Outcomes of Induction Versus Spontaneous Onset of Labour at 40 and 41 Gw: Findings From A Prospective Database, Sri Lanka

Abstract

\n Objectives\n\nThe World Health Organization recommends induction of labour (IOL) for low risk pregnancy from 41\u2009+\u20090 gestational weeks (GW). Nevertheless, in Sri Lanka IOL at 40 GW is common practice. This study compares maternal/newborn outcomes after IOL versus spontaneous onset of labour (SOL) at 40 GW (IOL40) and 41 GW (IOL41).\nMethods\n\nData were extracted from the routine prospective individual patient database of the Soysa Teaching Hospital for Women, Colombo. IOL and SOL groups were compared using logistic regression.\nResults\n\nOf 13670 deliveries, 2359 (17.4%) were singleton and low risk at 40 or 41 GW. Of these, 456 (19.3%) women underwent IOL40, 318 (13.5%) IOL41, and 1585 (67.2%) SOL. Both IOL40 and IOL41 were associated with an increased risk of any maternal/newborn negative outcomes (OR\u2009=\u20092.21, 95%CI\u2009=\u20091.75–2.77, p\u2009<\u20090.001 and OR\u2009=\u20091.91, 95%CI\u2009=\u20091.47–2.48, p\u2009<\u20090.001 respectively), maternal complications (OR\u2009=\u20092.18, 95%CI\u2009=\u20091.71–2.77, p\u2009<\u20090.001 and OR\u2009=\u20092.34, 95%CI\u2009=\u20091.78–3.07, p\u2009<\u20090.001 respectively) and CS (OR\u2009=\u20092.75, 95%CI\u2009=\u20092.07–3.65, p\u2009<\u20090.001 and OR\u2009=\u20093.01, 95%CI\u2009=\u20092.21–4.12, p\u2009<\u20090.001 respectively). Results did not change in secondary and sensitivity analyses.\nConclusions\n\nBoth IOL groups were associated with higher risk of negative outcomes compared to SOL. Findings, potentially explained by selection bias, local IOL protocols and CS practices, are valuable for Sri Lanka, particularly given contradictory findings from other settings.