Can information regarding the index stillbirth determine risk of adverse outcome in a subsequent pregnancy? Findings from a single‐center cohort study

Abstract

Introduction Women with a history of stillbirth have an almost five‐fold increased risk of stillbirth in a subsequent pregnancy, as well as increased risk of other adverse maternal and neonatal outcomes. The reasons for this association are not well understood but could relate to recurrent causes. We aimed to determine whether information from the time of index stillbirth, including cause, is associated with outcome of a subsequent pregnancy. Material and methods A retrospective cohort study was conducted at a UK tertiary maternity center. Cases were included if stillbirth was investigated, subsequent pregnancy care was provided, and the birth occurred in the same unit. Data on maternal characteristics, findings of investigations, and classification of death using the ReCoDe system were extracted, and logistic regression was performed to determine whether these factors were associated with adverse outcome in the subsequent pregnancy. Results In this cohort (n = 266), there were 69 adverse outcomes, including three perinatal deaths. Preterm delivery (16.2%) and birthweight <10th centile (12.4%) were the most common adverse outcomes. Of the preterm births, 69.8% were iatrogenic and 47% of these were due to abnormalities of fetal growth. On multivariate analysis women with a preexisting medical condition (adjusted odds ratio [aOR] 2.12, 95% CI 1.10‐4.12) and those who smoked in their subsequent pregnancy (aOR 6.80, 95% CI 1.99‐23.30) were at increased risk of adverse outcome. Neither ReCoDe classification of stillbirth (P = .61) nor gestation of stillbirth (P = .36) were associated with subsequent pregnancy outcome. Placental histopathological findings of maternal vascular malperfusion (aOR 11.34, 95% CI 2.20‐58.62), fetal vascular malperfusion (aOR 9.27, 95% CI 1.09‐78.82), and chorioamnionitis (aOR 6.35, 95% CI 1.16‐34.78) in the index stillbirth were associated with adverse outcome in subsequent pregnancy. These associations were independent of maternal characteristics. Conclusions Placental examination at time of stillbirth is important, as certain placental disorders inform the risk of adverse outcome in subsequent pregnancy. In this cohort, information regarding maternal characteristics and classification of cause of stillbirth do not provide significant prognostic information about the risk of adverse outcome in subsequent pregnancies. Optimal management of maternal medical disorders and access to smoking cessation are essential.

Risk of stillbirth and adverse pregnancy outcomes in a third pregnancy when an earlier pregnancy has ended in stillbirth

“…Women who had preexisting medical conditions (aOR 2.12, 95% CI 1.10-4.12) and who continued to smoke cigarettes had an increased risk of adverse outcomes (aOR 6.80, 95% CI 1.99-23.30), as did women whose placental histopathological examination after stillbirth showed evidence of fetal vascular malperfusion, maternal vascular malperfusion and chorioamnionitis. 19 We were able to adjust for some of these factors, for example, maternal preexisting medical conditions, TA B L E 5 Sensitivity analysis of the association between history of stillbirth and the risk of adverse pregnancy outcomes in the third pregnancy restricted to birth records after July 2008. b Data were missing for 101 records, and these records were therefore excluded from this analysis.…”

“…studied 266 women who had a prior stillbirth or perinatal death, 69 (26%) of whom had an adverse outcomes, including: 3 perinatal deaths, 43 (16.2%) preterm births and 32 SGA infants (12.4%). Women who had preexisting medical conditions (aOR 2.12, 95% CI 1.10–4.12) and who continued to smoke cigarettes had an increased risk of adverse outcomes (aOR 6.80, 95% CI 1.99–23.30), as did women whose placental histopathological examination after stillbirth showed evidence of fetal vascular malperfusion, maternal vascular malperfusion and chorioamnionitis 19 . We were able to adjust for some of these factors, for example, maternal preexisting medical conditions, smoking and BMI in our analysis, which suggests that the increased risk of stillbirth is not solely mediated by the presence of maternal disease and demographic factors.…”

Pregnancy Outcomes Subsequent to Stillbirth—A Single Tertiary-Care Center Experience

“…The tendency for these conditions to recur suggests common pathogenetic factors related to impaired placental function [16,24,51,52]. Screening methods to identify placental disorders during pregnancy and specific interventions may help preventing stillbirth [47].…”

Risk of Recurrent Stillbirth in Subsequent Pregnancies

“…The tendency for preterm birth, preeclampsia, placental abruption, and fetal growth restriction to recur suggests common causal factors for stillbirth related to impaired placental function, 5,[23][24][25][26] and the possibility that these conditions predispose to each other. 27 Lean and colleagues 28,29 provide evidence for a link between advanced maternal age and placental dysfunction.…”