Association of a Lifestyle Intervention with Blood Pressure Trajectories During Pregnancy and Postpartum in Women with Pre-pregnancy Overweight and Obesity.

Objectives: Healthy lifestyle, including healthy diet and physical activity, has been associated with lower blood pressure (BP). We hypothesized that overweight/obese women randomized to a lifestyle intervention beginning in early pregnancy would be less likely to have a higher BP trajectory.

Methods: The Health in Pregnancy and Postpartum study promoted a healthy lifestyle in pregnant and postpartum women with pre-pregnancy overweight or obesity. BP was measured at study visits at ≤ 16 and 32 weeks of pregnancy and 6 and 12 months postpartum. Latent class trajectories were constructed to identify groups of participants with similar BP patterns throughout the study period. Odds of being assigned to the higher BP trajectories between the intervention and control group were determined with logistic regression, adjusted for age, race, pre-pregnancy BMI, gestational weight gain, smoking during the study period, and household income.

Results: Of the 219 participants enrolled (44.3% Black participants, 55.7% White participants, mean age = 29.7 ± 0.3 years), 112 (51.1%) were randomized to the intervention. Two systolic and diastolic BP trajectory groups were identified (Low-Stable, Moderate-Increasing). Randomization to the lifestyle intervention was not associated with odds of Moderate-Increasing systolic (OR 0.83, 95%CI 0.4, 1.6) or diastolic (OR 0.67, 95%CI 0.3, 1.3) BP trajectory assignment. Those in the Moderate-Increasing BP groups had higher BMI and were more likely to have an adverse pregnancy outcome.

Conclusions: A lifestyle intervention initiated in early pregnancy to help prevent excessive gestational weight gain was not associated with odds of specific BP patterns through pregnancy and postpartum.