Caesarean section
For otherwise healthy twin pregnancies where both twins are head down a trial of vaginal delivery is recommended at between 37 and 38 weeks. Vaginal delivery in this case does not worsen the outcome for the infant as compared with Caesarean section. There is controversy on the best method of delivery where the first twin is head first and the second is not. When the first twin is not head down a caesarean section is often recommended. It is estimated that 75% of twin pregnancies in the United States were delivered by caesarean section in 2008. In comparison, the rate of caesarean section for all pregnancies in the general population varies between 14% and 40%. In twins that share the same placenta, delivery may be considered at 36 weeks. For twins who are born early, there is insufficient evidence for or against placing preterm stable twins in the same cot or incubator (co-bedding).