Umbilical artery Doppler Velocimetry: A valuable tool for antenatal fetal surveillance?

Objective: To determine umbilical artery Doppler velocity parameter systolic: diastolic ratio (S/D ratio) relation with fetal well being and outcome. Setting: Department of Obstetrics and Gynecology, Lady Willingdon Hospital, Lahore Duration of study: Six months from 27-02-2008 to 26-08-2008. Subjects and methods: Sixty patients fulfilling the inclusion criteria were included in this study. They were subdivided into two groups. Group 'A' included 30 normal pregnant women with no medical or obstetrical risk factors and group 'B' included 30 pregnant women having risk factors like, hypertension, diabetes, Rhesus incompatibility, discordant twins, intrauterine growth restriction and non immunehydropsfetalis. Results: In comparison of S/D ratio with risk factors it was observed that S/D ratio <= 3 was present in 7 patients (11.6%) with hypertension/preeclampsia, 2 patients (3.3%) with diabetes, 1 patient (1.6%) with intrauterine growth restriction, 9 patients (15.0%) with oligohydramnios, no patient with twin pregnancy while S/D ratio >3 was present in 19 patients (31.6%) in pregnancy with hypertension/preeclampsia, 3 patients (5%) with diabetes mellitus, 11 patients (18.3%) with intrauterine growth restriction, 15 patients (25.0%) with oligohydramnios and only 1 patient (1.6%) with twin pregnancy. It was observed that women with S/D ratio <= 3, no neonate was observed with < 4 Apgar at 1 minute. 5 neonates (8.3%) had <= 6 Apgar score at five minute, 10 neonates (16.6%) needed resuscitation and 7 neonates (11.6%) were admitted to neonatal unit. On the other hand women with >3 S/D ratio delivered 10 neonates (16.6%) with <4 Apgar score at 1 minute, 23 (38.3%) with <= 6 score at 5 minutes and 23 neonates (38.3%) needed resuscitation, 21 (35.0%) were admitted to neonatal unit for asphyxia. Conclusion: Umbilical artery Doppler studies is an integral tool while evaluating health of high risk pregnancies. However, it is not appropriate as a screening tool for low risk pregnancies.