decreased fetal movements (DFM or RFM)

Introduction

most women can feel fetal movements by 20 weeks gestation and these rapidly acquire a regular pattern
although fetal movements tend to plateau by 32 weeks of gestation, there is no reduction in the frequency of fetal movements in the late third trimester
by term, the average number of generalised movements per hour is 31 (range 16–45), with the longest period between movements ranging from 50 to 75 minutes.¹⁾
over half of women who have a stillbirth / FDIU reported DFM, however, reassuringly, 70% of pregnancies with a single episode of reduced fetal movements (RFM) are uncomplicated and do not progress to stillbirth. Those with multiple occasions of RFM have twice the risk of a poor perinatal outcome.
maternal concern of decreased foetal movements (DFM) in the 3rd trimester is a major risk of potential impending stillbirth and is an indication for emergent investigation and management and may be a trigger for emergency LUSCS pending CTG and further assessment

Ix and Mx in the 2nd trimester is still unclear as CTG is not useful as a guide to care and planned early delivery before 28wks may have more risks than benefits given the extreme prematurity

confirm the presence of a fetal heartbeat by auscultation with a Doppler handheld device or ultrasound to exclude fetal death in utero

confirm the presence of a fetal heartbeat by auscultation with a Doppler handheld device or ultrasound to exclude fetal death in utero
if fetal movements have never been felt by 24 weeks of gestation, consider referring the woman to an obstetrician.
“There are no studies looking at the outcome of women who present with RFM between 24+0 and 28+0 weeks of gestation. The fetal heartbeat should be confirmed to check fetal viability. History must include a comprehensive stillbirth risk evaluation, including a review of the presence of other risk factors associated with an increased risk of stillbirth. Clinicians should be aware that placental insufficiency may present at this gestation. There is no evidence to recommend the routine use of CTG surveillance in this group. If there is clinical suspicion of fetal growth retardation, consideration should be given to the need for ultrasound assessment. There is no evidence on which to recommend the routine use of ultrasound assessment in this group.” ²⁾
Testing for Kleihauer should be considered if there is any history of recent trauma.
Ultrasound assessment to exclude fetal neuromuscular abnormalities should be considered.
Ultrasound to assess the fetal middle cerebral artery (MCA) blood flow peak systolic velocity should be considered if there is any possibility of fetal anaemia.

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