The rationale for fetal surveillance in monochorionic twin pregnancies is timely intervention to prevent the increased fetal/perinatal morbidity and mortality attributed to twin–twin transfusion syndrome and intrauterine growth restriction. We investigated the residual risk of fetal death after viability in otherwise uncomplicated monochorionic diamniotic twin pregnancies. We searched an electronic database of 480 completed monochorionic pregnancies that underwent fortnightly ultrasound surveillance in our tertiary referral fetal medicine service between 1992 and 2004. After excluding pregnancies with twin–twin transfusion syndrome, growth restriction, structural abnormalities, or twin reversed arterial perfusion sequence, and monoamniotic and high-order multiple pregnancies, we identified 151 uncomplicated monochorionic diamniotic twin pregnancies with normal growth, normal liquor volume, and normal Doppler studies on fortnightly ultrasound scans. Ten unexpected intrauterine deaths occurred in seven (4.6%) of 151 previously uncomplicated monochorionic diamniotic pregnancies, within 2 wk of a normal scan, at a median gestational age of 34+1 wk (weeks+days; range 28+0 to 36+3). Two of the five cases that underwent autopsy had features suggestive of acute late onset twin–twin transfusion syndrome, but no antenatal indicators of transfusional imbalance or growth restriction, either empirically or in a 1:3 gestation-matched case–control comparison. The prospective risk of unexpected antepartum stillbirth after 32 wk was 1/23 monochorionic diamniotic pregnancies (95% confidence interval 1/11 to 1/63). Despite intensive fetal surveillance, structurally normal monochorionic diamniotic twin pregnancies without TTTS or IUGR are complicated by a high rate of unexpected intrauterine death. This prospective risk of fetal death in otherwise uncomplicated monochorionic diamniotic pregnancies after 32 wk of gestation might be obviated by a policy of elective preterm delivery, which now warrants evaluation.
We report our experience with intracardiac administration of potassium chloride as safe and effective method for late termination of pregnancy (TOP) and to document the indications for feticide in a major tertiary unit. During the study period (January 2000 and December 2005), 239 late terminations of pregnancy were performed at a median gestational age of 22+6 weeks (range 20+6 to 36+3 weeks). The most frequent indication was represented by aneuploidy (24.3%), followed by brain abnormalities (17.6%). Maternal indications were responsible for 2.9% of the total number of terminations. No maternal complications occurred and complete asystole was achieved in all cases with a median volume of potassium chloride of 4.7 ml (range 2–10 ml). Potassium chloride injected directly in the left ventricle induces immediate asystole, and it is a safe and effective method of TOP. Interestingly, despite the widespread introduction of aneuploidy screening, chromosomal abnormalities, particularly trisomy 21, still represent the major indication for late TOP.