Spontaneous sIUFDs
For spontaneous sIUFDs (n=22), the median gestation at first sIUFD was 24 weeks (IQR: 11 weeks) with the latest gestation a sIUFD was diagnosed at 36 weeks (Table 2).
Surviving co-twin outcomes
Figure 1 summarises the outcomes.The outcome data for the surviving co-twin was missing in 11/81 cases (14%). 8 of the 11 cases were reported by a Fetal Medicine Centre who had treated complications, but the referring hospital where they received their ongoing maternity care did not provide outcome data, thus the data presented are the outcomes of 70 surviving co-twins. The perinatal death rate of the co-twin was 14% (10/70): there were 8 prenatal deaths and 2 neonatal deaths, equating to 62/70 livebirths (88.6%). The surviving co-twin miscarried in 3 pregnancies. There were 2 stillbirths both following FLA for TTTS in the second trimester. There were no intrapartum stillbirths. Three pregnancies with TTTS had further complications of the condition resulting in a decision for selective termination of pregnancy (e.g. abnormal CNS imaging, severe IUGR). There were 2 neonatal deaths due to extreme prematurity following fetal therapy.