Significant effects on neonatal morbidity and mortality after regional change in management of post-term pregnancy

Objective. To evaluate the effects on neonatal morbidity of a regional change in induction policy for post‐term pregnancy from 43+0 to 42+0 gestational weeks (GWs). Design and setting. Nationwide retrospective register study between 2000 and 2007. Population. All singleton pregnancies with a gestational age of >41+2 GW (n= 119,198). Methods. All Swedish counties were divided into three groups where study group allocation was designated by the proportion of pregnancies >42+2 GW among all pregnancies of >41+2 GW. Stockholm county formed a separate group. Main outcome measures. Perinatal morbidity. Results. In counties with the most active management, 19% of pregnancies >41+2 GW were delivered at >42+2 GW during 2000–2004 compared to 7.1% in 2005–2007. In the least active counties, corresponding figures were 21.0% compared to 19.4%. During 2005–2007, the odds ratios for meconium aspiration and 5‐minute Apgar score of ≤6 in the least compared to most active counties, were 1.55 (95% CI: 1.03–2.33) and 1.26 (95% CI: 1.06–1.51). In Stockholm >42+2GW seen among pregnancies of >41+2 decreased from 21.0% in 2000–2004 to 5.9% in 2005–2007. Reduced perinatal death risks by 48%, meconium aspiration of 51% and low Apgar scores by 31% in 2005–2007 compared with 2000–2004 were observed. Rates of operative deliveries at >41+2 GW in Stockholm were unaltered. Conclusion. A significant reduction in perinatal morbidity was found, with no influence on operative delivery rates for post‐term pregnancy in Stockholm. We advocate a nationwide change toward more active management of post‐term pregnancies.