Belsti, Y.Mousa, A.Jackson, H.Moran, L.J.Palmer, K.R.Dhungana, R.R.Callander, E.Rolnik, D.L.Teede, H.Enticott, J.2025-03-112025-03-112024Drug Safety, 2024; 48(1):87-970114-59160114-5916https://hdl.handle.net/2440/143800Background and Objective: Medication use is increasing to treat both pre-existing and pregnancy-related medical conditions or complications. This study aims to investigate factors associated with multiple medication use during pregnancy, as well as any increased risk of pregnancy complications for women taking multiple medications. Methods: A retrospective analysis of routinely collected medical records of singleton pregnant women was conducted in Southeast Melbourne, Australia, between 2016 and 2021. Self-reported medication use was recorded as part of routine medical care, starting from the frst antenatal booking appointment and continuing for every subsequent antenatal appointment until birth. Multimorbidity was defned as having two or more medical conditions. Logistic regression was used to assess factors infuencing multiple medication use (defned as taking two or more non-supplemental medications at any stage of pregnancy) and associations with pregnancy complications. Results: Of 48,502 participants, 34.9% used one medication, while 11.7% used multiple medications. Women of older age (30–34, 35–39, and ≥ 40 years), higher body mass index (25.0–29.9 kg/m2 and ≥ 30 kg/m2 ), born in Australasia and Oceania, higher socioeconomic status, and multimorbidity were more likely to use multiple medications during pregnancy. Women taking multiple medications had a higher risk of preterm and caesarean deliveries, fetal death, and neonatal admissions to intensive care. Sensitivity analyses exploring diferent morbidity categories produced no changes to fndings. Conclusions: Medication use during pregnancy is prevalent, with many pregnant mothers taking multiple medications. Given the rising maternal age, body mass index, and morbidities in pregnancy, the use of medications during pregnancy is increasing. Such use correlates with an increased chance of adverse pregnancy outcomes. In the context of limited trials on the safety and efcacy of medications in pregnancy, timely harnessing of the information available within routine medical records for post-marketing surveillance is important.en© The Author(s) 2024. Open Access This article is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License, which permits any non-commercial use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article’s Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article’s Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by-nc/4.0/.HumansPregnancy ComplicationsPolypharmacyRisk FactorsRetrospective StudiesPregnancyAdultAustraliaFemaleYoung AdultEthnicityHumansPregnancy ComplicationsPolypharmacyRisk FactorsRetrospective StudiesPregnancyAdultAustraliaFemaleYoung AdultEthnicityJournal article10.1007/s40264-024-01482-w711907Moran, L.J. [0000-0001-5772-6484]