Prenatal depression exposure and infant developmental outcomes: a retrospective cohort study of reduced fetal growth indicators, elevated neonatal heart rate, and developmental trajectories in China.

Introduction: While prenatal depression is recognized as a significant public health issue, its specific impacts on fetal development and subsequent infant growth in the first year of life remain insufficiently characterized in Chinese populations. This study aimed to investigate the effects of prenatal depression exposure on neonatal outcomes and early infancy developmental trajectories. Materials and methods: This retrospective cohort study utilized data from the Jiangsu Provincial Maternal and Child Health Platform (2006-2023). A total of 146 exposed and 146 control infants were included after 1:1 propensity score matching. After matching and applying exclusion criteria neonatal anthropometric measures (gestational age, birth weight, length, head circumference), pulse rates, and longitudinal growth parameters up to 12 months were analyzed using comparative statistics and regression models. All models were adjusted for key confounders. Missing data were handled by multiple imputation. Results: Mothers with prenatal depression were younger (mean age 34.01 vs. 36.83 years) and more frequently primiparous. Exposed neonates showed significantly lower but clinically non-pathological anthropometrics: reduced gestational age (38.67 vs. 39.16 weeks, P = 0.001) but still term (≥37 weeks), lower birth weight (3,164.59 vs. 3,356.39 g, P<0.001), shorter body length (49.51 vs. 49.98 cm, P = 0.001), and nominally smaller head circumference (33.61 vs. 33.99 cm, P = 0.028). Substantial missing data limit firm conclusions regarding head circumference. Adverse birth outcomes were more prevalent, with a fourfold higher incidence of low birth weight (12% vs. 3%). Notably, exposed neonates exhibited elevated pulse rates (137.63 vs. 130.6 bpm, P = 0.008), indicative of altered autonomic regulation. Developmental differences persisted into infancy: at six months, exposed infants had lower weight (8.30 vs. 8.48 kg, P = 0.158), shorter length (75.80 vs. 76.13 cm, P = 0.049), and delayed dentition (0.55 vs. 3.86 teeth, P = 0.026), though growth velocity patterns suggested partial catch-up in linear dimensions. Conclusions: Prenatal depression exposure is associated with lower but clinically non-pathological fetal growth indicators, adverse neonatal outcomes, elevated infant heart rate, and altered early developmental trajectories. Neonatal heart rate may serve as a potential biomarker of prenatal stress. These findings support integrating mental health screening into routine prenatal care and monitoring the early growth and development of exposed infants.