Surveillance of triplets with umbilical artery velocimetry waveforms.

Doppler arterial velocimetry waveforms was used as a method of antenatal surveillance for triplets. Six sets of triplet pregnancies were studied. Each fetus was identified by real-time-ultrasound scanning and the peak systolic/end diastolic (S/D) ratio was calculated. In one set of triplets two fetuses showed absent end diastolic flow. Both subsequently suffered from necrotising enterocolitis and had major bowel resection. The five other sets of triplets maintained a normal S/D ratio. Three had a normal outcome and two delivered prematurely.