We sought to investigate outcomes of contemporaneously managed monochorionic diamniotic (MCDA) twins, stratified by pregnancy complication.
Four hundred eighteen MCDA pregnancies from 2001 through 2008 were retrospectively reviewed.
There were 236 ongoing pregnancies at 24weeks' gestation. The likelihood of progressing from 24weeks to 2 live births was 98.7% in uncomplicated pregnancies, 89.7% with twin-twin transfusion syndrome, and 100% with growth discordance, increasing at 32weeks to 99.5%, 93.8%, and 100%, respectively. The relative risk (RR) of birth <32weeks was significantly greater in twin-twin transfusion syndrome (RR, 4.1; 95% confidence interval, 2.7–6.1) and growth discordant (RR, 2.1; 95% confidence interval, 1.8–3.8) pregnancies than in uncomplicated pregnancies (P<.0001).
This represents one of the largest cohorts of MCDA twins. The risk of third-trimester fetal loss was low. The likelihood of both intrauterine fetal demise and preterm birth were greater in complicated pregnancies. In the absence of a clinical indication for delivery, these data do not support elective preterm delivery for prevention of intrauterine fetal demise in uncomplicated MCDA twins