{"doi":"10.1002/ijgo.70553","title":"Prenatal vitamin D levels and postpartum hemorrhage in a rural Alaska cohort","abstract":"OBJECTIVE: To examine the relationship between prenatal vitamin D serum levels and postpartum bleeding. METHODS: We conducted a retrospective electronic health record cohort study of pregnant Alaska Native and American Indian (ANAI) people in southwestern Alaska who had at least one prenatal vitamin D level measurement recorded and had a vaginal birth between January 2017 and December 2019. Prenatal vitamin D level was the independent variable; postpartum abnormal bleeding and hemorrhage occurrence after a vaginal birth were the primary outcomes. RESULTS: A total of 1343 index pregnancies were included in this study, of which 1258 (94%) had a vaginal birth with 370 (29%) experiencing blood loss ≥500 mL and 127 (10%) ≥1000 mL. Risk factors included prior postpartum hemorrhage, suspected macrosomia, twin gestation, magnesium sulfate use in the setting of pre-eclampsia, induction time >36 h, oxytocin use >12 h and third stage of labor >20 min. Deficient vitamin D levels (under 12 ng/mL) were found in 10.5%, 4.8%, and 5.3% of records in the first, second and third trimesters, respectively. Logistic regression indicated an association between vitamin D level under 12 ng/mL in the first trimester and postpartum bleeding ≥500 mL (n = 540, P = 0.0097, odds ratio [OR] = 2.2). No association was found between abnormal bleeding and being vitamin D deficient in the second and third trimesters. CONCLUSION: There is a need for further research of vitamin D screening and supplementation before and during pregnancy as a possible risk reduction tool for abnormal postpartum bleeding.","journal":"International Journal of Gynecology & Obstetrics","year":2025,"id":580248,"datarank":0.0,"base_score":0.0,"endowment":0.0,"self_citation_contribution":0.0,"citation_network_contribution":0.0,"self_endowment_contribution":0.0,"citer_contribution":0.0,"corpus_percentile":null,"corpus_rank":null,"citation_count":0,"citer_count":0,"citers_with_citation_signal":0,"citers_with_endowment":0,"datacite_reuse_total":0,"is_dataset":false,"is_dataset_confidence":0.8062,"is_data_producer":false,"deposit_databanks":null,"is_oa":true,"file_count":0,"downloads":0,"has_version_chain":false,"published_date":"2025-01-01","fair_score":null,"fair_percentile":null,"algorithm_id":"datarank_citation_only_1hop_v6","ranking_scope":"data_only","authors":[{"id":385691,"name":"Julie A. Beans","orcid":"0000-0003-4363-9763","position":1,"is_corresponding":false},{"id":521229,"name":"Gretchen Day","orcid":"0000-0003-4697-1884","position":2,"is_corresponding":false},{"id":1491500,"name":"Lauryl Torkelson","orcid":null,"position":3,"is_corresponding":false},{"id":1491060,"name":"Anjali Madeira","orcid":"0009-0004-8865-622X","position":4,"is_corresponding":false},{"id":942919,"name":"David M. Compton","orcid":"0000-0001-9669-1616","position":5,"is_corresponding":false},{"id":419921,"name":"Joseph Klejka","orcid":"0000-0003-4104-7086","position":6,"is_corresponding":false},{"id":432793,"name":"Jennifer L. Shaw","orcid":"0000-0002-1824-6063","position":7,"is_corresponding":false},{"id":1491059,"name":"Reinou S. Groen","orcid":"0000-0002-1372-6068","position":0,"is_corresponding":true}],"reference_count":28,"raw_metadata":null,"created_at":"2026-07-19T02:58:38.868285Z","pmid":"41195982","pmcid":null,"fwci":null,"citation_percentile":null,"influential_citations":0,"oa_status":null,"license":null,"views":0,"total_file_size_bytes":0,"version_count":0,"fair_f":null,"fair_a":null,"fair_i":null,"fair_r":null,"fair_zscore":null,"fair_rationale":null,"fair_model":null,"fair_agent_version":null,"fair_fulltext_source":null,"fair_has_llm":null,"fair_computed_at":null,"clinical_trials":[],"software_tools":[],"db_accessions":[],"linked_datasets":[],"topics":[]}