Risk of pre-term birth as a function of sleep quality and obesity: prospective analysis in a large Prematurity Research Cohort

Siobhan Sutcliffe; Peinan Zhao; Luisa Klaus Pilz; Megan Oakes; Antonina I Frolova; Erik D Herzog; Sarah K England

doi:10.1093/sleepadvances/zpad043

Risk of pre-term birth as a function of sleep quality and obesity: prospective analysis in a large Prematurity Research Cohort

Sleep Adv. 2023 Nov 2;4(1):zpad043. doi: 10.1093/sleepadvances/zpad043. eCollection 2023.

Authors

Siobhan Sutcliffe¹, Peinan Zhao², Luisa Klaus Pilz^{3

4}, Megan Oakes⁵, Antonina I Frolova⁶, Erik D Herzog⁷, Sarah K England⁸

Affiliations

¹ Division of Public Health Sciences, Department of Surgery; Alvin J. Siteman Cancer Center; and the Department of Obstetrics and Gynecology; School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
² Division of Clinical Research, Department of Obstetrics and Gynecology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
³ Department of Anesthesiology and Intensive Care Medicine and the Experimental and Clinical Research Center, Charite Universitatsmedizin Berlin, Berlin, Germany.
⁴ Corporate member of Freie Universität Berlin and Humboldt Universität zu Berlin, Berlin, Germany.
⁵ Department of Obstetrics and Gynecology, MemorialCare Miller Children's and Women's Hospital, Long Beach, CA, USA.
⁶ Division of Maternal-Fetal Medicine and Ultrasound, Department of Obstetrics and Gynecology, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.
⁷ Department of Biology, Washington University in St. Louis, St. Louis, MO, USA.
⁸ Department of Obstetrics and Gynecology, Center for Reproductive Health Sciences, School of Medicine, Washington University in St. Louis, St. Louis, MO, USA.

Abstract

Study objective: To investigate whether poor sleep quality is associated with pre-term birth (PTB) risk, overall and independent of sleep apnea and habitual snoring.

Methods: We used longitudinal data from the Washington University Prematurity Research Cohort to investigate the association between poor sleep quality (defined as a Pittsburgh Sleep Quality Index > 5) and PTB, overall and independent of sleep apnea and snoring (defined by the Berlin questionnaire and prior sleep clinic attendance). Associations were investigated for sleep quality early and throughout pregnancy. Stratified analyses were performed by factors previously shown to modify associations between sleep and PTB (race, pre-pregnancy obesity).

Results: Of the 976 eligible participants, 50.1% experienced poor sleep quality early in pregnancy (<20 completed weeks) and 14.2% delivered pre-term (n = 50 without and 89 with poor sleep quality). In multivariable-adjusted analyses, poor sleep quality early in pregnancy was associated with increased PTB risk (hazard ratio [HR] = 1.48, 95% confidence interval [CI] = 1.02-2.14). This association persisted after further adjustment for sleep apnea and snoring (HR = 1.50, 95% CI = 1.02-2.20) and in analyses stratified by race. It varied, however, by pre-pregnancy obesity. Among individuals without obesity, no association was observed between poor sleep and PTB (HR = 1.08, 95% CI = 0.65-1.79), whereas among those with obesity, a positive association was observed (HR = 2.94, 95% CI = 1.52-5.69, p-interaction = .05). This association was limited to individuals with obesity who experienced poor sleep both earlier and later in pregnancy (HR = 3.94, 95% CI = 1.56-9.99).

Conclusion: Our findings suggest that improving sleep quality early in pregnancy may be important for PTB prevention, particularly among individuals with obesity.

Keywords: cohort study; obesity; pregnancy; sleep.