Merged nuMoM2b Dataset in Nulliparous Pregnancy Outcomes Study: Monitoring Mothers-to-be

79 individual datasets from the nuMoM2b study were merged into a single dataset, with one participant per row. Out of the 79 individual datasets, 9 datasets have multiple rows per participant for repeated responses. In order to combine the data into a structure with one row per participant, the repeated records in the 9 datasets were transposed into additional variables (columns). For example, if the variable A03A02a has three observations for the same participant (rows), the observations were transposed into additional variables (columns) as follows: A03A02a (original variable), A03A02a_1 (repeated response #1), and A03A02a_2 (repeated response #2).
Study Description
NuMoM2b studied underlying, interrelated, mechanisms of adverse pregnancy outcomes (e.g., preterm birth, preeclampsia, fetal growth restriction) in pregnant women with no previous pregnancy lasting 20 weeks-0 days or more estimated gestational age (nulliparas). The network included 8 clinical sites, subsites, NICHD, and a data center. Women enrolled early in pregnancy and were followed through delivery, with study visits at 6 weeks-0 days to 13 weeks-6 days, 16 weeks-0 days to 21 weeks-6 days, 22 weeks-0 days to 29 weeks-6 days gestation, and delivery. Data collected through interviews, self-administered questionnaires, clinical measurements, ultrasounds, and medical records review included demographic, psychosocial, dietary, physiologic, health, and pregnancy outcome information. Subsets of participants enrolled in sleep disordered breathing, sleep patterns and quality, and fetal adrenal gland substudies. Pregnant women with no previous pregnancy lasting =20 weeks estimated gestational age (nulliparas); although 10,038 women enrolled in the study, during consent, only 9,289 of these women agreed to release their data into shared databases maintained by NIH