It is possible that pregnant women can develop sleep apnoea during pregnancy. In studies of non-pregnant populations, a 20 % weight gain has a very significant impact on the development of OSA. Since pregnant women often have similar weight gains it is theoretically possible that many will develop breathing problems that can affect the developing fetus.
Snoring is the lowest level of sleep disordered breathing. Only 4% of healthy young women snore; the fact that reports of snoring increase to 25% of pregnant women by the third trimester, points to other possible negative side-effects of compromised breathing. The more overweight a woman is before she gets pregnant, the more likely there will be alterations in her breathing at night. Studies of pregnant women show that snorers have higher blood pressure than non-snorers.
Sleep apnoea is known to increase blood pressure in patients, in the beginning this is seen only during sleep and could be missed at a medical appointment. There is a pregnancy-induced hypertension that can develop after the 20th week of pregnancy and can cause many problems with the developing baby and the mother’s health. When this gets out of control, it is called preeclampsia or, worse yet, eclampsia and can be fatal. Known risk factors for preeclampsia include family history, advancing maternal age, obesity, chronic hypertension and kidney disease.
As of now, no one knows if sleep apnoea, and the intermittent lack of oxygen it causes at night, causes the blood vessel breakdown in the placenta seen with preeclampsia or if the retention of fluid from the preeclampsia causes the breathing problems due to tissue swelling all over the mother’s body. Obstetricians are always on the lookout for this condition and will treat it aggressively.
Treatment of Sleep Apnoea during pregnancy:
Who should be treated?
Any woman who is diagnosed with severe sleep apnoea or who has drops in her blood oxygen level below 90% must be treated as quickly as possible. If the mother is not breathing properly at night, the fetus can suffer growth retardation which impacts the baby’s survival after delivery.
How should she be treated?
CPAP (Continuous Positive Air Pressure): There is no other option that will be as helpful for the fetus. It is not sexy, or comfortable, but it is only required during the remainder of the pregnancy and will help protect the baby. Oral appliances, though effective, require time to fabricate and up to three months to be maximally effective. By the time effective oral appliance therapy is instituted, the pregnancy will be over.
Surgery: is less effective than any other therapy for sleep apnea and not an approach to be taken during pregnancy.
What to do after delivery?
Women who develop sleep apnoea during pregnancy should have a follow-up sleep study after regaining her normal weight (2-3 months after delivery) This will verify if the sleep apnea has resolved. Some women take longer to shed the extra weight of pregnancy and may continue to have sleep apnea. Since sleep apnea makes people feel sleepy, and a new baby also disrupts a mother’s sleep, treatment is necessary to keep the new mother from experiencing severe sleep deprivation. Some researchers have wondered if this loss of sleep may be part of the cause of “post-partum depression”.
Source: Pien GW; Schwab RJ. Sleep disorders during pregnancy. SLEEP 2004;27(7):1405-17.