Housing instability and adverse perinatal outcomes: a systematic review

OBJECTIVE: Our objective was to conduct a systematic review of the published literature on housing instability during pregnancy and adverse pregnancy outcomes and perinatal healthcare utilization. DATA SOURCES: We performed a systematic search in November 2020 using Embase, MEDLINE, Cochrane Library, and Scopus using terms related to housing instability during pregnancy, adverse pregnancy outcomes, and perinatal healthcare utilization. The search was limited to the United States. STUDY ELIGIBILITY CRITERIA: Studies examining housing instability (including homelessness) during pregnancy and adverse pregnancy outcomes (including preterm birth, low birthweight neonates, and maternal morbidity) and perinatal healthcare utilization were included. METHODS: Two authors screened abstracts and full-length articles for inclusion. The final cohort consisted of 14 studies. Two authors independently extracted data from each article and assessed the study quality using the Grading of Recommendations, Assessment, Development, and Evaluation tool. Risk of bias was assessed using the National Institutes of Health Study Quality Assessment Tools. RESULTS: All included studies were observational, including retrospective cohort (n=10, 71.4%), cross-sectional observational (n=3, 21.4%), or prospective cohort studies (n=1, 7.1%). There was significant heterogeneity in the definitions of housing instability and homelessness. Most of the studies only examined homelessness (n=9, 64.3%) and not lesser degrees of housing instability. Housing instability and homelessness during pregnancy were significantly associated with preterm birth, low birthweight neonates, neonatal intensive care unit admission, and delivery complications. Among studies examining perinatal healthcare utilization, housing instability was associated with inadequate prenatal care and increased hospital utilization. All studies exhibited moderate, low, or very low study quality and fair or poor internal validity. CONCLUSION: Although data on housing instability during pregnancy are limited by the lack of a standardized definition, a consistent relationship between housing instability and adverse pregnancy outcomes has been suggested by this systematic review. The evaluation and development of a standardized definition and measurement of housing instability among pregnant individuals is warranted to address future interventions targeted to housing instability during pregnancy.