Sleep apnea significantly affects pregnancy, raising the risk of several serious complications for both mother and baby. Pregnant women with obstructive sleep apnea face higher rates of preeclampsia, gestational diabetes, fetal growth restriction, and cesarean delivery. The condition is also more common during pregnancy than many people realize, with prevalence estimates ranging from 3.6% to 27% depending on the population studied.
How Common Sleep Apnea Is During Pregnancy
Sleep apnea can develop for the first time during pregnancy or worsen if it was already present. A large study of over 3,700 pregnant women found that 3.6% had sleep apnea in early pregnancy (6 to 15 weeks), and that number jumped to 8.3% by mid-pregnancy (22 to 31 weeks). The severity also increases as pregnancy progresses. Among those diagnosed, 3% had moderate to severe sleep apnea in early pregnancy compared to 8% by mid-pregnancy.
Several pregnancy-related changes drive this increase. Weight gain, fluid retention, and hormonal shifts all narrow the airway. The growing uterus pushes the diaphragm upward, reducing lung capacity, especially when lying on your back. These changes mean even women who never snored before pregnancy can develop clinically significant breathing pauses during sleep.
Preeclampsia and High Blood Pressure
The link between sleep apnea and dangerous blood pressure problems during pregnancy is one of the strongest and most concerning associations. In one study, 82% of women with gestational hypertension had sleep apnea, compared to 45% of women with normal blood pressure. After adjusting for factors like age, weight, and prior pregnancies, women with sleep apnea were roughly 7.5 times more likely to develop gestational hypertension.
Among women with hypertensive disorders who also snored, the risk of having sleep apnea was about twice as high as in non-snoring women with hypertension. The mechanism appears to involve repeated drops in oxygen during sleep, which triggers inflammation and damages blood vessel walls. Over time, this contributes to the same kind of vascular dysfunction that underlies preeclampsia, a condition where blood pressure spikes and organs like the kidneys and liver start to suffer.
Gestational Diabetes Risk
Women with sleep apnea during pregnancy are also substantially more likely to develop gestational diabetes. A study of nearly 1.6 million deliveries found that sleep apnea was associated with about 50% higher odds of gestational diabetes after adjusting for obesity, age, race, and other factors. Smaller studies have found even larger effects. One found that women diagnosed with sleep apnea in early pregnancy had 3.5 times the odds of developing gestational diabetes. Another reported odds more than six times higher, though with a small sample size.
What makes this particularly noteworthy is how little sleep disruption it takes. In the second trimester, even very mild breathing disturbances during sleep, below the standard threshold used to diagnose sleep apnea in non-pregnant adults, were significantly associated with increased diabetes risk. The repeated oxygen dips appear to impair how the body processes blood sugar, compounding the insulin resistance that pregnancy already creates.
Effects on the Baby
Maternal sleep apnea doesn’t just affect the mother. The intermittent drops in oxygen can reduce blood flow to the placenta, potentially limiting the nutrients and oxygen reaching the baby. Sleep apnea in pregnancy has been linked to fetal growth restriction (when a baby measures significantly smaller than expected), low birth weight, preterm delivery, and higher rates of admission to the neonatal intensive care unit.
Women with sleep apnea are also about 60% more likely to deliver by cesarean section. This increased rate is likely related to both the direct effects of the condition and the complications it causes, since preeclampsia and fetal growth problems often lead to earlier or surgical deliveries.
Why Screening Is Tricky
Despite these risks, there were no formal guidelines for screening or treating sleep apnea in pregnancy until 2023, when a joint expert panel from the Society of Anesthesia and Sleep Medicine and the Society for Obstetric Anesthesia and Perinatology published the first consensus recommendations. The American College of Obstetricians and Gynecologists endorsed the document as an educational tool.
Part of the challenge is that standard screening questionnaires don’t work as well in pregnant women. The STOP-Bang questionnaire, widely used to screen for sleep apnea in the general population, has a sensitivity of only about 63% in the second trimester. That means it misses roughly one in three pregnant women who actually have the condition. Symptoms like fatigue, frequent nighttime awakenings, and weight gain overlap so heavily with normal pregnancy that sleep apnea often goes unrecognized.
If you snore loudly, wake up gasping, or have persistent daytime exhaustion that feels out of proportion to your sleep schedule, raising those symptoms with your provider is worthwhile. Home sleep testing devices can diagnose the condition without requiring an overnight stay in a sleep lab.
Treatment During Pregnancy
The primary treatment for sleep apnea during pregnancy is the same as outside of pregnancy: continuous positive airway pressure, or CPAP. This involves wearing a mask connected to a small machine that gently keeps your airway open while you sleep. A meta-analysis of six studies involving 809 pregnant women found that CPAP use was associated with a 35% reduction in the risk of gestational hypertension and a 30% reduction in the risk of preeclampsia. Those are meaningful reductions for conditions that can become life-threatening.
CPAP is generally safe during pregnancy and does not pose risks to the baby. The main barrier is comfort and adherence. Nasal congestion, which is already common in pregnancy, can make the mask harder to tolerate. Trying different mask styles and using a heated humidifier attachment can help. Positional changes, like sleeping on your side rather than your back, may also reduce mild sleep apnea, though they’re typically not sufficient on their own for moderate or severe cases.
Sleep Apnea Often Persists After Delivery
Many women assume that pregnancy-related sleep apnea will disappear once the baby is born, but the data suggest otherwise. In one study, 37% of women had sleep apnea in the third trimester, and that proportion barely changed at 6 to 15 weeks postpartum, with 35% still testing positive. Of those retested at 6 to 8 months after delivery, 73% still had sleep apnea.
The picture is complicated because it’s not always the same women affected. Some women whose sleep apnea resolved after delivery were replaced by others who newly tested positive in the postpartum period. All of the newly developing cases were mild. But the overall takeaway is clear: gestational sleep apnea resolves much more slowly than conditions like gestational diabetes or pregnancy-related hypertension, which typically improve within days or weeks of delivery. For some women, pregnancy may unmask a predisposition to chronic sleep apnea that persists long-term. If you were diagnosed during pregnancy, follow-up testing in the months after delivery is important rather than assuming the problem has resolved on its own.