Q: Is it true that I can’t sleep on my back while pregnant?

Answered by: Dr Mohamad Faisol Mihat, Obstetrician & Gynaecologist (O&G), Pantai Hospital Klang (PHK)

Good sleep is important part for health and wellbeing. Humans spend approximately one third of their life asleep. Hence good quality of sleep will affect another two third of human life. Unfortunately, sleeping position has impacts on pregnancy.

Sleep on back (supine position) might cause pregnant women to have breathlessness. This occurs as diaphragm and lungs been pushed by the gravid uterus. In addition, supine position may aggravate heartburn,” gastroesophageal reflux disease” (GERD) a common problem in pregnancy. During pregnancy, women are susceptible for low back pain as a result of changes in spinal muscle length and posture. For comfort, pregnant women will often naturally avoid lying on their back at night.

During pregnancy, after 3rd months (12 weeks and beyond) growing uterus has effect on the haemodynamic system. It is more profound in late pregnancy (after 28 weeks). In particularly, during lying on the back the gravid uterus compresses large vessel (inferior vena cava) resulting restriction of blood flow to the heart. Hence less blood pump out from the left side of the heart to the other parts of body especially to the growing fetus and placenta. Failure to prevent this might cause maternal supine hypotensive syndrome (also known as inferior vena cava compression syndrome). This can result negative sequalae to the blood exchanges between fetus and mother.

More recently there is emerging evidence that if woman sleeps on their back , this put her at increased risk of stillbirth ( Owusu et al. 2013; Gordon et al 2015; McCowan et al.2017).The study found that going to sleep position on back increase risk of stillbirth 2.5 to 8 times higher. These risks can be avoided if women sleep on their side. Right and left side is equally safe for women who is pregnant.
Thus, pregnant women may benefit from education and prevention intervention. Several methods can be used to improve position during sleep such as use of mattress or wedges pillow. Even simple intervention, “tennis ball technique” (TBT) might help reduce pregnant lady from sleep on their back!

In conclusion, pregnant women are encouraged to sleep on their sides at night to improve quality of sleep and keep the baby healthy.