Background: Cognitive behavioral therapy for insomnia (CBT-I) as a first-line treatment may improve insomnia in pregnant women. The efficacy of the components, modalities, doses, and effectiveness of CBT-I in pregnant women at follow-up remains unclear.

Objectives: To assess the effectiveness of CBT-I in pregnant women and identify effective intervention components, modalities, and doses.

Design: Systematic review and meta-analysis.

Methods: Six English databases (PubMed, Embase, Cochrane Library, Web of Science, PsycINFO, CINAHL) and four Chinese databases (CNKI, WanFang Data, SinoMed, and CQVIP) were searched from inception to 10 January 2023. Randomized controlled trials (RCTs) on CBT-I in pregnant women with outcomes of insomnia severity measured by Insomnia Severity Index (ISI) or sleep quality measured by Pittsburgh Sleep Quality Index (PSQI). Two reviewers independently completed records selection, data extraction, and study quality assessment. The fixed-effect or random-effect model was used for pooled analyses. Subgroup analyses were conducted based on different delivery types and intervention duration. The GRADE approach was used to evaluate the certainty of the evidence. Narrative analyses were used when meta-analysis was not appropriate. Mean differences with 95% CIs of insomnia severity and sleep quality scores were the main outcomes (greater scores indicating greater severity).

Results: Nine RCTs (N = 978) meeting the inclusion criteria were included. These trials included individual- (n = 6) or group-based (n = 3) interventions, which were conducted via face-to-face (n = 5), digital (n = 3) or telephone and e-mail (n = 1) formats. Six studies stated intervention components specific to pregnant women. CBT-I improved insomnia severity (MD = -2.69, 95% CI: -3.41 to -1.96, P ＜ 0.001, high quality evidence; MD = -3.69, 95% CI: -5.91 to -1.47, P = 0.001, moderate quality evidence) and sleep quality (MD = -2.85, 95% CI: -4.73 to -0.97, P = 0.003, moderate quality evidence; MD = -1.88, 95% CI: -2.89 to -0.88, P ＜ 0.001, moderate quality evidence) immediately after intervention (＜1-month) and at short-term (≥1 month to ＜6 months) follow-up, respectively. Two RCTs reported no effectiveness on insomnia severity at medium-term (≥6 months to＜12 months) follow-up. Only 1 RCT showed reduced insomnia severity at long-term (≥12 months) follow-up. One RCT reported no effectiveness in sleep quality at medium-term follow-up and effectiveness at long-term follow-up was not reported.

Conclusions: Pregnant women may benefit from CBT-I to improve short-term insomnia, but long-term effectiveness is unclear. Rigorous RCTs with long-term follow-ups are warranted.