Birth and Early Childhood Outcomes in Families Receiving an Unconditional Prenatal Cash Benefit.

Importance: The Canadian province of Manitoba has offered an unconditional cash benefit (maximum CAD $81.41/mo) to low-income pregnant women since 2001. Evaluations have found the benefit was associated with improved birth and child development outcomes, but its effectiveness may be diminishing because the benefit amount has not changed in 20 years. Objective: To examine whether the Healthy Baby Prenatal Benefit remains an effective strategy for supporting maternal and child health. Design, Setting, and Participants: This retrospective cohort study was conducted among mothers with a singleton birth in Manitoba, Canada, from 2003 to 2019. Low-income mother-child dyads were identified using income assistance records. Data analyses were conducted from June to December 2024. Exposure: Receipt of the benefit during the second and third trimesters of pregnancy. Main Outcomes and Measures: Propensity scores and inverse probability of treatment weights were developed from sociodemographic information, which were used to reduce standardized differences between benefit recipients and nonrecipients. Risk ratios (RRs) for birth outcomes and developmental vulnerability in 5 domains at kindergarten were calculated. Results: The 17 970 benefit recipients (mean [SD] age at first birth, 19.52 [3.53] years) and 8301 nonrecipients (mean [SD] age at first birth, 19.38 [3.43] years). After applying inverse probability of treatment weights, all standardized differences were less than 0.10. From 2003 to 2019, the RRs increased among recipients vs nonrecipients for low birth weight (2003: RR, 0.68 [95% CI, 0.56-0.82]; 2019: RR, 0.92 [95% CI, 0.76-1.11]), preterm birth (2003: RR, 0.72 [95% CI, 0.62-0.83]; 2019: RR, 0.95 [95% CI, 0.83-1.09]), and small-for-gestational age (2003: RR, 0.83 [95% CI, 0.71-0.96]; 2019: RR, 0.97 [95% CI, 0.83-1.43]) and decreased for large-for-gestational age (2003: RR, 1.13 [95% CI, 1.01-1.26]; 2019: RR, 1.11 [95% CI, 0.99-1.24]) and breastfeeding initiation (2003: RR, 1.06 [95% CI, 1.02-1.10]; 2019: RR, 1.01 [95% CI, 0.98-1.05]). The RR for developmental vulnerability in kindergarten increased in the domains of language and cognitive development (2003: RR, 0.77 [95% CI, 0.66-0.89]; 2019: RR, 1.07 [95% CI, 0.94-1.21]) and communication and general knowledge (2003: RR, 0.83 [95% CI, 0.72-0.96]; 2019: RR, 0.93 [95% CI, 0.82-1.05]). Conclusions and Relevance: In this cohort study of low-income mothers and newborns, the associations of the Healthy Baby Prenatal Benefit with birth and child development outcomes diminished from 2003 to 2019, with many disappearing. Given the importance of prenatal health to these outcomes, these findings suggest that the benefit amount should be increased and adjusted for inflation in future years.