Abstract

We completed a video-based, four-night, in-home, level 3 sleep apnea study of healthy, low-risk pregnant participants and their bed partners in order to characterize sleep physiology in the third trimester of pregnancy. Demographic, anthropometric, and baseline sleep health characteristics were recorded, and the NightOwl™ home sleep apnea test device was used to measure sleep breathing, posture, and architecture parameters. Symptoms of restless legs syndrome were elicited in the exit interview. Forty-one pregnant participants and 36 bed partners completed the study. Bed partners had a significantly higher prevalence of sleep apnea than their pregnant co-sleepers (31% vs. 5.9%). Bed partners also had more severe sleep apnea than their pregnant co-sleepers, and this persisted on an adjusted analysis for baseline differences in factors known to increase risk of sleep apnea. In pregnant participants, increasing gestational age was found to be protective against mild respiratory events but not more severe events. While the correlation between STOP-Bang score and measures of sleep apnea severity was weak, an affirmative response to the “witnessed apneas” item on the STOP-Bang questionnaire was a strong predictor of more severe sleep apnea for all participants. Smoking history also increased sleep apnea risk. Pregnant participants had lower sleep efficiency and longer self-reported sleep onset latency. Restless legs syndrome was experienced by 39.5% of the pregnant participants but no bed partners. From a sleep breathing perspective, people with healthy, low-risk pregnancies have better sleep than their bed partners despite lower sleep efficiency and higher rates of restless legs syndrome.

Statement of Significance Pregnancy negatively impacts sleep, and poor sleep in pregnancy negatively impacts maternal and fetal health. Pregnancy represents a unique challenge to sleep breathing physiology and, thus, an opportunity to test for sleep apnea. Sleep apnea however, while increased in pregnancy, is more common in males. This novel study tested healthy people with low-risk pregnancies and their bed partners for sleep apnea in the comfort of their home over four nights in late pregnancy. Sleep apnea was more common and worse in the bed partners. Advancing gestational age was protective against mild but not severe sleep apnea, and a critical remaining knowledge gap is this interplay in high-risk pregnancies. Future sleep in pregnancy research should make efforts to include high-risk pregnancies.

Competing Interest Statement

Dr. Kember is the President, CEO and majority shareholder of Shiphrah Biomedical (SBI), which is a research-based medical device company specializing in sleep during pregnancy. Dr. Kember receives no financial or material benefit for his roles at SBI. Dr. Kember and Dr. Warland are listed as an inventor on a patent-pending positional therapy device for use during sleep in pregnancy. Ms. Ritchie, Dr. Zia, Dr. Elangainesan, Dr. Gilad, Dr. Taati, Dr. Dolatabadi, and Dr. Hobson report no financial or non-financial conflicts of interest.

Funding Statement

This study was funded by Mitacs through the Mitacs E-Accelerate Program (Grant No. IT26655). The Mitacs Entrepreneur-Accelerate Program funds student and postdoctoral entrepreneurs to further develop the research or technology at the core of their start-up business by way of internships in collaboration with a university, professor and approved incubator. In this study, the total study funding was $30,000 CAD and was provided through Mitacs to the university (University of Toronto) for the professor (Author ED) to administer for the student/intern/entrepreneur (Author AJK) and the study expenses related to the company's (Shiphrah Biomedical Inc.; SBI) technology under the supervision of the incubator (Health Innovation Hub). Mitacs provided 50% of the study funding. Mitacs' contribution to the grant was matched by SBI, which provided the remaining 50% plus Ontario Harmonized Sales Tax (13% of $30,000). Mitacs had no role in the study design; collection, analysis and interpretation of data; in the writing of the report; and in the decision to submit the article for publication data. However, SBI with the oversight of the University of Toronto had a role in all these aspects via Author's AJK and ED.

Author Declarations

I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained.

Yes

The details of the IRB/oversight body that provided approval or exemption for the research described are given below:

This study was conducted in accordance with The Tri-Council Policy Statement: Ethical Conduct for Research Involving Humans and was approved by the University of Toronto Health Sciences Research Ethics Board (Protocol No. 41612).

I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals.

Yes

I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance).

Yes

I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable.

Yes

Data Availability

Study data are available upon reasonable request made to the corresponding author.

List of AbbreviationsAHIApnea hypopnea indexBMIBody mass indexHSATHome sleep apnea testingODIOxygen desaturation indexODI3Oxygen desaturation index using a 3% or more drop in peripheral blood oxygen saturation as the threshold for an event to be countedODI4Oxygen desaturation index using a 4% or more drop in peripheral blood oxygen saturation as the threshold for an event to be countedOSAObstructive sleep apneapAHIPeripheral arterial tone derived apnea hypopnea indexpAHI3Peripheral arterial tonometry-based apnea hypopnea index using a 3% or more drop in peripheral blood oxygen saturation as the threshold for an event to be countedpAHI4Peripheral arterial tonometry-based apnea hypopnea index using a 4% or more drop in peripheral blood oxygen saturation as the threshold for an event to be countedPATPeripheral arterial tonePRPulse ratePSGPolysomnographyRERespiratory eventsREMRapid eye movementRLSRestless legs syndromeSRSelf-reportedSLeeP AID4 StudySleep in Late Pregnancy: Artificial Intelligence Development for the Detection of Disturbances and Disorders StudySpO2Peripheral blood oxygen saturationSSStatistically significantTSTTotal sleep time