OSA in pregnancy: Who to test, how to screen, and does treatment help?
Diagnosis of OSA in the pregnant population
In the general population, in-laboratory polysomnogram (PSG) is the gold standard diagnostic test. However, for patients in whom uncomplicated OSA is suspected with a moderate to high pretest probability, unattended home sleep apnea testing (HSAT) is a reasonable initial study. On the other hand, in-lab PSG is recommended in mission-critical workers and when coexisting respiratory sleep disorders, or nonrespiratory sleep disorders, are suspected. For individuals who are pregnant and suspected of having OSA, the guideline suggests that HSAT is a reasonable diagnostic tool, as many level III devices have demonstrated good agreement between the respiratory disturbance index (RDI) and apnea-hypopnea index (AHI) measured by PSG.6 Notably, most studies have examined the performance of level III devices in late pregnancy in populations with obesity; hence, the performance of these devices in early pregnancy when risk for OSA is lower, or more subtle forms of SDB may be more common, is less clear but may be an acceptable first-line test.
The guideline did not provide recommendations for next steps following an inconclusive, technically inadequate, or negative HSAT. However, recommendations to proceed with in-lab PSG in individuals with clinical suspicion for OSA and a negative HSAT is a reasonable approach, keeping in mind the time restrictions of pregnancy. The more delayed the diagnosis, the less time there will be for initiation of and acclimation to therapy to maximize potential benefits during pregnancy. HSAT is especially practical and convenient for individuals with young families. The guideline does not recommend the use of overnight oximetry for diagnostic purposes.1
The postpartum period is usually associated with weight loss and reversal of pregnancy physiology. Generally, the decision to perform a repeat sleep study following weight loss is individualized, based on factors such as improved symptoms or sustained, significant weight loss. Though data show improvement in AHI following delivery, small studies show persistent OSA in nearly half of individuals diagnosed in pregnancy. Hence, as pregnancy increases the risk for OSA, and given that the postpartum status is not always associated with resolution of OSA, the guideline recommends considering repeat diagnostic testing in the postpartum period.1 The decision to repeat testing also depends on whether OSA or OSA symptoms predated pregnancy, on the persistence of symptoms, and the degree of weight loss with delivery and the postpartum body habitus.
Treatment of OSA in the pregnant population
The guideline recommends behavior modification in OSA similarly to individuals who are not pregnant (avoidance of sedatives, smoking, and alcohol).1 However, weight loss is not recommended in pregnancy due to the potential for harm to the fetus.
The gold standard treatment for people who are pregnant and have OSA is continuous positive airway pressure (CPAP). Treatment of OSA in pregnancy is complicated by the fact that very few women are referred to sleep practices due to time restrictions and logistical reasons, and that data demonstrating improved pregnancy outcomes with CPAP are scarce, limiting the prioritization of OSA management. However, expert consensus considers a theoretical benefit in the context of lack of current evidence of harm from treatment. Hence, at this point, the guideline recommends counseling around CPAP therapy be aimed at improvement in symptoms, AHI, and quality of life, rather than pregnancy-specific outcomes.1 This recommendation was based on observations from small case series that demonstrated improved breathing parameters during sleep and symptoms, and small randomized controlled trials (RCT), limited by short-term exposure to the intervention. However, since the publication of this guideline, a large RCT that randomized pregnant women with SDB to CPAP or usual care has demonstrated significantly lower diastolic blood pressure, an altered diastolic blood pressure trajectory, and a lower rate of preeclampsia in the group treated with CPAP compared with usual care.7
This guideline provides helpful insight on who to screen and how to manage OSA in pregnancy but additional research is needed to elucidate benefits of treatment and its effects on maternal and neonatal outcomes. Multidisciplinary collaborations between obstetric and sleep teams are necessary to ensure that screening and diagnostic strategies result in management change for improved outcomes.
References
1. Dominguez JE, Cantrell S, Habib AS, et al. Society of Anesthesia and Sleep Medicine and the Society for Obstetric Anesthesia and Perinatology Consensus Guideline on the screening, diagnosis and treatment of obstructive sleep apnea in pregnancy. Obstet Gynecol. 2023;142(2):403-423.
2. Bourjeily, G, Danilack C, Bublitz M, Muri J, Rosene-Montella K, Lipkind H. Maternal obstructive sleep apnea and neonatal birth outcomes in a population based sample. Sleep Med. 2000;66:233-240.
3. Malhamé I, Bublitz MH, Wilson D, Sanapo L, Rochin E, Bourjeily G. Sleep disordered breathing and the risk of severe maternal morbidity in women with preeclampsia: a population-based study. Pregnancy Hypertens. 2022;30:215-220.
4. Izci-Balserak B, Zhu B, Gurubhagavatula I, Keenan BT, Pien GW. A screening algorithm for obstructive sleep apnea in pregnancy. Ann Am Thorac Soc. 2019;16(10):1286-1294.
5. Louis J, Koch MA, Reddy UM, et al. Predictors of sleep-disordered breathing in pregnancy. Am J Obstet Gynecol. 2018;218(5):521.e1.e12.
6. Sharkey K, Waters K, Millman R, Moore R, Martin SM, Bourjeily. Validation of the Apnea Risk Evaluation System (ARES) device against laboratory polysomnogram in pregnant women at risk for obstructive sleep apnea syndrome. J Clin Sleep Med. 2014;10(5):497-502.
7. Tantrakul V, Ingsathit A, Liamsombut S, et al. Treatment of obstructive sleep apnea in high-risk pregnancy: a multicenter randomized controlled trial. Respir Res. 2023;24(1):171.
