Antenatal interventions to reduce preterm birth: an overview of Cochrane systematic reviews

Abstract

BackgroundSeveral factors are associated with an increased risk of preterm birth (PTB); therefore, various interventions might have the potential to influence it. Due to the large number of interventions that address PTB, the objective of this overview is to summarise evidence from Cochrane reviews regarding the effects and safety of these different interventions.MethodsWe conducted a systematic literature search in the Cochrane Database of Systematic Reviews. Included reviews should be based on randomised controlled trials comparing antenatal non-pharmacological and pharmacological interventions that directly or indirectly address PTB with placebo/no treatment or routine care in pregnant women at less than 37 completed weeks of gestation without signs of threatened preterm labour. We considered PTB at less than 37 completed weeks of gestation as the primary outcome.ResultsWe included 56 Cochrane systematic reviews. Three interventions increased PTB risk significantly. Twelve interventions led to a statistically significant lower incidence of PTBs. However, this reduction was mostly observed in defined at-risk subgroups of pregnant women. The remaining antenatal interventions failed to prove a significant effect on PTB < 37 weeks, but some of them at least showed a positive effect in secondary outcomes (e.g., reduction in early PTBs). As an unintended result of this review, we identified 28 additional Cochrane reviews which intended to report on PTB < 37 weeks, but were not able to find any RCTs reporting appropriate data.ConclusionsThe possible effects of a diverse range of interventions on PTB have been evaluated in Cochrane systematic reviews. Few interventions have been demonstrated to be effective and a small number have been found to be harmful. For around half of the interventions evaluated, the Cochrane review concluded that there was insufficient evidence to provide sound recommendations for clinical practice. No RCT evidence is available for a number of potentially relevant interventions.

Effects of nutrition interventions during pregnancy on low birth weight: an overview of systematic reviews

“…43 A previous overview review focused on antenatal interventions to prevent PTB. 15 Our results are consistent with this review with two exceptions. Piso et al found that vitamin C supplementation during pregnancy increased the risk of PTB and magnesium supplementation decreased the risk of PTB, LBW and SGA.…”

“…As antenatal interventions to reduce PTB were recently reviewed, we did not include reviews that focused only on PTB. 15 Nutrition-specific and nutrition-sensitive interventions periconceptionally and/or during pregnancy were considered for inclusion. We included reviews where participants were women with a singleton pregnancy despite any potential risk of LBW.…”

Energy and protein intake during pregnancy in relation to preterm birth: A Case Control Study

“…There seems to be an upward trend [2,3], which contributes to almost 3.6 million preterm births accounting for 23.6% of the global preterm births reported each year [4]. Preterm birth has been consistently associated with maternal underweight and nutrient deficiencies during pregnancy [5][6][7][8][9].…”

Prediction and Diagnosis of Preterm Delivery: Review

“…7 Bir baş-kasında, 20-37. haftalar arasında doğum ağrılarının hissedilmesi, kontraksiyonların saptanması (4/20 dk veya 6/60 dk), membran rüptürü veya >20 mm servikal açıklık, %80'in üzerinde servikal silinme veya membranların intakt olmakla birlikte süreç içinde servikal açılma veya silinmenin artması kriterler arasındadır. 8 Preterm eylem tehdidi, servikal değişikliklerin eşlik etmediği kontraksiyonların saptanması durumudur. 9 Servikal uzunluk ölçümü için en güvenilir yöntem, TVUSG'dir.…”