Are reduced fetal movements "merely" a maternal perception or truly a reflection of umbilical cord complications? A clinical trial.

OBJECTIVE

To characterize obstetric outcomes and the association with umbilical cord (UC) complications among women complaining of reduced fetal movements (RFMs).

METHODS

This retrospective cohort compared women with a perception of RFMs within 2 weeks prior to delivery with women who reported no changes in fetal movements in terms of maternal characteristics and neonatal outcomes. A primary outcome of UC complications at delivery was defined. Multivariable regression analysis was performed to identify independent associations with RFMs and UC complications.

RESULTS

In all, 46 103 women were included, 2591 (5.6%) of whom reported RFMs and 43 512 (94.4%) in the control group. Compared with controls, the RFM group was more likely to be nulliparous (42.6% vs 32.2%, P < 0.001), smokers (6.4% vs 5.4%, P = 0.029), or obese (body mass index >30) (16.4% vs 11.6%, P < 0.001). They were also more likely to have an anterior placenta (56.2% vs 51.8%, P < 0.001) and poly/oligohydramnios (0.7% vs 0.4%, P = 0.015 and 3.6% vs 2.1%, P < 0.001, respectively). Induction of labor was more common in the RFM group (33.9% vs 19.7%, P < 0.001), as well as meconium (16.8% vs 15.0%, P = 0.026) and vacuum extractions (10.1% vs 8.0%, P < 0.001). Higher rates of stillbirth and the severe composite neonatal outcome were observed in the RFM group (1.5% vs 0.2%, P < 0.001 and 0.6% vs 0.3%, P = 0.010, respectively). The RFM group was characterized by higher rates of triple nuchal cord (P = 0.015), UC around body or neck (32.2% vs 29.6%, P = 0.010), and true knot (2.3% vs 1.4%, P = 0.002). Multivariable logistic regression found RFMs to be independently associated with triple nuchal cord and with a true cord knot. A sub-analysis including only cases of stillbirth (n = 127) revealed even higher rates of UC complications: 7% of all stillbirths presented with a true cord knot (20% true knots were found in stillbirths preceded by RFMs vs 6.1% in stillbirth cases without RFMs). Additionally, 33.8% of all stillbirths presented with nuchal cord (40% preceded by RFMs vs 33.3% without RFMs).

CONCLUSIONS

RFMs are associated with increased risk of UC complications observed at delivery, as well as increased risk of stillbirth and neonatal adverse outcomes.