Computerised interpretation of fetal heart rate during labour (INFANT): a randomised controlled trial

Abstract

Background: Continuous electronic fetal heart-rate monitoring is widely used during labour, and computerised interpretation could increase its usefulness. We aimed to establish whether the addition of decision-support software to assist in the interpretation of cardiotocographs affected the number of poor neonatal outcomes.

Methods: In this unmasked randomised controlled trial, we recruited women in labour aged 16 years or older having continuous electronic fetal monitoring, with a singleton or twin pregnancy, and at 35 weeks' gestation or more at 24 maternity units in the UK and Ireland. They were randomly assigned (1:1) to decision support with the INFANT system or no decision support via a computer-generated stratified block randomisation schedule. The primary outcomes were poor neonatal outcome (intrapartum stillbirth or early neonatal death excluding lethal congenital anomalies, or neonatal encephalopathy, admission to the neonatal unit within 24 h for ≥48 h with evidence of feeding difficulties, respiratory illness, or encephalopathy with evidence of compromise at birth), and developmental assessment at age 2 years in a subset of surviving children. Analyses were done by intention to treat. This trial is completed and is registered with the ISRCTN Registry, number 98680152.

Findings: Between Jan 6, 2010, and Aug 31, 2013, 47 062 women were randomly assigned (23 515 in the decision-support group and 23 547 in the no-decision-support group) and 46 042 were analysed (22 987 in the decision-support group and 23 055 in the no-decision-support group). We noted no difference in the incidence of poor neonatal outcome between the groups-172 (0·7%) babies in the decision-support group compared with 171 (0·7%) babies in the no-decision-support group (adjusted risk ratio 1·01, 95% CI 0·82-1·25). At 2 years, no significant differences were noted in terms of developmental assessment.

Interpretation: Use of computerised interpretation of cardiotocographs in women who have continuous electronic fetal monitoring in labour does not improve clinical outcomes for mothers or babies.

Funding: National Institute for Health Research.

Figure

Trial profile The 46 042 women included in the analysis includes 448 women with two singleton birth episodes and six women with one singleton and one twin birth episode in the study period. The allocation received for the subsequent delivery was independent of the first allocation received. 30 of 21 509† infants in the decision-support group and 37 of 21 599† infants in the no-decision-support group died before 24 months. Parent Report of Children's Abilities—Revised (PARCA-R). *One woman who withdrew (with consent to use of data) was also randomly assigned in error. †Data from the Ireland not included in the numerator (n=1 decision support) or denominator (n=1754 in decision support and n=1752 in no decision support) because data for deaths after discharge were not available; deaths in the flow chart include stillbirths (n=1 in decision support and n=2 in no decision support).