Early Pregnancy Health Behavior Profiles Are Associated With Adverse Pregnancy Outcomes

PURPOSE Adverse pregnancy outcomes (APO; e.g. preterm birth, preeclampsia) impact 1 in 3 pregnancies and are a major source of maternal and neonatal morbidity. Prevention strategies are limited, but evidence shows healthy behaviors reduce the risk of APO. Behaviors associated with pregnancy health include physical activity, diet, smoking, and sleep. Whether pregnant people engage in distinct combinations of these behaviors, and how combinations of health behaviors relate to risk of APO, are unknown. We aimed to examine the association between latent classes of behavior combinations and APO. METHODS Participants (N = 8700, 26.9 ± 5.6 years, 40% underrepresented race and/or ethnicity) in the nuMoM2b Study were included. Physical activity, diet, smoking, and sleep duration were self-reported in the first trimester and scored 0-100 (higher is healthier) using the Life’s Essential 8 metric. APO were adjudicated by experts and defined as any occurrence of preterm birth (<37 weeks gestation), hypertensive disorders of pregnancy (gestational hypertension, preeclampsia, or eclampsia), gestational diabetes, small-for-gestational age (birthweight ≤10th percentile), or stillbirth. Latent classes of health behaviors were constructed with structural equation modelling and Poisson regression computed relative risk (RR) of APO among classes. RESULTS Four classes of health behaviors were found, 32% were diagnosed with ≥1 APO, and RR was significantly different among classes (Table). Associations were robust to adjustment for demographics and when excluding those with chronic hypertension or diabetes. CONCLUSION: Risk of APO was highest among those with low adherence to all four health behaviors in the first trimester, and those in classes characterized by smoking or poor diet were also at increased risk. These results may inform future research into whether combined behavioral interventions influence pregnancy outcomes and long-term maternal health factors. Table 1. - Rate ratios, frequency of APO, and health behavior scores in each latent class. Healthy Behaviors (n=3158, 36%) Active Smokers with Poor Diet (n=1807, 21%) Inactive with Poor Diet (n=2804, 32%) Least Healthy Behaviors (n=931, 11%) Adjusted APO Rate Ratio (95% CI) 1.00 (Reference) 1.26 (1.14, 1.39) 1.21 (1.10, 1.33) 1.34 (1.19, 1.52) Composite APO (n, %) 882 (30%) 635 (35%) 948 (34%) 349 (37%) Preterm Birth 237 (8%) 192 (11%) 292 (10%) 108 (12%) Early Preterm Birth 65 (2%) 57 (3%) 109 (4%) 38 (4%) Hypertensive Disorders of Pregnancy 389 (12%) 290 (16%) 406 (14%) 159 (17%) Gestational Diabetes 117 (4%) 84 (5%) 148 (5%) 47 (5%) Small for Gestational Age 327 (10%) 216 (12%) 353 (13%) 122 (13%) Stillbirth 12 (0.4%) 16 (0.9%) 20 (0.7%) 6 (0.6%) Physical activity score (mean ± SD) 92.6 ± 13.2 90.2 ± 14.2 5.5 ± 13.1 47.2 ± 42.6 Diet score (mean ± SD) 68.7 ± 20.0 16.8 ± 15.5 29.7 ± 28.2 29.0 ± 29.5 Sleep score(mean ± SD) 96.6 ± 8.1 93.2 ± 11.2 94.0 ± 10.5 37.6 ± 8.1 Smoking score (mean ± SD) 75.3 ± 26.9 47.1 ± 36.6 64.4 ± 34.7 57.7 ± 37.0 Rate ratios are adjusted for maternal age, racial and ethnic background, insurance, and education. Behaviors were scored from 0-100 based on the Life’s Essential 8 algorithm, in which scores ≥ 80 indicate “ideal” health, 50-79 indicate “moderate” health, and < 50 indicate “poor” health. APO: adverse pregnancy outcome; CI: confidence interval; SD: standard deviation. Early preterm birth defined as prior to 34 weeks gestation at birth. Supported by: U10 HD063036; U10 HD063072; U10 HD063047; U10 HD063037; U10 HD063041; U10 HD063020; U10 HD063046; U10 HD063048; U10 HD063053; T32HL083825