Regimens of fetal surveillance for impaired fetal growth.

BACKGROUND: Policies and protocols for fetal surveillance in the pregnancy where impaired fetal growth is suspected vary widely, with numerous combinations of different surveillance methods.

OBJECTIVES: To assess the effects of antenatal fetal surveillance regimens on important perinatal and maternal outcomes.

SEARCH STRATEGY: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (April 2008).

SELECTION CRITERIA: Randomised and quasi-randomised trials comparing the effects of described antenatal fetal surveillance regimens.

DATA COLLECTION AND ANALYSIS: R Grivell and L Wong independently assessed trial eligibility and quality and extracted data.

MAIN RESULTS: One trial of 167 women and their babies was included. This trial was a pilot study recruiting alongside another study, therefore a separate sample size was not calculated. The trial compared a twice-weekly surveillance regimen (biophysical profile, nonstress tests, umbilical artery and middle cerebral artery Doppler and uterine artery Doppler) with the same regimen applied fortnightly (both groups had growth assessed fortnightly). There were insufficient data to assess this review's primary infant outcome of composite perinatal mortality and serious morbidity (although there were no perinatal deaths) and no difference was seen in the primary maternal outcome of emergency caesarean section for fetal distress. In keeping with the more frequent monitoring, mean gestational age at birth was four days less for the twice-weekly surveillance group compared with the fortnightly surveillance group. Women in the twice-weekly surveillance group were 25% more likely to have induction of labour than those in the fortnightly surveillance group. The risk ratio was 1.25 (95% confidence interval 1.04 to 1.50).

AUTHORS' CONCLUSIONS: There is limited evidence from randomised controlled trials to inform best practice for fetal surveillance. regimens when caring for women with pregnancies affected by impaired fetal growth. More studies are needed to evaluate the effects of currently used fetal surveillance regimens in impaired fetal growth.