Preventing postpartum insomnia: findings from a three-arm randomized-controlled trial of cognitive behavioral therapy for insomnia, a responsive bassinet, and sleep hygiene.

STUDY OBJECTIVES: Insomnia symptoms are common during the perinatal period and are linked to adverse outcomes. This single-blind three-arm randomized-controlled trial examined whether two interventions targeting different mechanisms prevent postpartum insomnia. METHODS: Participants were nulliparous females 26-32 weeks gestation with Insomnia Severity Index (ISI) scores ≥ 8, recruited in Australia and randomized 1:1:1 to: (1) a responsive bassinet (RB) designed to support infant sleep and reduce maternal sleep disruption until 6 months postpartum, (2) therapist-assisted cognitive behavioral therapy for insomnia (CBT-I) delivered during pregnancy and postpartum, or (3) a sleep hygiene booklet (control; CTRL). Outcomes were assessed at baseline (T1), 35-36 weeks gestation (T2), and 2, 6, and 12 months postpartum (T3-T5). The primary outcome was ISI scores averaged T3-T5. Primary analyses were regressions controlling for baseline outcomes. RESULTS: One hundred and twenty-seven participants (age M ± SD = 32.62 ± 3.49) were randomized (RB = 44, CBT-I = 42, CTRL = 41). Both interventions were feasible and well-accepted, with few related adverse events reported. Compared to CTRL, the average ISI across T3-T5 was lower for CBT-I (p = .014, effect size [ES] = 0.56, medium) but not RB (p = .270, ES = 0.25, small). Exploratory findings on maternal insomnia diagnosis, sleep disturbance, sleep-related impairment, beliefs and attitudes about sleep, depression, anxiety, as well as infant sleep outcomes were also presented. CONCLUSIONS: CBT-I but not RB reduced prenatal insomnia (very large effect) and prevented postpartum insomnia (medium effect). Further research is needed to examine the effects of both CBT-I and RB on other outcomes such as sleep-related well-being, postpartum depression, and maternal postpartum sleep duration. CLINICAL TRIAL REGISTRATION: The Study for Mother-Infant Sleep (The SMILE Project): reducing postpartum insomnia using an infant sleep intervention and a maternal sleep intervention in first-time mothers. https://www.anzctr.org.au/Trial/Registration/TrialReview.aspx?id=377927, Australian New Zealand Clinical Trials Registry: ACTRN12619001166167.