Patient, Partner, and Provider Determinants of Postpartum Contraception and Inter-Pregnancy Intervals - ABSTRACT Nearly 1 in 5 postpartum patients will have a repeat pregnancy after a short interpregnancy interval (sIPI), defined as less than 18 months between a prior birth and subsequent conception. Several adverse outcomes are linked to sIPI, including preterm delivery, low birth weight, and infant mortality. Risks are greatest for shorter IPIs and unintended pregnancies. Guidelines therefore recommend clinicians advise postpartum patients to avoid a sIPI of <6 months and consider delaying pregnancy for 18 months; contraceptive options should also be discussed. Yet up to 40% of patients never receive any postpartum care, missing opportunities for counseling. Health system factors, like fragmentation in care and difficulty scheduling and navigating visits, are frequently cited barriers. Among patients who do attend postpartum care, only half receive counseling on healthy birth spacing. While contraceptive counseling is usually provided, it is rarely comprehensive or patient-centered. As a result, most patients are unaware of the consequences of sIPI and the time recommended between pregnancies. Nearly half do not use any postpartum contraception or use a less effective method, increasing risk of repeat pregnancy. On the patient-level, the role of psychosocial (e.g., depression, stress) and behavioral (e.g., alcohol use, sleep) factors on postpartum contraceptive use and sIPI are poorly understood, despite the considerable physical and mental demands of the postpartum period. Similarly, the impact of low health literacy, or difficulty `finding, understanding, and using information to inform health actions' has been linked to worse contraceptive knowledge and poor understanding of fecundity, but has not been studied in relation to postpartum contraceptive use or sIPI. Finally, despite reproduction being a dyadic behavior, partner-level factors, including partner health literacy and partner-reported psychosocial and behavioral factors, and their impact on postpartum contraceptive use and sIPI remain understudied. Research has also not considered how these factors vary and interact within a dyad. Unraveling these relationships can provide crucial information on how - and who - to target in future interventions. To address these evidence gaps, we will conduct a longitudinal cohort study among 960 English- and Spanish-speaking postpartum patients recruited from academic and community health centers in Chicago, IL and any eligible, cohabitating partners (N=400). Data will be collected at 6 timepoints over 21 months to capture modifiable, multilevel factors affecting postpartum contraceptive use and unintended sIPI. Our aims are to: 1) Examine the effect of patient health literacy and psychosocial and behavioral factors on birth spacing knowledge, postpartum contraceptive method choice, use, and unintended sIPI; 2) Investigate the impact of the health system on patient postpartum care utilization, birth spacing knowledge, postpartum contraceptive method choice, and unintended sIPI; and 3) Among dyads, explore the influence of patient and partner health literacy and psychosocial and behavioral factors on postpartum contraceptive method choice, use, and unintended sIPI.
