Pregnancy 24/7 Offspring Study

Over the past three decades, there has been an alarming increase in the incidence of childhood obesity. Childhood obesity leads to early onset of cardiovascular risk factors, and both obesity and cardiovascular risk factors track into adulthood and contribute to the epidemic of cardiovascular disease (CVD). The Developmental Origins of Health and Disease theory posits that risk for obesity and CVD is, in part, programmed in utero. To prevent this early entrenchment into obesity and CVD, identification of modifiable maternal factors during pregnancy that later impact offspring risk in early childhood is essential. A surprising lack of research investigates the role of prenatal sedentary behavior (SED), moderate-to-vigorous-intensity physical activity (MVPA), and the novel 24-hour behavior paradigm (the composition of SED, physical activity, and sleep) on these adverse offspring outcomes. This is a critical research gap because there is strong physiological rationale that SED, MVPA, and 24-hour behavior in pregnancy could influence offspring health, and these behaviors are modifiable targets for intervention during pregnancy.

This project will address these research gaps with high rigor by leveraging the multi-center cohort study (Pregnancy 24/7, NCT04749849). In Pregnancy 24/7, SED, physical activity, and sleep were prospectively measured using state-of-the-art monitors (activPAL3 micro, Actiwatch Spectrum Plus), along with obesity, gestational weight gain, diet, smoking and adverse pregnancy and birth outcomes across pregnancy. In direct response to the NHLBI's NOT-HL-19-695, the scope of the Pregnancy 24/7 cohort study was expanded by conducting a separate cohort study in the participants' offspring (Pregnancy 24/7 Offspring Study). In the Offspring Study, maternal exposures (already collected in Pregnancy 24/7) will be combined with new, comprehensive assessments of the child's postnatal exposures and outcomes through 24 months. This approach will allow the investigative team to isolate the effects of pregnancy SED, MVPA, and 24-hr behavior on offspring growth and CVD risk measures in early childhood. Growth mixture modeling and state-of-the-art compositional data analyses will be used to address the following aims:

AIM 1: Examine associations of SED in pregnancy with offspring growth and CVD risk measures H1: Offspring of women with higher SED across pregnancy will have more rapid increases in BMIz (primary) and higher adiposity, blood pressure, and pulse wave velocity (secondary) through 24 months.

AIM 2: Examine associations of MVPA in pregnancy with offspring growth and CVD risk measures H2: Offspring of women with lower MVPA across pregnancy will have more rapid increases in BMIz (primary) and higher adiposity, blood pressure, and pulse wave velocity (secondary) through 24 months.

AIM 3: Determine optimal 24-hr behavior compositions in pregnancy to reduce the risk of adverse growth and CVD risk measures in the offspring H3: Statistically reallocating time in SED for LPA or MVPA, but not sleep (in adequate duration sleepers) across pregnancy will be associated with less rapid increases in BMIz (primary), and lower adiposity, blood pressure, and pulse wave velocity (secondary) in the offspring through 24 months.

By combining prenatal and postnatal exposure data, this approach uniquely allows the investigative team to isolate the effects of pregnancy SED, MVPA, and 24-hr behavior on offspring obesity and CVD risk measures in early childhood. This project will inform critically needed primordial prevention interventions to decrease the risk of obesity and CVD.

Maternal Inclusion Criteria:

• Enrolled in Pregnancy 24/7 Study.
• Completed at least one 24-hr behavior assessment, with valid objective activity monitor data and questionnaires.
• Pregnancy resulted in singleton live birth.

Offspring Exclusion Criteria:

-Child diagnosed with congenital or chromosomal abnormalities that may affect growth or CVD risk.