Predictors of poor perinatal outcome following maternal perception of reduced fetal movements--a prospective cohort study

Abstract

Background: Maternal perception of reduced fetal movement (RFM) is associated with increased risk of stillbirth and fetal growth restriction (FGR). RFM is thought to represent fetal compensation to conserve energy due to insufficient oxygen and nutrient transfer resulting from placental insufficiency.

Objective: To identify predictors of poor perinatal outcome after maternal perception of reduced fetal movements (RFM).

Design: Prospective cohort study.

Methods: 305 women presenting with RFM after 28 weeks of gestation were recruited. Demographic factors and clinical history were recorded and ultrasound performed to assess fetal biometry, liquor volume and umbilical artery Doppler. A maternal serum sample was obtained for measurement of placentally-derived or modified proteins including: alpha fetoprotein (AFP), human chorionic gonadotrophin (hCG), human placental lactogen (hPL), ischaemia-modified albumin (IMA), pregnancy associated plasma protein A (PAPP-A) and progesterone. Factors related to poor perinatal outcome were determined by logistic regression.

Results: 22.1% of pregnancies ended in a poor perinatal outcome after RFM. The most common complication was small-for-gestational age infants. Pregnancy outcome after maternal perception of RFM was related to amount of fetal activity while being monitored, abnormal fetal heart rate trace, diastolic blood pressure, estimated fetal weight, liquor volume, serum hCG and hPL. Following multiple logistic regression abnormal fetal heart rate trace (Odds ratio 7.08, 95% Confidence Interval 1.31-38.18), (OR) diastolic blood pressure (OR 1.04 (95% CI 1.01-1.09), estimated fetal weight centile (OR 0.95, 95% CI 0.94-0.97) and log maternal serum hPL (OR 0.13, 95% CI 0.02-0.99) were independently related to pregnancy outcome. hPL was related to placental mass.

Conclusion: Poor perinatal outcome after maternal perception of RFM is closely related to factors which are connected to placental dysfunction. Novel tests of placental function and associated fetal response may provide improved means to detect fetuses at greatest risk of poor perinatal outcome after RFM.

Figure 1. Flow diagram describing recruitment and progress of participants to the cohort study.

Figure 2. Placentally-derived or modified factors measured in maternal serum.

A) human chorionic gonadotrophin (hCG), B) human placental lactogen (hPL), C) progesterone, D) alphafetoprotein (AFP), E) Ischemia-modified albumin (IMA), F) Lactate dehydrogenase (LDH) and G) Pregnancy-associated plasma protein A (PAPP-A). * p<0.05, ** p<0.01, ***p<0.001.

Figure 3. Relationship between placentally derived factors, placental weight and mRNA expression.

A) serum hCG was not related to placental weight, B) There was no difference between hCG mRNA and pregnancy outcome, C) serum hPL positively correlated to placental weight (*** p<0.001), D) There was no difference between hPL mRNA expression and pregnancy outcome, E) serum progesterone positively correlated to placental weight (** p<0.01), F) There was no difference between 3β-HSD mRNA expression and pregnancy outcome.