What is a likely cause of a fetal heart rate of 180 beats/minute at 38 weeks?

A fetal heart rate of 180 beats per minute at 38 weeks can be indicative of several potential factors, with maternal infection being a significant cause. When a mother has an infection, it can lead to systemic changes that affect fetal heart rate. The fetus is particularly sensitive to maternal physiological changes, and an increase in maternal temperature or infection-related stress responses can elevate the fetal heart rate.

In this context, other conditions such as umbilical cord compression might lead to variable or decelerated heart rates rather than a sustained increase. While factors like mild dehydration and maternal anxiety can also influence fetal heart rate, they typically do not elicit such an acute elevation as seen in cases of maternal infection. The distinction lies in recognizing that a significant and sudden rise in fetal heart rate is more closely associated with physiological stressors like infections that provoke a more pronounced reaction in the fetus.