Maternal perception of decreased fetal movements is independent of infant size

Fetal movements are often used as a surrogate for fetal wellbeing. Previous research suggests a link between maternal perception of decreased fetal movements (DFM) and small-for-gestational-age (SGA) infants. The aim of this study was to investigate the association between maternal presentation with DFM and birth-weight centile categories at a large Australian perinatal center.

This was a retrospective study of non-anomalous singleton infants born at ≥ 28 + 0 weeks' gestation between January 2016 and October 2020 at the Mater Mothers' Hospital in Brisbane, Australia. The primary outcome was the rate of DFM according to birth-weight centile category. Maternal demographic characteristics included age, body mass index, ethnicity, parity, medical conditions and previous stillbirth. The association between DFM and birth-weight centile was evaluated using adjusted multinomial regression models. Robust standard errors were used to account for clustering at the patient level. Wald tests and Akaike's and Bayesian information criteria were used to evaluate models.

Over the 5-year study period, 45 042 women met the inclusion criteria. Of these, 6690 (14.9%) women presented with DFM. Of the DFM cohort, 80.9% (5411/6690) had only one presentation with DFM, and 19.1% (1279/6690) had two or more presentations. The overall stillbirth rate was similar in women with DFM (0.1% (8/6690)) and those without DFM (0.1% (50/38 352)). There was no association between DFM (either single or multiple) and infant birth-weight centile.

This study suggests that presentation with DFM is not associated with infant size. Clinicians should consider additional risk factors and the overall clinical context when deciding appropriate management. DFM is not necessarily an indication for an immediate or urgent ultrasound scan to assess fetal size. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.