Continuous Positive Airway Pressure Therapy in Gestational Diabetes With Obstructive Sleep Apnea: A Randomized Controlled Trial

Effect of Continuous Positive Airway Pressure or Positional Therapy Compared to Control for Treatment of Obstructive Sleep Apnea on the Development of Gestational Diabetes Mellitus in Pregnancy: Protocol for Feasibility Randomized Controlled Trial

BACKGROUND

Obstructive sleep apnea (OSA) is a common sleep disorder, and in pregnancy, it is associated with an increased risk of complications, including gestational diabetes mellitus and preeclampsia. Supine sleep may worsen OSA, and in pregnancy, it is associated with an increased risk of stillbirth due to effects on fetomaternal blood flow. Continuous positive airway pressure (CPAP) therapy is considered the gold-standard treatment for moderate to severe OSA, although compliance is frequently poor; positional therapy (PT) is generally less effective than CPAP in nonpregnant patients but may be better tolerated and more accessible during pregnancy. There is limited data on whether widespread, early screening for sleep disorders in pregnant women with symptoms of sleep-disordered breathing or at high risk of metabolic complications and subsequent early intervention with CPAP or PT attenuates fetomaternal risks.

OBJECTIVE

This study aims to determine the feasibility of conducting a randomized controlled trial to assess improved fetomaternal outcomes in a high-risk pregnant population with OSA, using CPAP or PT, initiated by the 16th week of gestation.

METHODS

This study is a randomized, controlled, open-label feasibility study in which pregnant women with an apnea-hypopnea index (AHI) or respiratory disturbance index (RDI) ≥5 are treated with CPAP (auto-titrating and fixed pressure) or positional therapy from early gestation (by 16 weeks) until delivery. The primary outcome is the feasibility of the study protocol and the development of gestational diabetes mellitus by the 28-week gestation period. Secondary outcomes include the development of hypertensive disorders of pregnancy (HDP), maternal weight gain, uterine artery blood flow, glycemic control during pregnancy (in participants who develop gestational diabetes), changes in maternal circulating biomarkers, and neonatal birthweight complications. Polysomnography at 28- to 32-week gestation period, postpartum polysomnography, therapy compliance, and patient acceptability are also assessed.

RESULTS

The trial commenced on September 30, 2019. The trial is ongoing as of August 6, 2024.

CONCLUSIONS

The trial intends to contribute to the growing evidence base to support the need for the identification and treatment of OSA occurring during pregnancy and to assess the feasibility of the study protocol. This will be the first trial to compare the early initiation of CPAP (auto-titrating and fixed pressure) and positional therapy in pregnant women from early gestation, providing alternative therapies for the treatment of OSA in this important population.

TRIAL REGISTRATION

Australian New Zealand Clinical Trials Registry ACTRN12619001530112; https://tinyurl.com/yctdzs4u.

INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID)

DERR1-10.2196/51434.

Patterns of adherence to continuous positive airway pressure and mandibular advancement splints in pregnant individuals with sleep-disordered breathing

PURPOSE

Night-to-night adherence to sleep-disordered breathing (SDB) treatment with either continuous positive airway pressure (CPAP) or mandibular advancement splints (MAS) in pregnancy has not been well characterized. The objective of this study was to assess night-to-night adherence patterns from existing CPAP and MAS data in pregnancy.

METHODS

Three separate pregnancy cohorts evaluating treatment for SDB in the second and third trimester were used: 1) CPAP in gestational diabetes mellitus (GDM), 2) CPAP in hypertensive disorders of pregnancy (HDP), and 3) mandibular advancement splints (MAS). The first 30 days of objective adherence data obtained from CPAP and MAS devices were used in this descriptive analysis.

RESULTS

Data from 37 CPAP users and 15 MAS users was analyzed. For the GDM and HDP cohorts, three patterns of adherence were observed: 1) consistent CPAP users (38%), 2) improved CPAP usage after initial adaptation (16%), and 3) inconsistent CPAP users (46%). For the MAS cohort, the three observed patterns of adherence were: 1) consistent MAS users (47%), 2) initial usage with subsequent decrease in adherence (20%), and 3) inconsistent MAS users (33%). Participant characteristics (demographics, disease severity) were similar between adherence groups, with the exception of longer total sleep time in consistent CPAP users of the GDM cohort and greater gestational age in consistent CPAP users of the HDP cohort.

CONCLUSION

Overall, objective night-to-night adherence patterns revealed that almost half of CPAP and MAS users had difficulty adapting to treatment in the first 30 days of treatment. Early usage patterns in pregnancy may provide insight into identifying patients who are at risk for poor adherence and for developing tailored and timely interventions to enhance adherence to therapy.

TRIAL REGISTRATION

ClinicalTrials.gov Identifiers: NCT02245659, NCT03309826, NCT03138291.

[Obstructive apnea hypopnea syndrome in pregnancy]

Obstructive sleep apnea hypopnea syndrome (OSA) in pregnant women is an under-diagnosed but common condition, due to the numerous physiological changes favoring upper airway collapse. Risk factors such as significant weight gain during the 1st trimester, maternal age and parity should be systematically investigated. Diagnosis is made by sleep recording. OSA can lead to maternal and fetal complications (gestational diabetes, eclampsia, intrauterine growth restriction, prematurity…) during pregnancy, delivery and the post-partum period. It is therefore essential to treat apneic patients as early as possible in pregnancy. Treatment includes hygienic and dietary measures, as well as continuous positive airway pressure (CPAP). Systematic post-partum follow-up with polygraphic monitoring should be proposed.

Continuous Positive Airway Pressure Treatment and Hypertensive Adverse Outcomes in Pregnancy: A Systematic Review and Meta-Analysis

Importance

Pregnancy may contribute to the development or exacerbation of obstructive sleep apnea (OSA) and increase the risk of gestational complications. Continuous positive airway pressure (CPAP) is the first-line and criterion standard treatment for OSA and is regarded as the most feasible choice during pregnancy. However, the association between CPAP therapy in pregnant women with OSA and reduced gestational complications remains inconclusive.

Objective

To investigate the association between CPAP therapy in pregnant women with OSA and the reduction of adverse hypertensive outcomes during gestation.

Data Sources

Keyword searches of PubMed, Embase, and the Cochrane Database of Systematic Reviews and Clinical Trials were conducted from inception to November 5, 2023.

Study Selection

Original studies reporting the treatment effect of CPAP use on lowering hypertension and preeclampsia risks in pregnant women with OSA were selected.

Data Extraction and Synthesis

The Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline was followed in the reporting of reviews. Data were independently extracted by 2 authors. Random-effects model meta-analyses were performed and risk ratios (RRs) reported. Subgroup analysis, meta-regression based on age and body mass index (BMI; calculated as weight in kilograms divided by height in meters squared), and publication bias assessment were also conducted.

Main Outcome and Measures

The primary outcome was the RR of gestational hypertension and preeclampsia between pregnant women with OSA receiving CPAP treatment and those who did not receive CPAP treatment.

Results

Six original studies in 809 participants (mean age, 31.4 years; mean BMI, 34.0) were identified and systematically reviewed for meta-analysis. The pooled results showed significant differences between the intervention (CPAP use) and the control (non-CPAP use) groups in reducing the risk of gestational hypertension (RR, 0.65; 95% CI, 0.47-0.89; P = .008) and preeclampsia (RR, 0.70; 95% CI, 0.50-0.98; P = .04). Meta-regression revealed that patients' age (coefficient, -0.0190; P = .83) and BMI (coefficient, -0.0042; P = .87) were not correlated with reduction of risk of hypertension and preeclampsia.

Conclusions and Relevance

These findings suggest that implementing CPAP treatment in pregnant women with OSA may reduce the risk of gestational hypertension and preeclampsia.

Positive Airway Pressure Treatment of Obstructive Sleep Apnea-Hypopnea in Hypertensive Disorders of Pregnancy: A Pilot Randomized Proof-of-Concept Clinical Trial

Rationale: Maternal obstructive sleep apnea-hypopnea (OSAH) is associated with hypertensive disorders of pregnancy (HDP). OSAH treatment with positive airway pressure (PAP) in the general population lowers blood pressure (BP). However, there are limited data on the effects of PAP therapy in maternal OSAH. Objectives: Our primary objective was to assess the feasibility of recruitment to a pilot randomized trial and adherence to PAP therapy for OSAH in women with HDP. Secondary objectives included assessment of PAP effects on 24-h BP, arterial stiffness, and maternal and fetal outcomes. Methods: Women with singleton pregnancies at ⩾12 weeks' gestation and hypertension underwent home level 2 polysomnography; those with mild to moderate OSAH (apnea-hypopnea index ⩾ 5 events/h; women with severe OSAH with apnea-hypopnea index > 30 events/h and oxygen desaturation index > 30 were excluded) were randomized to either PAP or nasal dilator strip (NDS; control) therapy. After PAP education, adherence was monitored online with episodic phone or in-person support by research personnel. Twenty-four-hour BP and arterial stiffness were assessed at baseline and before delivery. Maternal and fetal outcomes were also recorded. Results: Of 105 potentially eligible participants, 67 agreed to undergo screening for OSAH over 38 months; 48 women meeting OSAH inclusion criteria were randomized to PAP (n = 27) or NDS (n = 21) therapy. Of these, 14 PAP (52%) and 13 NDS (62%) participants completed all predelivery measurements, with lack of completion due to urgent delivery (19% in the PAP group, 14% in the NDS group), PAP intolerance at initiation (19%), or other factors. Mean PAP use was 3.1 ± 2.5 h/night, with use ⩾4 h/night on 38.4 ± 33.7% of nights during 9.6 ± 4.0 weeks of treatment. BP was controlled within the target range in most participants. There were no differences in mean change in 24-hour BP or arterial stiffness measurements or in adverse maternal and fetal outcomes between the PAP and NDS groups in either intention-to-treat or per-protocol analyses. Conclusions: PAP adherence was suboptimal in this HDP cohort despite education and troubleshooting. Further work is required to identify optimal OSAH treatment strategies during pregnancy. Clinical trial registered with www.clinicaltrials.gov (NCT03309826).

Symptoms of Posttraumatic Stress Disorder are Associated with Altered Glucose Parameters in Early and Late Gestation

OBJECTIVE

Posttraumatic stress disorder (PTSD) is associated with increased risk for insulin resistance and the development of diabetes outside of pregnancy. In pregnancy, emerging evidence suggests that PTSD is associated with increased risk for gestational diabetes; however, it is not yet known how PTSD is associated with disruptions in glucose processing across gestation. Therefore, the aim of the current study was to test associations between PTSD symptoms and glucose parameters in early and late gestation among pregnant people without a history of pregestational diabetes.

STUDY DESIGN

Two 34 participants were included in these analyses. PTSD symptoms were measured using the PTSD Checklist for DSM-5 (PCL-5) in early gestation. Fasting blood samples were collected at approximately 12 and 32 gestational weeks and were used to calculate β-cell function and insulin sensitivity.

RESULTS

Participants were 31 years old (standard deviation [SD] = 6) with body mass index (BMI) of 36 kg/m2 (SD = 7) at enrollment, 26% reported their ethnicity as Hispanic, 62% reported their race as White, 17% Black, 2% Asian, 3% Native American, 9% more than one race, and 11% unknown/not reported. Hierarchical linear regression analyses revealed that, after adjusting for several covariates including maternal age, race, ethnicity, BMI, apnea hypopnea index, and depressive symptoms, PTSD symptoms were positively associated with β-cell function in early (β = 0.230, p = 0.016) and late gestation (β = 0.238, p = 0.037).

CONCLUSION

Higher PTSD symptoms were associated with greater insulin secretion over pregnancy in this sample. More research is needed to replicate these findings and evaluate the effects of treatment of PTSD on mitigating the risk for gestational diabetes.

KEY POINTS

· We examined associations among symptoms of PTSD and glucose parameters over pregnancy.. · Symptoms of PTSD were positively associated with β-cell function over pregnancy.. · Symptoms of PTSD were not associated with insulin resistance over pregnancy..

Sleep disorders during pregnancy: an underestimated risk factor for gestational diabetes mellitus

Sleep disorders are highly prevalent during pregnancy and significantly affect women's health and quality of life. Gestational diabetes mellitus (GDM) is one of the most common metabolic complications during pregnancy and constitutes a significant risk factor for both mother and fetus in the short and the long term. While the association between sleep disorders and type 2 diabetes mellitus (T2DM) is indisputable, it is not clear whether there is a link between sleep disorders and GDM. The aim of this article was to investigate the association between sleep disorders and GDM and whether the treatment of sleep disorders may prevent GDM development. Insomnia, obstructive sleep apnea (OSA), restless legs syndrome (RLS), and narcolepsy were the most common sleep disorders identified during pregnancy and were related to poor sleep quality and short or prolonged sleep duration. They were all associated with an increased risk of GDM. The ideal sleep duration for pregnant women was determined at 8-9 h daily. In conclusion, sleep disorders constitute a risk factor for GDM. It is imperative that prospective studies be conducted to evaluate the effect of the early management of sleep disorders on GDM manifestation and control. Healthcare providers should highlight the importance of sufficient sleep to reinforce pregnancy outcomes.

A Relation between Obstructive Sleep Apnea in Pregnancy and Delivering Small for Gestational Age Infant-A Systematic Review

Obstructive sleep apnea (OSA) during pregnancy can negatively affect both the mother and the baby. Our main goal is to show whether there is an association between OSA during pregnancy and delivering small for gestational age (SGA) infants. This systematic review was conducted according to the PRISMA 2020 statement using three databases: MEDLINE via PubMed, Scopus, and Cochrane Library. All databases were last accessed on 1 June 2023. The implemented systematic literature search identified 744 articles. After excluding reviews, meta-analyses, book chapters, case reports, and letters, 47 studies were analyzed, 18 of which finally met the inclusion criteria. The included studies mainly indicate that OSA during pregnancy may not significantly impact SGA, but some of them have shown the existence of this relation. Nevertheless, it is recommended that all pregnant women should be screened for symptoms of OSA and that sleep tests should be performed on those who show signs of it. Detecting and treating OSA early in pregnancy can help reduce the condition's negative effects. However, more extensive studies are still needed to gather clear evidence on the impact of an OSA diagnosis on mothers and babies.

Increasing systemic chronic inflammation mediated the association between poor sleep during pregnancy and gestational cardiovascular health

OBJECTIVES

This study aimed to examine the association between sleep behaviors and cardiovascular health (CVH) during pregnancy and test whether high-sensitivity C-reactive protein (hs-CRP) mediates this association.

METHODS

The study included 4204 pregnant women from the Maternal and Infant Health cohort study in Hefei (MIH-Hefei). Information on sleep (chronotype, sleep duration, snoring, daytime sleepiness, and insomnia) was collected through a touch-screen structured questionnaire at 16-23 weeks' gestation. CVH (body mass index, blood pressure, total cholesterol, glucose, and smoking) and hs-CRP were measured at 24-28 weeks' gestation. The role of hs-CRP in the association between sleep and CVH was explored in a mediation analysis, while adjusting for multiple confounding factors.

RESULTS

Poor sleep score was significantly associated with poor gestational CVH metrics, including an RR of 0.872 (95% CI, 0.810, 0.938) for having all ideal (vs. any nonideal) CVH metrics; hs-CRP level was significantly associated with poor gestational CVH metrics, including an RR of 0.531 (95% CI, 0.432, 0.609) for having all ideal (vs. any nonideal) CVH metrics. Sleep scores were positively correlated with hs-CRP level (β, 0.020, 95% CI, 0.006, 0.034). Mediation analysis revealed that the association between sleep and CVH mediated by hs-CRP was 12.31% (indirect effect, -0.0095, 95% CI, -0.0167, -0.0042).

CONCLUSIONS

Poor sleep during pregnancy, particularly late chronotype and snoring, may worsen CVH by increasing systemic chronic inflammation.

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

The Society of Anesthesia and Sleep Medicine and the Society for Obstetric Anesthesia and Perinatology tasked an expert group to review existing evidence and to generate recommendations on the screening, diagnosis, and treatment of patients with obstructive sleep apnea during pregnancy. These recommendations are based on a systematic review of the available scientific evidence and expert opinion when scientific evidence is lacking. This guideline may not be appropriate for all clinical situations and patients, and physicians must decide whether these recommendations are appropriate for their patients on an individual basis. We recognize that not all pregnant people may identify as women. However, data on non-cisgendered pregnant patients are lacking, and many published studies use gender-binary terms; therefore, depending on the study referenced, we may refer to pregnant individuals as women. This guideline may inform the creation of clinical protocols by individual institutions that consider the unique considerations of their patient populations and the available resources.

Treatment of obstructive sleep apnea in high risk pregnancy: a multicenter randomized controlled trial

BACKGROUND

Obstructive sleep apnea (OSA) during pregnancy is a risk factor for preeclampsia possibly through a link to placental physiology. This study evaluates the efficacy of continuous positive airway pressure (CPAP) on the modulation of blood pressure and the reduction in preeclampsia in women with high-risk pregnancy and OSA.

METHODS

A multicenter open-label, randomized controlled trial comparing CPAP treatment versus usual antenatal care was conducted in three academic hospitals in Bangkok, Thailand. Participants included singleton pregnant women aged older than 18 years with any high-risk condition (i.e., chronic hypertension, obesity, history of preeclampsia or gestational diabetes in the previous pregnancy, or diabetes), and OSA (respiratory disturbance index 5-29.99 events/hour by polysomnography), who presented either in the first trimester (gestational age, GA 0-16 weeks) or subsequently developed OSA during the 2nd trimester (GA 24-28 weeks). The primary endpoint was blood pressure during antenatal care. Secondary endpoints included the incidence of preeclampsia. An intention-to-treat analysis was performed with additional per-protocol and counterfactual analyses for handling of nonadherence.

RESULTS

Of 340 participants, 96.5% were recruited during the first trimester. Thirty participants were later excluded leaving 153 and 157 participants in the CPAP and usual-care groups for the modified-intention-to-treat analysis. CPAP adherence rate was 32.7% with average use of 2.5 h/night. Overall, CPAP treatment significantly lowered diastolic blood pressure (DBP) by - 2.2 mmHg [95% CI (- 3.9, - 0.4), p = 0.014], representing approximately - 0.5 mmHg per hour of CPAP use [95%CI (- 0.89, - 0.10), p = 0.013]. CPAP treatment also altered the blood pressure trajectory by continuously lowering DBP throughout pregnancy with mean differences (95% CI) of - 3.09 (- 5.34, - 0.93), - 3.49 (- 5.67, - 1.31) and - 3.03 (- 5.20, - 0.85) mmHg at GA 18-20, 24-28, and 32-34 weeks, respectively compared to 0-16 weeks. Preeclampsia rate was 13.1% (20/153 participants) in the CPAP and 22.3% (35/157 participants) in the usual-care group with a risk difference (95% CI) of - 9% (- 18%, - 1%, p-value = 0.032) and a number-needed-to-treat (95% CI) of 11 (1, 21).

CONCLUSIONS

CPAP treatment in women with even mild-to-moderate OSA and high-risk pregnancy demonstrated reductions in both DBP and the incidence of preeclampsia. CPAP treatment also demonstrated a sustained reduction in DBP throughout gestation. Trial registration ClinicalTrial.GovNCT03356106, retrospectively registered November 29, 2017.

The effectiveness of continuous positive airway pressure for treating obstructive sleep apnoea in pregnancy: A systematic review

BACKGROUND

Obstructive sleep apnoea (OSA) occurs in 15-20% of pregnant women living with obesity. As global obesity prevalence increases, OSA in pregnancy is concurrently increasing, yet remains under-diagnosed. The effects of treating OSA in pregnancy are under-investigated.

AIM

A systematic review was conducted to determine whether treating pregnant women with OSA using continuous positive airway pressure (CPAP) will improve maternal or fetal outcomes, compared with no treatment or delayed treatment.

MATERIALS AND METHODS

Original studies in English published until May 2022 were included. Searches were conducted in Medline, PubMed, Scopus, the Cochrane Library and clinicaltrials.org. Maternal and neonatal outcome data were extracted, and quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach (PROSPERO registration: CRD42019127754).

RESULTS

Seven trials met inclusion criteria. Use of CPAP in pregnancy appears to be well tolerated with reasonable adherence. Use of CPAP in pregnancy may be associated with both a reduction in blood pressure and pre-eclampsia. Birthweight may be increased by maternal CPAP treatment, and preterm birth may be reduced by treatment with CPAP in pregnancy.

CONCLUSION

Treatment of OSA with CPAP in pregnancy may reduce hypertension and, preterm birth, and may increase neonatal birthweight. However, more rigorous definitive trial evidence is required to adequately assess the indication, efficacy, and applications of CPAP treatment in pregnancy.

A trial of positive airway pressure for the treatment of sleep apnea in pregnancy

BACKGROUND

The pathophysiology of obstructive sleep apnea in pregnancy remains poorly understood and studies examining the effect of treatment with positive airway pressure on pregnancy have been limited.

OBJECTIVE

This study aimed to perform a randomized controlled trial of positive airway pressure treatment for obstructive sleep apnea in pregnancy.

STUDY DESIGN

Participants with a body mass index ≥30 kg/m² underwent polysomnography at 14 to 20 weeks' gestation (visit 1) and those with obstructive sleep apnea (apnea-hypopnea index ≥5 but <50) were enrolled. In phase 1, participants were randomized to autotitrating positive airway pressure vs sham positive airway pressure; in phase 2, the sham arm was replaced with a sleep hygiene control. Participants returned at 28 to 31 weeks' gestation (visit 2). The mean arterial blood pressure, uterine artery Doppler pulsatility index, endoglin, soluble FMS-like tyrosine kinase 1 levels, and placental growth factor levels were measured, as well as fasting glucose and insulin to calculate insulin resistance (homeostatic model assessment for insulin resistance). The primary outcome was a composite of the uterine artery Doppler pulsatility index, soluble FMS-like tyrosine kinase 1 to placental growth factor ratio, and the homeostatic model assessment for insulin resistance. For secondary analyses, each outcome variable was analyzed independently. Adherence to treatment was examined.

RESULTS

A total of 241 participants completed visit 1, and 89 (37%) had an apnea-hypopnea index between 5 and 50. Of the those, 51 participants were randomized in phase 1 and 38 in phase 2. There was no significant difference in our primary outcome by treatment group. In secondary analyses, the uterine artery Doppler pulsatility index was lower in participants on autotitrating positive airway pressure when compared with sleep hygiene controls. Otherwise, there were no differences in the mean arterial blood pressure, angiogenic markers, or metabolic markers in phase 1, phase 2, or across the entire study. The overall adherence to autotitrating positive airway pressure therapy was low, but the mean use was greater in phase 2 (0.3±0.6 hours/night vs 1.3±2.3 hours/night; P=.10). For those on active therapy, fasting glucose values decreased as adherence increased.

CONCLUSION

This randomized controlled trial of autotitrating positive airway pressure in pregnancy did not find any differences in a composite primary cardiometabolic risk profile between the treatment groups. Higher autotitrating positive airway pressure adherence was associated with lower fasting glucose levels. The use of a sham positive airway pressure control arm in phase1 may have negatively impacted adherence to active treatment.

A randomized controlled trial of sleep study surveillance with targeted autoregulated positive airway pressure therapy for obstructive sleep apnea in pregnancy

BACKGROUND

Obstructive sleep apnea is associated with adverse pregnancy outcomes. The impact therapy for obstructive sleep apnea has on these pregnancy outcomes remains under investigated.

OBJECTIVE

This study aimed to determine the effects of targeted autoregulated positive airway pressure in women at risk of obstructive sleep apnea on adverse pregnancy outcomes, cost, and natural history of obstructive sleep apnea.

STUDY DESIGN

Pregnant women at high risk of obstructive sleep apnea were randomized to either a sleep study screening group receiving autoregulated positive airway therapy or a group not screened for obstructive sleep apnea receiving standard obstetrical care (control). Women in the sleep study-screened group received a sleep study at 2 periods during pregnancy, early (6-16 weeks of gestation) and late (27-33 weeks of gestation), with initiation of autoregulated positive airway therapy if their Apnea Hypopnea Index indicated ≥5 events per hour. Women of both groups had a sleep study 3 months after delivery. The primary outcome was effect on adverse pregnancy outcomes, a composite of hypertension, preterm birth, low birthweight, stillbirth, and diabetes mellitus. The secondary outcomes included obstructive sleep apnea severity and hospital costs.

RESULTS

Among 193 women randomized (100 in the sleep study-screened group and 93 in the control group; 6 lost to follow-up), there was no significant difference in composite adverse pregnancy outcomes (46.4% screened vs 43.3% control; P=.77), hypertension (23.7% screened vs 32.0% control; P=.25), preterm birth (13.4% screened vs 10.0% control; P=.5), low birthweight (5.2% screened vs 6.7% control; P=.76), stillbirth (1% screened vs 0% control; P=1), gestational diabetes (19.6% screened vs 13.3% control; P=.33), or mean cost ($12,185 screened vs $12,607 control). The Apnea Hypopnea Index increased throughout pregnancy, peaking at 3 months after delivery (P<.001). There were 24 subjects (25.8%) who had a new diagnosis of obstructive sleep apnea, with 6 in whom autoregulated positive airway was prescribed. The autoregulated positive airway compliance rates were poor with usage rates ranging from 2% (1 of 64 days) to 43% (6 of 14 days).

CONCLUSION

Targeted autoregulated positive airway therapy for obstructive sleep apnea did not decrease composite adverse pregnancy outcomes or hospital costs in the sleep study-screened high-risk pregnancy group compared with the group that received no obstructive sleep apnea screening. However, a small sample size, low autoregulated positive airway prescription rates, and poor compliance resulted in difficulty in drawing a definitive conclusion. The prevalence and severity of obstructive sleep apnea worsened throughout pregnancy, with the highest rates detected in the postpartum period. Large, multicenter clinical trials that are adequately powered are needed.

Association between sleep disordered breathing in early pregnancy and glucose metabolism

STUDY OBJECTIVES

To examine the association between maternal sleep disordered breathing (SDB) and glucose metabolism in early gestation.

METHODS

Women with body mass index (BMI) ≥27 kg/m2 and singleton pregnancies underwent in-home sleep study (HSAT) and homeostatic model assessment (HOMA) in early pregnancy. Insulin resistance (HOMA-IR) and β-cell function (HOMA %B) were derived. Exclusion criteria included pregestational diabetes, use of continuous positive airway pressure and chronic steroid therapy. We performed linear regression analyses to evaluate the association between continuous measures of SDB (respiratory event index (REI), and oxygen desaturation index (ODI)) and glucose metabolism parameters (HOMA-IR and HOMA %B). Analyses were adjusted for a set of a priori selected variables which included gestational age, maternal age, BMI, ethnicity, race, and parity.

RESULTS

One hundred and ninety-two pregnant women with median (interquartile range) BMI of 35.14 (8.30) kg/m2 underwent HSAT and HOMA assessment at 11.14 (3) and 15.35 (4.14) gestational weeks, respectively. REI and ODI, as continuous values, were associated with HOMA-IR after adjusting for covariates. OSA (obstructive sleep apnea) diagnosis (REI > 5 events per hour) was not associated with HOMA-IR after adjusting for BMI (p ≥ 0.05). None of the parameters were associated with HOMA %B (p > 0.07).

CONCLUSIONS

SDB and insulin resistance are associated in early pregnancy, with a dose response association between respiratory event index severity and insulin resistance. Further studies are needed to establish if pregnant women with overweight and obesity may benefit from early SDB screening to improve glucose metabolic outcome. Clinical trials: NCT02412696, Positive Airway Pressure, Sleep Apnea, and the Placenta (PAP-SAP) https://clinicaltrials.gov/ct2/show/NCT02412696?term=Bourjeily&draw=2&rank=2 and NCT02917876, Predictors of De-novo Development of Obstructive Sleep Apnea in Pregnancy (Predictors) https://clinicaltrials.gov/ct2/show/NCT02917876?term=Bourjeily&draw=2&rank=1.

Obstructive sleep apnea in pregnant women

The prevalence of OSA in the low-risk obstetric population is thought to be low; best estimates have been extrapolated from the one available large prospective study and likely range between 3–8%.1 OSA prevalence in high-risk pregnant women such as those with obesity and chronic hypertension is significantly higher as extrapolated from several smaller prospective studies which have reported a prevalence as high as 37% in obese women.2 –6 Despite the high prevalence of OSA in high-risk pregnant women, it remains underdiagnosed due to several factors.

An emerging body of literature suggests that OSA may also have serious implications for the health of mothers and fetuses during and beyond pregnancy, but there is still no data to determine if OSA treatment mitigates these adverse outcomes. In this review, we will examine this body of literature from the perspective of the anesthesiologist: the association between pregnancy and the development or worsening of OSA; OSA as it relates to adverse maternal and fetal outcomes; antepartum and screening considerations for OSA in pregnant women; and recommendations regarding the peripartum management of OSA.

A Review of the Associations Between Obstructive Sleep Apnea and Gestational Diabetes Mellitus and Possible Mechanisms of Disease

Obstructive sleep apnea (OSA) usually leads to the occurrence of diabetes. Gestational diabetes mellitus (GDM) is a common gestational complication associated with adverse maternal and fetal outcomes. Increasing studies suggest that women with OSA during pregnancy may be at a significantly greater risk of developing GDM. It is crucial to explore the association between OSA and GDM and the mechanisms underlying this association. In this review, we presented a comprehensive literature review of the following: the association between OSA and GDM, the possible mechanisms of this association, and the effects of continuous positive airway pressure (CPAP) on OSA with GDM. The results showed that most authors suggested that there was an association between OSA and GDM. The intermittent hypoxemia (IH) and reduction of slow-wave sleep (SWS) may be the key to this association. IH induces the products of oxidative stress and inflammation as well as dysregulation of the hypothalamic-pituitary-adrenal, which lead to diabetes. In addition, SWS reduction in OSA enhances the inflammation by increasing the inflammatory cytokines, increases the sympathetic activation, and causes changes in leptin level, which result in the development of GDM. Additionally, whether CPAP is beneficial to GDM remains still unclear.

The cardiovascular, metabolic, fetal and neonatal effects of CPAP use in pregnant women: a systematic review

Continuous positive airway pressure (CPAP) is the standard treatment for obstructive sleep apnea (OSA), but its outcomes for the pregnant are still undefined. This study aims to review current CPAP intervention during pregnancy, discuss published trials, and propose relevant issues that have yet to be addressed satisfactorily about the cardiovascular, metabolic, fetal, and neonatal effects of CPAP treatment during gestation. Two authors independently conducted a systematic review until March 28th, 2021 on PubMed, BVS, and Cochrane Library, using PRISMA guidelines, and risk of bias. Discrepancies were reconciled by a third reviewer. Of 59 identified citations, eight original trials have submitted a total of 90 pregnant women to polysomnography and CPAP therapy. Four studies performed in samples with hypertension or preeclampsia presented blood pressure decrease or maintained the antihypertensive drug dose in the CPAP group. After CPAP utilization, one trial registered cardiac output and stroke volume increase with heart rate and peripheral vascular resistance decrease, which were correlated with birth weight increment. Others documented a higher Apgar in the CPAP group and more fetal movements during CPAP use. There was a reduction in serum uric acid and tumor necrosis factor-alpha in the CPAP groups whose blood pressure decreased. However, two weeks of CPAP use in women with gestational diabetes and OSA did not improve glucose levels but raised the insulin secretion in those adherents to CPAP. Despite these positive results without adverse effects, randomized controlled trials with standardized follow-up in larger populations are required to determine CPAP therapy recommendations in pregnancy.

Obstructive Sleep Apnea Is Associated with Newly Diagnosed Gestational Diabetes Mellitus

Rationale: Sleep-disordered breathing (SDB) is associated with increased risk of adverse pregnancy outcomes, including gestational diabetes mellitus (GDM). GDM is a significant cause of maternal and infant morbidities. Assessing these risk factors concurrently may facilitate both the identification of women at GDM risk and the initiation of GDM prevention strategies.Objectives: To investigate whether SDB events, including SDB in rapid eye movement (REM) sleep and other sleep parameters, are associated with increased risk of GDM and to evaluate the performance of the models investigating associations between breathing and sleep parameters and GDM risk.Methods: In this case-control study, 46 women with newly diagnosed GDM and 46 healthy control subjects, who were individually matched for age, gestational age, body mass index, race, and parity, completed overnight polysomnographic studies and sleep questionnaires after being screened for GDM during the late-second to mid-third trimesters. Conditional logistic regression analysis was used to identify models investigating associations between risk factors and GDM risk. The Bayesian information criterion (BIC) was employed to compare models; the model with the lowest BIC is preferred.Results: Obstructive sleep apnea (OSA; defined as an apnea-hypopnea index [AHI] >5 events/h) was present in 22% of subjects with GDM and 9% of control subjects (P < 0.001). Women with OSA had a higher GDM risk (odds ratio [OR], 4.71; 95% confidence interval [CI], 1.05-21.04). In individual models, GDM risk was also significantly higher among women with higher overall AHI (events/h OR, 1.81; 95% CI, 1.01-3.27), higher AHI in REM (events/h OR, 2.09; 95% CI, 1.02-4.31), higher oxygen desaturation index greater than or equal to 4% (ODI4; events/h OR, 2.21; 95% CI, 1.03-4.73), and higher Sleep Apnea Symptom Score (OR, 2.72; 95% CI, 1.11-6.69). The percentage of non-REM sleep was significantly associated with decreased risk of GDM (percentage of non-REM sleep OR, 0.88; 95% CI, 0.78-0.99). The BIC supports the conclusion that there is a strong association between AHI in REM and GDM risk compared with the other significant models.Conclusions: SDB events, including REM-related OSA, are linked to increased GDM risk. GDM risk is also influenced by intercorrelated sleep variables.

Sleep Duration, Sleep Timing, and Sleep Disordered Breathing-Associations With Obesity and Gestational Diabetes in Pregnancy

Pregnant individuals may come into pregnancy with underlying sleep abnormalities but are also predisposed to developing sleep issues such as obstructive sleep apnea, due to the physiologic changes associated with the gravid state. This article will review the epidemiology of sleep duration, sleep timing, and sleep disordered breathing in pregnancy with a focus on how the prevalence of these sleep conditions relate to body mass index. In addition, it will summarize the literature suggesting a link between these sleep disturbances and an increased risk for gestational diabetes.

Is snoring during pregnancy a predictor of later life obstructive sleep apnoea? A case-control study

BACKGROUND

Obstructive sleep apnoea (OSA) appears common in pregnancy. Complications of pregnancy such as gestational diabetes and hypertension predispose women to cardiometabolic disease in later life. It is unknown if snoring during pregnancy is a risk marker for later-life OSA.

METHODS

We analysed data from N = 897 women in the Sleep Apnea Global Interdisciplinary Consortium (SAGIC), which recruited patients attending sleep clinics at 11 sites. There were 577 cases with current OSA and 320 controls. Cases were further categorised into mild, moderate, and severe OSA based on apnoea-hypopnoea index. Retrospective self-report of snoring during pregnancy was the exposure of interest and was reported by 2.9% of cases and 3.4% of controls.

RESULTS

Multinomial regression demonstrated that snoring during a previous pregnancy was not significantly associated with mild (OR 0.34, 95% CI 0.09-1.25, p = 0.10), moderate (OR 0.69, 95% CI 0.21-2.19, p = 0.52), or severe OSA (OR 1.86, 95% CI 0.77-4.48, p = 0.17) compared to no snoring during pregnancy. Results were unchanged after adjustment for age, body mass index, and ethnicity. 79% of women reported current snoring but all who snored during pregnancy reported current snoring.

CONCLUSIONS

Women who snore during pregnancy continue snoring in later-life but do not appear more likely to develop OSA. These findings are limited by self-reported data, recall bias, and small numbers of women who reported snoring during pregnancy. A prospective study with objective measurement of sleep and snoring during pregnancy is needed to examine the links between sleep disorders in pregnancy with health in later life.

Sleep disordered breathing in pregnancy: A review of the pathophysiology of adverse pregnancy outcomes

Sleep disordered breathing (SDB) is a common obesity-related co-morbidity with strong associations to cardiometabolic disease. The risk of SDB is increased during pregnancy, particularly among obese pregnant women. Accumulating evidence suggests that an association exists between maternal SDB and the development of adverse pregnancy outcomes, particularly gestational diabetes and hypertensive disorders of pregnancy. Intermittent hypoxia, a central characteristic of SDB, has been shown in animal and clinical studies to dysregulate several biological pathways. This includes the promotion of oxidative stress, increased inflammation, activation of the hypothalamic-pituitary-adrenal axis, increased sympathetic activity and impaired glucose and insulin metabolism. This review considers how, during pregnancy, these pathophysiological processes are plausible mechanisms through which SDB may contribute to an increased risk of adverse outcomes, for the mother and perhaps also the offspring. However, a lack of robust evidence specific to the pregnant population, including limited evaluation of the placental function in affected pregnancies, limits our ability to draw definite conclusions on mechanisms contributing to adverse pregnancy outcomes and, indeed, the strength of association between SDB and certain pregnancy complications.

Sleep and sleep disorders in pregnancy

Pregnancy is associated with a number of physiologic changes in the body including hormonal, anatomical, and mechanical. These changes alter many physiologic functions including sleep. The literature suggests that a number of women develop changes in duration, pattern, and quality of sleep during pregnancy. In addition, these changes also pave the way for expression of sleep disorders (e.g., insomnia, obstructive sleep apnea, and restless legs syndrome). Change in sleep and appearance of sleep disorders not only influence pregnant women, but also have negative influences on the fetus and outcomes of pregnancy. However, optimal management of these disorders may reverse adverse consequences. In this chapter, risk factors, clinical presentation, and management of insomnia, obstructive sleep apnea, and restless legs syndrome during pregnancy are discussed in view of the available literature.

A Clinical Perspective of Sleep and Andrological Health: Assessment, Treatment Considerations, and Future Research

CONTEXT

Sleep that is insufficient, misaligned, or disrupted causes hypersomnolence and neuropsychological deficits, adversely affects cardiometabolic health, and is increasingly recognized to impair other biological processes that lead to conditions important to men, such as hypogonadism, erectile dysfunction, and infertility.

EVIDENCE ACQUISITION

Literature review from 1970 to December 2018.

EVIDENCE SYNTHESIS

High-quality and complementary epidemiological and interventional studies establish that abnormal sleep is associated with increased mortality, hypertension, and other cardiometabolic disorders (insufficient, disrupted, and misaligned sleep), as well as reduced fecundity and total sperm count (insufficient sleep), erectile dysfunction (disrupted sleep), and low testosterone (both). Circadian misalignment shifts the peak of testosterone's diurnal rhythm to occur soon after waking up, irrespective of the biological clock time, but it does not change the mean concentration. Preliminary studies show that extending sleep in individuals who are chronically sleep deprived may become a strategy to reduce insulin resistance and hypertension. Continuous positive airway pressure therapy can improve erectile function, and possibly systemic testosterone exposure, but only when used adherently by men with obstructive sleep apnea. Both high-dose and replacement-dose testosterone therapies modestly worsen sleep-disordered breathing, but they also improve cardiometabolic function and sexual desire. Persistence of either the adverse or beneficial outcomes over the longer term requires further investigation.

CONCLUSIONS

Sleep is increasingly recognized to be essential for healthy living. Establishing the effect of abnormal sleep, and of improving sleep, on andrological issues of prime interest to men will promote prioritization of sleep, and may thereby improve overall long-term health outcomes.

A Screening Algorithm for Obstructive Sleep Apnea in Pregnancy

Rationale: Obstructive sleep apnea (OSA) is common in pregnancy and associated with maternal and fetal complications. Early detection of OSA may have important implications for maternal-fetal well-being. A screening tool combining several methods of assessment may better predict OSA among pregnant women compared with tools that rely solely on self-reported information.Objectives: To develop a screening tool combining subjective and objective measures to predict OSA in pregnant women.Methods: This study is a secondary analysis using data collected from a completed cohort of pregnant women (n = 121 during the first and n = 87 during the third trimester). Participants underwent full polysomnography and completed the Multivariable Apnea Prediction Questionnaire. The Obstructive Sleep Apnea/Hypopnea Syndrome Score and Facco apnea predictive model were obtained. Logistic regression analysis and area under the curve (AUC) were used to identify models predicting OSA risk.Results: Participants' mean age was 27.4 ± 7.0 years. The prevalence of OSA during the first and third trimester was 10.7% and 24.1%, respectively. The final model predicting OSA risk consisted of body mass index, age, and presence of tongue enlargement. During the first trimester, the AUC was 0.86 (95% confidence interval [CI], 0.76-0.96). During the third trimester, the AUC was 0.87 (95% CI, 0.77-0.96). When the first-trimester data were used to predict third-trimester OSA risk, the AUC was 0.87 (95% CI, 0.77-0.97). This model had high sensitivity and specificity when used during both trimesters. The negative posttest probabilities (probability of OSA given a negative test result) ranged from 0.03 to 0.07.Conclusions: A new model consisting of body mass index, age, and presence of tongue enlargement provided accurate screening of OSA in pregnant women, particularly African-Americans. This tool can be easily and rapidly administered in busy clinical practices without depending on patients' awareness of experiencing apnea symptoms.

Management of Preexisting Diabetes in Pregnancy: A Review

IMPORTANCE

The presence of preexisting type 1 or type 2 diabetes in pregnancy increases the risk of adverse maternal and neonatal outcomes, such as preeclampsia, cesarean delivery, preterm delivery, macrosomia, and congenital defects. Approximately 0.9% of the 4 million births in the United States annually are complicated by preexisting diabetes.

OBSERVATIONS

Women with diabetes have increased risk for adverse maternal and neonatal outcomes, and similar risks are present with type 1 and type 2 diabetes. Both forms of diabetes require similar intensity of diabetes care. Preconception planning is very important to avoid unintended pregnancies and to minimize risk of congenital defects. Hemoglobin A1c goals are less than 6.5% at conception and less than 6.0% during pregnancy. It is also critical to screen for and manage comorbid illnesses, such as retinopathy and nephropathy. Medications known to be unsafe in pregnancy, such as angiotensin-converting enzyme inhibitors and statins, should be discontinued. Women with obesity should be screened for obstructive sleep apnea, which is often undiagnosed and can result in poor outcomes. Blood pressure goals must be considered carefully because lower treatment thresholds may be required for women with nephropathy. During pregnancy, continuous glucose monitoring can improve glycemic control and neonatal outcomes in women with type 1 diabetes. Insulin is first-line therapy for all women with preexisting diabetes; injections and insulin pump therapy are both effective approaches. Rates of severe hypoglycemia are increased during pregnancy; therefore, glucagon should be available to the patient and close contacts should be trained in its use. Low-dose aspirin is recommended soon after 12 weeks' gestation to minimize the risk of preeclampsia. The importance of discussing long-acting reversible contraception before and after pregnancy, to allow for appropriate preconception planning, cannot be overstated.

CONCLUSIONS AND RELEVANCE

Preexisting diabetes in pregnancy is complex and is associated with significant maternal and neonatal risk. Optimization of glycemic control, medication regimens, and careful attention to comorbid conditions can help mitigate these risks and ensure quality diabetes care before, during, and after pregnancy.

Metabolic Consequences of Obstructive Sleep Apnea Especially Pertaining to Diabetes Mellitus and Insulin Sensitivity

Obstructive sleep apnea (OSA) and diabetes has been known to be closely related to each other and both diseases impact highly on the public health. There are many evidence of reports that OSA is associated with diabetes with a bidirectional correlation. A possible causal mechanism of OSA to diabetes is intermittent hypoxemia and diabetes to OSA is microvascular complication. However, OSA and diabetes have a high prevalence rate in public and shares the common overlap characteristic and risk factors such as age, obesity, and metabolic syndrome that make it difficult to establish the exact pathophysiologic mechanism between them. In addition, studies demonstrating that treatment of OSA may help prevent diabetes or improve glycemic control have not shown convincing result but have become a great field of interest research. This review outlines the bidirectional correlation between OSA and diabetes and explore the pathophysiologic mechanisms by approaching their basic etiologies.

Pregnant pause: should we screen for sleep disordered breathing in pregnancy?

Physiological and hormonal changes in pregnancy can contribute towards sleep disordered breathing in pregnant women (SDBP). When present, SDBP increases the risk of several adverse maternal and fetal outcomes independent of factors such as age, weight and pre-existing maternal comorbidities. SDBP is underdiagnosed and may be hard to recognise because the presentation can be difficult to differentiate from normal pregnancy and the severity may change over the course of gestation. Timely intervention seems likely to help reduce adverse outcomes, but the relative benefits of intervention are still unclear. The definition of what constitutes a sleep-related breathing “disorder” in pregnancy may be different to the general population and so traditional thresholds for intervention may not be relevant in pregnancy. Any modifications to the disease definition in this group, or implementation of more intensive screening, may result in overdiagnosis. Further research is needed to help clinicians evaluate the balance of benefits and harms in this process. Until this is clearer there is a strong imperative for shared decision making in screening and treatment decisions, and screening programmes should be monitored to assess whether improved outcomes can be achieved at the healthcare system level.

Untreated sleep disordered breathing in pregnancy poses risks to maternal and fetal wellbeing, but thresholds for and effectiveness of intervention are unclear. Clinicians should use shared decision making for screening and treatment decisions.http://ow.ly/N0oN30noWnx

Sleep disorders in pregnancy

Anatomical, physiological, psychological and hormonal alterations affect sleep during pregnancy. Sleep appears tobe commonly impaired only after the first trimester. Albeit objective data regarding the reduction of sleep durationand efficiency are not univocal, poor sleep is reported by over half of pregnant women. The reasons underlyingthese complaints are multiple, including lower back pain, gastroesophageal reflux disorder (GERD), increasedmicturition and repositioning difficulties at night. Specific primary sleep disorders whose prevalence drasticallyincreases during pregnancy include obstructive sleep apnea (OSA) and restless legs syndrome (RLS), both relatedto gestational hypertension and gestational diabetes mellitus (GDM). Pre-eclampsia and labor complicationsleading to an increased number of cesarean sections and preterm births correlate with insomnia and OSA inparticular. Post-partum depression (PPD) and impairment of the mother-infant relationship may also be consideredas secondary effects deriving from poor sleep during pregnancy. Recognition and treatment of sleep disordersshould be encouraged in order to protect maternal and fetal health and prevent dire consequences at birth.

Obstructive sleep apnea in pregnancy: performance of a rapid screening tool

PURPOSE

The Sleep Apnea Symptom Score (SASS) has been commonly used to assess obstructive sleep apnea (OSA). The aim of this study was to examine the psychometric properties of the SASS and the predictive value of SASS incorporating bedpartner-reported information in identifying OSA in pregnant women.

METHODS

A cohort of healthy pregnant women completed the SASS and Pittsburgh Sleep Quality Index. Participants underwent overnight laboratory polysomnography (PSG) monitoring. Reliability and validity of the SASS were evaluated. A multivariable predictive model, incorporating the SASS score along with BMI, age, and bedpartner-reported information, was developed to assess the risk for OSA (AHI ≥ 5 events/h). Receiver operating characteristic curves for OSA were constructed to evaluate the sensitivity and specificity of the predictive model.

RESULTS

A total of 126 and 105 participants completed the PSG during the first and third trimester, respectively. The SASS demonstrated adequate validity and acceptable reliability (Cronbach's α = 0.72 during the third trimester). When the combined model consisting of SASS, age, BMI, and bedpartner-reported information was used, the area under the curve for AHI ≥ 5 for the first and third trimester was 0.781 (95%CI 0.648, 0.914) and 0.842 (95%CI 0.732, 0.952), respectively; the sensitivity/specificity was 76.9%/72.4% and 82.4%/78.0%, respectively.

CONCLUSIONS

The SASS alone has acceptable reliability and validity, but limited predictive values. A new tool, combining the SASS and other patient characteristics (i.e., age, BMI, and bedpartner-reported snoring and breathing pauses), demonstrated improved sensitivity and specificity, and thus may have greater utility in clinical practice for predicting OSA in pregnant women.

A Pilot Randomized-Controlled Trial on the Effect of CPAP Treatment on Glycemic Control in Gestational Diabetes: Study Design and Methods

Background: Gestational diabetes (GDM) is associated with adverse short- and long-term maternal and fetal outcomes. Observational data support a link between sleep-disordered breathing (SDB) during pregnancy and GDM. However, it is unknown whether treatment of SDB with continuous positive airway pressure (CPAP) improves glucose control in this patient population. In addition, CPAP adherence and feasibility as a treatment option in pregnancy is unknown. This pilot randomized, controlled trial aims to primarily determine the feasibility of CPAP treatment in pregnant women with SDB and GDM. This study is also investigating the effect of SDB treatment on 24-h glucose profiles as an exploratory outcome. Objectives: To describe the study methodology in this ongoing study of pregnant women with GDM and SDB. Patients and Methods: Pregnant women with GDM and SDB defined by apnea-hypopnea index (AHI) ≥10 (Chicago Scoring Criteria) on level 2 polysomnography are randomized to either auto titrating CPAP (experimental group) or a nasal dilator strip (control group) until delivery. The primary outcome, objectively-assessed adherence to CPAP, is measured over the course of the treatment period using device-specific software. Recruitment and retention rates will be calculated to assess the feasibility for planning future trials. Twenty-four hour glucose profiles are measured over a 72-h period using the continuous glucose monitoring (CGM) system, before and after the intervention. Conclusion: The results of this study will be highly informative to determine whether CPAP is a feasible treatment for pregnant women with GDM and SDB, a specialized population at risk for substantial comorbidity. The trial results will ultimately be useful in planning future SDB treatment trials in pregnancy and GDM. The study is registered on clinicaltrials.gov (NCT02245659).