Impact of obstetric interventions on condition at birth in extremely preterm babies: evidence from a national cohort study

Abstract

BackgroundTo investigate perinatal decision-making and the use of obstetric interventions, we examined the effects of antenatal steroids, tocolysis, and delivery mode on birth in a good condition (defined as presence of an infant heart rate >100 at five minutes of age) and delivery-room (DR) death in extremely preterm deliveries.MethodsProspective cohort of all singleton births in England in 2006 at 22–26 weeks of gestation where the fetus was alive at the start of labour monitoring or decision to perform caesarean section. Odds ratios adjusted for potential confounders (aOR) were calculated using logistic regression.ResultsOne thousand seven hundred twenty two singleton pregnancies were included. 1231 women received antenatal steroids, 437 tocolysis and 356 delivered by Caesarean section. In babies born vaginally, aOR between a partial course of steroids and improved condition at birth was 1.84, 95% CI: 1.20 to 2.82 and, for a complete course, 1.63, 95% CI: 1.08 to 2.47; for DR death, aORs were 0.34 (0.21 to 0.55) and 0.41 (0.26 to 0.64) for partial and complete courses of steroids. No association was seen for steroid use in babies delivered by Caesarean section. Tocolysis was associated with improved condition at birth (aOR 1.45, 95% CI: 1.05 to 2.0) and lower odds of death (aOR 0.48, 95% CI: 0.32 to 0.73). In women without spontaneous labour, Caesarean delivery at ≤24 and 25 weeks was associated with improved condition at birth ((aORs 12.67 (2.79 to 57.60) and 4.94 (1.44 to 16.90), respectively) and lower odds of DR death (aORs 0.03 (0.01 to 0.21) and 0.13 (0.03 to 0.55)). There were no differences at 26 weeks gestation or in women with spontaneous labour.ConclusionsAntenatal steroids are strongly associated with improved outcomes in babies born vaginally. Tocolysis was associated with improvements in all analyses. Effects persisted after adjustment for perinatal decision-making. However, associations between delivery mode and birth outcomes may be attributable to case selection.Electronic supplementary materialThe online version of this article (doi:10.1186/s12884-016-1154-y) contains supplementary material, which is available to authorized users.

Intensity of perinatal care, extreme prematurity and sensorimotor outcome at 2 years corrected age: evidence from the EPIPAGE-2 cohort study

“…This is the same method and the same population as previously used by investigators in the EXPRESS study [ 14 ]. In that study, they used rates of obstetric treatments such as administration of antenatal steroids, tocolysis and caesarean section—all of which are strongly linked to improved survival prior to neonatal unit admission [ 34 ]—as contributory factors towards their ‘regional activity score’. The EXPRESS investigators additionally performed analyses in the live-born population, as did we.…”

Maternal and infant morbidity following birth before 27 weeks of gestation: a single centre study

“…This may prevent some of the unpredictable complications of a labour but must be balanced against the added morbidity to the mother. Current evidence suggests that delivery method should be based on obstetric or maternal indications rather than perceived outcome for the baby and Caesarean delivery cannot be recommended routinely 6 , 23 – 26 , although it may reduce the occurrence of intraventricular haemorrhage 27 . A pilot feasibility trial (the CASSAVA study) to address the question of mode of delivery at extreme preterm gestations has been funded in the UK (NIHR 17/22 Mode of delivery for preterm infants).…”

“…Data on such maternal outcomes are lacking. Current evidence supports certain treatments—for example, use of antenatal steroids 5 , 6 —but is limited regarding interventions such as tocolysis 7 , 8 , magnesium sulphate prophylaxis 9 , augmentation of labour, fetal monitoring and episiotomy. There is even less information concerning the prevalence and management of complications during labour related to malpresentation 10 , 11 , cord prolapse 12 and head entrapment 11 , 13 or their effect on fetal and maternal outcomes.…”

Birth outcomes between 22 and 26 weeks' gestation in national population‐based cohorts from Sweden, England and France

“…We then performed Cox proportional hazards regression adjusted for baseline maternal and pregnancy factors, multiple birth, infant sex and birth weight. We did not adjust for obstetric interventions, place or mode of delivery as these have been demonstrated 9 , 17 , 18 to be related to perinatal decision‐making and are, therefore, intermediate variables between our exposure, the country of each cohort, and survival and other outcomes. Furthermore, the organisation of perinatal care and use of obstetric interventions, in particular Caesarean delivery, vary greatly across countries for reasons that are unrelated to care of extremely preterm birth.…”