord prolapse, locked twins, birth trauma, prolonged interval between the twins, emergency caesarean section for the second twin, postpartum haemorrhage, neonatal asphyxia.

The approach is ultrasound for presentation, size and placental site at 36 to 37 weeks and again in labour.

• Ultrasound: presentation of each twin, estimated fetal weight of each, liquor volume, placental sites, cervical length.
• Birth plan at 34 to 36 weeks with presentation recorded at each visit.
• Bedside ultrasound on admission in labour to confirm the lie of both twins.
• Cardiotocography of both fetuses.

The principle is vaginal birth when the first twin is cephalic, caesarean section when the first twin is not cephalic, and skilled management of the second twin.

• Supportive: birth in a theatre capable facility with an obstetrician, a midwife or anaesthetist and two neonatal teams; IV access with cross-matched blood; continuous cardiotocography of both twins; epidural analgesia is helpful.
• Pharmacological: oxytocin infusion 20 IU in 1 litre sodium chloride 0.9 percent at 60 mL per hour (about 20 mU/minute) after delivery of the first twin if contractions stop, with amniotomy when the head or breech is engaged; glyceryl trinitrate 400 micrograms sublingual (or 50 to 100 micrograms IV) for uterine relaxation during internal version or breech extraction; terbutaline 0.25 mg subcutaneous once for uterine relaxation; cefazolin 2 g IV before caesarean section; oxytocin 10 IU IM after delivery of the second twin then infusion of 20 IU in 1 litre at 125 mL per hour for 4 hours; carboprost 250 micrograms IM every 15 minutes (maximum 8 doses) for atony, avoided in asthma.
• Procedures: planned vaginal birth if the first twin is cephalic at 37 weeks; planned caesarean section if the first twin is breech or transverse; second twin cephalic: amniotomy with oxytocin; second twin breech: assisted breech delivery or breech extraction by an experienced operator; second twin transverse: external cephalic version or internal podalic version and breech extraction; emergency caesarean section for failed version, cord prolapse or fetal distress.
• Red flags: cord prolapse of the second twin, interlocking twins, bradycardia of either twin, prolonged interval between twins, haemorrhage.
• Follow-up: umbilical cord blood gases from both cords; separate newborn examination and glucose checks; postnatal haemoglobin at 24 hours.