Decline in stillbirths and perinatal mortality after implementation of a more aggressive induction policy in post-date pregnancies: a nationwide register study

摘要

Introduction. In 2011 Danish national guidelines were changed towards a more aggressive induction and fetal surveillance policy from (1) induction of labor at gestational age (GA) of 42(+0) weeks and (2) no fetal surveillance after 40(+0) weeks to (1) induction of labor between 41(+2) and 41(+6) weeks, (2) earlier induction at 41(+0) weeks in the case of maternal age >40 years or body mass index (BMI) >35 kg/m(2) and (3) fetal surveillance at GA 41(+0) weeks. Material and methods. This national cohort study included all pregnancies that reached 41(+0) weeks of gestation in 2008-2014 (n = 102 167). Multivariate logistic regression analyses were used to estimate risks in the years after (2012-2014) vs. before (2008-2010) new national guidelines, adjusted for maternal age, BMI, and parity. Results. We observed a decline in stillbirths from 0.9%(0) to 0.5%(0) [odds ratio (OR) (adjusted) 0.50, 95% CI 0.29-0.89, p = 0.018]. Furthermore, a decline in perinatal deaths from 1.3%(0) to 0.8%(0) (ORadjusted 0.62, 95% CI 0.39-0.96, p = 0.033) and vacuum extraction (ORadjusted 0.86, 95% CI 0.82-0.90, p = 0.007) was observed. The risk of cesarean section (ORadjusted 0.98, 95% CI 0.94-1.02, p = 0.251), Apgar score below 7 at five minutes (ORadjusted 0.96, 95% CI 0.81-1.14, p = 0.0.678) and admissions to the neonatal department (ORadjusted 1.04, 95% CI 1.00-1.14, p = 0.064) did not change, whereas induction of labor increased from 28.2 to 42.6% (ORadjusted 1.89, 95% CI 1.84-1.95, p < 0.001). Conclusions. This study showed a decline in stillbirths and perinatal mortality after implementation of new Danish guidelines for post-date pregnancies. The risk of interventions as cesarean section and vacuum extraction remained stable despite an increase in labor inductions.