Stillbirths preceded by reduced fetal movements are more frequently associated with placental insufficiency: a retrospective cohort study.

Objectives: Maternal report of reduced fetal movements (RFM) is a means of identifying fetal compromise in pregnancy. In live births RFM is associated with altered placental structure and function. Here, we explored associations between RFM, pregnancy characteristics, and the presence of placental abnormalities and fetal growth restriction (FGR) in cases of stillbirth.

Methods: A retrospective cohort study was carried out in a single UK tertiary maternity unit. Cases were divided into three groups: 109 women reporting RFM, 33 women with absent fetal movements (AFM) and 159 who did not report RFM before the diagnosis of stillbirth. Univariate and multivariate logistic regression was used to determine associations between RFM/AFM, pregnancy characteristics, placental insufficiency and the classification of the stillbirth.

Results: AFM or RFM were reported prior to diagnosis of stillbirth in 142 (47.2%) of cases. Pregnancies with RFM prior to diagnosis of stillbirth were independently associated with placental insufficiency (Odds Ratio (OR) 2.79, 95% Confidence Interval (CI) 1.84, 5.04) and were less frequently associated with maternal proteinuria (OR 0.16, 95% CI 0.07, 0.62) and previous pregnancy loss <24 weeks (OR 0.20, 95% CI 0.07, 0.70). When combined, AFM and RFM were less frequently reported in twin pregnancies ending in stillbirth and in intrapartum stillbirths.

Conclusions: The association between RFM and placental insufficiency was confirmed in cases of stillbirth. This provides further evidence that RFM is a symptom of placental insufficiency. Therefore, investigation after RFM should aim to identify placental dysfunction.