Understanding the associations and significance of fetal movements in overweight or obese pregnant women: a systematic review

Introduction: Presentation with decreased fetal movement (DFM) is associated with fetal growth restriction and stillbirth. Some studies report that DFM is frequent among overweight or obese mothers. We aimed to determine the significance and associations of fetal movements in women of increased body size.

Material and methods: This systematic review was conducted in accordance with the PRISMA statement and the protocol was registered with PROSPERO (CRD42016046352). Major databases were explored from inception to September 2017, using a predefined search strategy. We restricted inclusion to studies published in English and considered studies of any design that compared fetal movements in women of increased and normal body size. Two authors independently extracted data and assessed quality.

Results: We included 23 publications from 19 observational studies; data were extracted from 10 studies. Increased maternal body size was not associated with altered perception of fetal movement (four studies, 95 women, very low-quality evidence), but was associated with increased presentation for DFM (two cohort studies, 20 588 women, OR 1.56, 95% CI 1.27-1.92: three case-control studies, 3445 women, OR 1.32, 95% CI 1.12-1.54; low-quality evidence). Among women with DFM, increased maternal body size was associated with increased risk of stillbirth and fetal growth restriction (one study, 2168 women, very low-quality evidence).

Conclusions: This systematic review identified limited evidence that women with increased body size are more likely to present with DFM but do not have impaired perception of fetal movements. In women with DFM, increased body size is associated with worse pregnancy outcome, including stillbirth.