Left Side or Right Side in Pregnancy? What the Guidance Says

What Tommy's says

Tommy's says sleeping on your left side has not conclusively been shown to lower your risk compared with sleeping on your right. Tommy's says one of the smaller research studies, from Auckland, New Zealand, found that women who slept on their left side on the last night of pregnancy halved their risk of stillbirth compared with those who slept on their right. Tommy's says the same finding has not been seen in any other trial, and that there have been 3 other published research studies since then.

What the NHS says

The NHS says the safest position to fall asleep in is on your side, either left or right.

What Cleveland Clinic says

Cleveland Clinic ob-gyn Salena Zanotti, MD, says ob-gyns have traditionally advised patients to sleep on their left side, because the inferior vena cava is on the right. She says the evidence today shows that if you're truly on your side, you're still going to get good blood flow, regardless of the side you're on. Zanotti also says that if you're a right-sided sleeper, you're fine that way, too.

Pillows

We don't claim a pillow changes anything described above.

The honest part

This is general information, not medical advice. For questions about pregnancy sleep positions, follow the guidance of a qualified healthcare professional.

Where to go from here

Can You Sleep on Your Back While Pregnant? What the Guidance Says covers what the sources say about back sleeping.

Sources

Tommy's — Sleep position in pregnancy Q&A (last reviewed 11 June 2026).

NHS — Preventing stillbirth (last reviewed 24 April 2024).

Cleveland Clinic — "Is It Really All That Bad To Sleep on Your Back While Pregnant?", with Salena Zanotti, MD (23 September 2024).

Checked by Queen Rose on 6 October 2026.