Myth 2: Fetuses slow down at the end of pregnancy
There is a very common myth that fetuses slow down at the end of pregnancy, especially once labor has started. A study in the Journal of Physiology continuously monitored term fetuses when mom was both awake and asleep. The study also looked at the effect on fetal heart rate and fetal activity based on different maternal positions. The study found the fetuses spent around 90% of the day with active movements and with reactive nonstress tests (NSTs).3 A 2019 study looking at fetal movement at term and preterm in third-trimester patients illustrated that fetal movement does not decrease in frequency or strength at term. It found that only 6% of patients noted decreased strength and 14% decreased frequency of movements at term. Furthermore, 59% reported an increase in strength, and nearly 39% reported an increase in frequency of fetal movements at term.4 We must educate patients that a change in frequency or strength of movements is not normal or expected, and they must call if concerned about a change.
Myth 3: Try juice, ice water, or food before coming in for evaluation
A common set of advice when a patient calls with a complaint of decreased fetal movement is to suggest a meal or something sugary, although there is little or no evidence to support this. A randomized controlled trial found maternal perception of increased fetal movement was similar among the two groups. Giving something sugary at NST also was not shown in this study to improve reactivity.5 Another randomized, double placebo blind study was done to answer the question of whether glucose via IV helped improve fetal movements and decreased the need for admission for induction or further monitoring. In this study, no difference in outcome is found.6
When a patient calls with decreased fetal movement, advice should be to come and be evaluated, not recommendation of measures like ice water, orange juice, or sugary meal because it is not supported by the literature. This incorrect message also may further the false impression that a baby who is not moving is most likely sleeping or is simply in need of sugar, not that the baby may be at risk for impending stillbirth. The Perinatal Society of Australia and New Zealand and Royal College of Obstetricians and Gynecologists have fetal movement protocol that both discourage this advice and encourage immediate evaluation of patients with complaint of concerning fetal movement change.7,8
Myth 4: An increase in fetal movement is not of concern
I used to believe that increased fetal movement is never of concern. However, the STARS study illustrated that a concerning increase in fetal movement often is noted just before the diagnosis of stillbirth. A single episode of excessively vigorous activity which often is described as frantic or crazy is associated with an odds ratio for stillbirth of 4.3. In the study, 30% of cases reported this, compared with 7% of controls.9 In our practice, we manage mothers who call with this concern the same way as a decreased fetal movement complaint, and bring the mother in immediately for evaluation.