ABSTRACT
Adverse pregnancy outcomes, including gestational hypertension and preeclampsia, affect 10-20% of pregnant
women and are major risk factors for future maternal cardiovascular disease (CVD). Though moderate-to-
vigorous intensity physical activity (MVPA) during pregnancy can reduce these risks, less than 25% of pregnant
women meet MVPA guidelines. Identification of additional modifiable behaviors that could reduce maternal
health risks during pregnancy is needed to inform clinical interventions and practice. Remarkably, little is known
about the role of sedentary behavior or sleep in adverse pregnancy outcomes that increase future CVD risk. This
is a critical research gap because sedentary behavior and sleep are increasingly recognized as CVD risk factors
in the general population, independent of MVPA. Unfortunately, existing studies in pregnancy largely focus on
MVPA rather than the emerging paradigm that considers the full 24-hour behavioral cycle (i.e., sedentary
behavior, sleep, light-intensity physical activity, and MVPA), lack repeated measures, use suboptimal
assessment methods, and fail to measure clinically relevant outcomes. Clarifying how sedentary behavior and
sleep influence pregnancy outcomes could inform intervention targets and guidelines to improve cardiovascular
health during and after pregnancy. The overall goal of the proposed study is to examine the associations of
sedentary behavior (Aim 1) and sleep (Aim 2) with hypertensive disorders of pregnancy and other adverse
pregnancy outcomes that increase future CVD risk. Novel statistical methods will be used to determine optimal
24-hour behavioral patterns (Aim 3) during pregnancy for cardiovascular health. For this, 500 women in early
pregnancy will be recruited to take part in a multi-site (Universities of Iowa and Pittsburgh) cohort study. Women
will wear three state-of-the-art devices for seven days in each trimester of pregnancy to assess sedentary
behavior (activPAL micro 3), sleep (ActiWatch Spectrum Plus), and physical activity (ActiGraph GT3X).
Hypertensive disorders of pregnancy and other adverse outcomes will be obtained through medical chart
abstraction. We hypothesize that women with a high sedentary behavior pattern, short sleep duration pattern,
and poor sleep quality pattern across trimesters will be more likely to have hypertensive disorders of pregnancy
(primary), gestational diabetes, preterm birth, small-for-gestational age infants, high blood pressure, and poor
glycemic control (secondary). Further, we hypothesize that statistically reallocating time spent in sedentary
behavior for physical activity (LPA or MVPA), but not sleep (among adequate or high duration sleepers), will be
associated with lower incidence of these adverse outcomes. In direct response to the NHLBI Research Priority
3.CC.04, this project will use advanced methods and models to assess and characterize the 24-hour behavioral
cycle during pregnancy to better understand differences in health. This project will inform guidelines on optimal
24-hour behavioral patterns in pregnancy, as well as lay the foundation for future studies testing behavioral
interventions in pregnancy to achieve optimal outcomes and improve women’s long-term cardiovascular health.
