Low umbilical artery vascular flow resistance and fetal outcome

Normogram of umbilical artery Doppler indices in singleton pregnancies in south-western Nigerian women

AIM

To determine the Doppler indices of the umbilical arteries in normal singleton pregnancy with a view to generating local reference ranges.

METHODS

In this prospective, cross-sectional study, 400 pregnant women at 15-39 weeks' gestational age, with estimated fetal weight within the 10th and 90th percentile, no fetal malformation(s), and without any history of maternal medical disease, were recruited. Umbilical arteries were assessed on ultrasound, with the subjects in the supine position. Resistivity index (RI), pulsatility index (PI) and systolic/diastolic (S/D) ratio were recorded and analyzed.

RESULTS

All the umbilical arteries were paired; no single umbilical artery was seen. Mean RI, PI, and S/D ratio declined with gestational age, and decreased from 1.265 to 0.829, from 0.760 to 0.585 and from 4.068 to 2.365, respectively, from 15 to 39 weeks of gestation. With regard to correlation between gestational age and Doppler indices, r = - 0.598 for PI (P < 0.05), - 0.437 for RI (P < 0.05), and - 0.538 for S/D ratio (P < 0.05). Decline in the Doppler indices was progressive with gestational age.

CONCLUSION

A normogram of umbilical artery Doppler indices was constructed, which showed that the indices decreased with gestational age. These normative data could serve as reference ranges for evaluation of the umbilical artery circulation in this locality.

A case of ultrasound-guided prenatal diagnosis of prune belly syndrome in Papua New Guinea--implications for management

BACKGROUND

Prune belly syndrome is a rare congenital malformation of unknown aetiology and is characterised by abnormalities of the urinary tract, a deficiency of abdominal musculature and bilateral cryptorchidism in males. We report a case of prune belly syndrome from Papua New Guinea, which was suspected on pregnancy ultrasound scan and confirmed upon delivery.

CASE PRESENTATION

A 26-year-old married woman, Gravida 3 Para 2, presented to antenatal clinic in Madang, Papua New Guinea, at 21(+5) weeks' gestation by dates. She was well with no past medical or family history of note. She gave consent to participate in a clinical trial on prevention of malaria in pregnancy and underwent repeated ultrasound examinations which revealed a live fetus with persistent megacystis and anhydramnios. Both mother and clinicians agreed on conservative management of the congenital abnormality. The mother spontaneously delivered a male fetus weighing 2010 grams at 34 weeks' gestation with grossly abnormal genitalia including cryptorchidism, penile aplasia and an absent urethral meatus, absent abdominal muscles and hypoplastic lungs. The infant passed away two hours after delivery. This report discusses the implications of prenatal detection of severe congenital abnormalities in PNG.

CONCLUSION

This first, formally reported, case of prune belly syndrome from a resource-limited setting in the Oceania region highlights the importance of identifying and documenting congenital abnormalities. Women undergoing antenatal ultrasound examinations must be carefully counseled on the purpose and the limitations of the scan. The increasing use of obstetric ultrasound in PNG will inevitably result in a rise in prenatal detection of congenital abnormalities. This will need to be met with adequate training, referral mechanisms and better knowledge of women's attitudes and beliefs on birth defects and ultrasound. National medicolegal guidance regarding induced abortion and resuscitation of a fetus with severe congenital abnormalities may be required.