Around half of pregnant mums will snore in their third trimester. This is due to increased body weight and the increase of estrogen and progesterone.
Australian sleep researchers studied a group of mums-to-be and found those who did snore during the last stages of pregnancy were at increased risk of developing high blood pressure.
High blood pressure in pregnancy is linked to restricted growth in unborn babies and reduced blood flow to the placenta.
The study, led by Professor Sullivan in Australia, found nearly half of the pregnant mums studied snored for 20 per cent of the night during their third trimester. Some of the women were not aware that they did it.
A further study, conducted by Alison Fung at Mercy Hospital for Women in Melbourne, found a more serious form of snoring, sleep apnea, was linked to reduced growth in babies. Sleep apnoea is more common in obese woman, who are also more at risk of stillbirth.
"There's not much we can do about obesity, but if we found some of the complications associated with it can be treated that would be very exciting," said Dr. Fung.
"In the past, sleep apnea had been rarely studied in pregnant women because it largely affected men, but the hormones and weight gain in pregnancy put women at extra risk. Pregnancy is a particularly stressful time. You are putting your body through a stress test of life".
If you're finding yourself snoring in pregnancy, there are a few things you can try:
Sticking to a healthy and balanced diet
Taking regular, gentle exercise
Sleeping on your side, not your back, and raising your head slightly with a pillow