‘Fetal activity during pregnancy denotes a baby’s wellbeing. Sleeping on the sides shows normal fetal activity than sleeping on the back.’
Researchers at the University of Auckland investigated sleep position of pregnant
women by setting up an infrared video camera to record their position as they
slept. They also continuous recorded the heart rate of the women and fetus
overnight using an ECG device.
When the mother slept on her back, the fetus was less active. Fetal activity
is one measure of its wellbeing. Fetuses were only in an active state
when the mother was on her left or right side
. When the mother
changed position during sleep, for example from her left side to sleeping on
her back, the baby quickly changed activity state and became quiet or still.
This research involved 30 pregnant women at 34-38 weeks gestation and all of
them were healthy with healthy babies. The researchers are now investigating
pregnancies where the fetus is not growing properly or the mother has reported
decreased fetal movements, as both situations have been associated with an
increased risk of stillbirth.
Peter Stone, one of the lead investigators on the study said, "In the
situation where the baby may not be healthy, such as those with poor growth,
the baby may not tolerate the effect of maternal back sleeping."
The authors added, "We are suggesting that there is now sufficient evidence
to recommend mothers avoid sleeping on their back in late pregnancy, not only
because of the epidemiological data but also because we have shown it has a
clear effect on the baby."