Placental Vascular Resistance and Offspring Growth From Birth to Age 2 Years.

Importance: Umbilical artery Doppler indices provide indirect measures of placental function, with elevated vascular resistance associated with adverse perinatal outcomes, but their association with postnatal growth remains understudied. Objective: To examine the association between placental vascular resistance and early-childhood physical growth. Design, Setting, and Participants: This cohort study used hospital electronic medical records and Maternal and Child Health Information System data of all singleton live births from May 18, 2012, to October 30, 2023, at Wuhan Children's Hospital (Wuhan Maternal and Child Health Hospital). Exposure: Placental vascular resistance was assessed through routine prenatal Doppler ultrasonography measurements of pulsatility index, resistance index, and systolic-to-diastolic ratio across 4 gestational windows (21-24 weeks, 25-28 weeks, 29-32 weeks, and 33-36 weeks). Main Outcomes and Measures: Child growth parameters from birth to age 2 years, including stunting, underweight, wasting, were defined as length for age, weight for age, and weight for length below the third percentile, respectively. Group-based multitrajectory modeling was conducted to characterize multiple trajectories of weight-for-age and length-for-age z scores. Results: A total of 52 660 mother-infant pairs were included (mean [SD] maternal age, 30.2 [3.9] years; 53.0% male offspring; mean [SD] gestational age, 38.8 [1.4] weeks). The prevalence rates of underweight, stunting, and wasting among children were 0.2% (n = 76), 0.3% (n = 101), and 0.8% (n = 284), respectively. Elevated placental vascular resistance at 21 to 24 weeks was associated with increased risks of childhood underweight (resistance index: odds ratio [OR], 1.27 [95% CI, 1.11-1.47]) and stunting (pulsatility index: OR, 1.29 [95% CI, 1.10-1.51]; resistance index: OR, 1.19 [95% CI, 1.05-1.35]; systolic-to-diastolic ratio: OR, 1.52 [95% CI, 1.11-2.07]). In the multitrajectory analysis, increased placental vascular resistance across all 4 gestational windows was significantly associated with a higher odds of children belonging to the persistently low, early-low and catch-up, and below-average groups and a lower odds of belonging to the persistently high group compared with the average group. Conclusions and Relevance: In this large cohort study of mother-child pairs followed up from pregnancy to childhood, elevated placental vascular resistance was associated with an increased risk of childhood underweight and stunting, highlighting the clinical importance of routinely monitoring Doppler indices during prenatal checkups.