Birth outcomes for women with pre-existing mental health problems: a systematic review and meta-analysis

Clinical Snapshot

Key Findings

• P Value: Not reported in abstract but CIs suggest p<0.05 for all significant associations

• Effect Size: Adjusted OR for preterm birth: 1.41 (95% CI 1.27-1.56); Low birth weight: 1.28 (95% CI 1.22-1.33)

• Primary Outcome: Preterm birth, low birth weight, small for gestational age, and neonatal unit admission all significantly increased

• Nnt Or Sensitivity: Based on adjusted ORs, approximately 41% increased odds of preterm birth and 28% increased odds of low birth weight

• Confidence Interval: All confidence intervals exclude 1.0, indicating statistical significance

Clinical Application

Highly feasible - requires enhanced screening and care coordination already within existing maternity care frameworks Directly applicable to Australian practice; supports RACGP guidelines on mental health in pregnancy and aligns with National Maternity Services Plan priorities for vulnerable populations All pregnant women with pre-existing mental health conditions in Australian maternity care settings

Abstract

OBJECTIVES: To synthesise evidence on the association between any diagnosed or self-reported mental health problems prior to pregnancy (pre-existing mental health problems) and birth outcomes including preterm birth (PTB), low birth weight (LBW), small for gestational age (SGA), neonatal unit (NNU) admission and mode of birth (instrumental birth, planned or unplanned caesarean section). METHODS: Systematic searches were conducted in MEDLINE, CINAHL, Embase and PsycINFO in December 2024 for studies examining the association between any pre-existing mental health problems and PTB, LBW, SGA, NNU admission and mode of birth. Only articles published in English were included with no restriction on year of publication. Two reviewers independently screened studies and extracted data. Study quality was assessed using the Newcastle-Ottawa Scale and Joanna Briggs Institute checklists. Random-effects meta-analyses were conducted to pool crude and adjusted ORs (aORs) and risk ratios (aRR) with 95% CIs. ORs and RRs were analysed separately. Between-study heterogeneity was quantified using the I2 statistic. RESULTS: Of 15 467 records screened, 33 studies met the inclusion criteria. Women with any pre-existing mental health problems had higher odds and risks of adverse birth outcomes, including PTB (aOR 1.41, 95% CI 1.27 to 1.56) (aRR 1.36, 95% CI 1.21 to 1.51), LBW (aOR 1.28, 95% CI 1.22 to 1.33) (aRR 1.32, 95% CI 1.04 to 1.68), SGA (aOR 1.27, 95% CI 1.07 to 1.51) (aRR 1.34, 95% CI 1.19 to 1.51) and NNU admission (aOR 1.44, 95% CI 1.19 to 1.74). Adjusted estimates were based on multivariable models that commonly controlled for maternal age, parity and socio-demographic factors. No consistent associations were observed between pre-existing mental health problems and mode of birth. CONCLUSIONS: Pre-existing mental health problems were associated with increased risks and odds of several adverse birth outcomes. These findings highlight the importance of early identification and targeted support for women with mental health problems before pregnancy to strengthen preconception and maternity care planning. PROSPERO REGISTRATION NUMBER: CRD42023485834.

References

1. 1.Gong, J., Henderson, I., Lynch, R., Daskalopoulou, Z., Roberts, N., Fellmeth, G., Harrison, S., Quigley, M. A., & Alderdice, F. (2026). Birth outcomes for women with pre-existing mental health problems: a systematic review and meta-analysis. BMJ Open. https://doi.org/10.1136/bmjopen-2025-106566