Length of Maternity Leave Impact on Mental and Physical Health of Mothers and Infants, a Systematic Review and Meta-analysis

BackgroundRecent legislative decisions in the United States have encouraged discussion about national parental leave programs. Currently, over 47% of the United States workforce is female. However, the United States is the only nation of the 37 member countries in the Organization for Economic Co-Operation and Development (OECD) to have no national requirement for maternity leave. The first few months of a child's life are vital to their physical and mental development. Likewise, a gradual return to pre-partum functioning is important for a newly postpartum woman. While it has been shown that maternity leave positively impacts various measures of maternal and infant mental and physical health, we lack consensus on the optimal length of paid or unpaid maternity leave. Accordingly, we conducted a systematic review and meta-analysis to evaluate the optimal length of paid or unpaid maternity leave to encourage maternal and infant mental and physical health in the United States. Methods A systematic review and meta-analysis were conducted to synthesize and critically evaluate the current research investigating the association between maternity leave and maternal and infant mental and physical health using the Preferred Reporting in Systematic Reviews and Meta-Analyses guidelines. Databases EMBASE, PsycInfo, and PubMed were searched using specific inclusion and exclusion criteria. Methodological Index for Non-Randomized Studies scale assessed the methodological quality of the included eligible studies. The magnitude of heterogeneity between-study was tested using The Cochrane chi(2) test and the Moran's I-2 statistic. Possible publication bias was assessed through the funnel plot and the Egger regression test. A p-value of < 0.10 will be considered as an indication for the existence of potential publication bias. All statistical analyses were carried out with Stata software version 15. Results A total of 21 studies were analyzed. It was found that longer maternity leave may decrease rates of maternal mental and physical health complaints. It was also found that longer maternity leave leads to more positive mother-child interactions, decreased infant mortality, and longer periods of breastfeeding. Conclusion Maternity leave of 12 weeks or more confers the greatest benefit for mothers and their infants. Significance What is already known about this topic? It is known that maternity leave enhances maternal and infant mental and physical well-being. A recent comprehensive review article outlined the importance of political policy to support national paid maternity leave in the United States. What does this study add? This study is a quantitative analysis to assess the optimal length of maternity leave to address these important maternal and infant outcomes.