Monochorionic twin pregnancies are high-risk and closely monitored antenatally. A systematic review revealed no existing predictive factors for twin-twin transfusion syndrome (TTTS), growth restriction, or intrauterine fetal death (IUFD). The Optimal Management of Monochorionic Twins (OMMIT) study found that first trimester inter-twin nuchal translucency discordance, crown-rump length discordance, β-hCG, PAPP-A, AFP, PlGF and sFlt-1 do not predict adverse outcome.
A difference was seen in novel second trimester biomarkers: in the recipient twin amniotic fluid metabolites pre- and post-fetoscopic laser ablation; and a relationship with recipient twin cardiac function was demonstrated. Discovery work on miRNA in second trimester maternal serum of TTTS pregnancies found no difference compared to uncomplicated monochorionic twin pregnancies.
A systematic review provided a more personalised risk prediction for the surviving co-twin in single IUFD, including that that the rate of abnormal brain imaging is 20% and the IUFDs occurring at 14-28 weeks are at higher risk.
A preliminary study of parent-fetal antenatal and postnatal attachment and depression in TTTS pregnancies found maternal attachment increased postnatally and depressive symptoms decreased, whereas paternal scores did not change. This thesis has reported exciting findings which have clinical implications, and advance knowledge of complicated monochorionic twin pregnancies
