• Margulis AV, Palmsten K, Andrade SE, Charlton RA, Hardy JR, Cooper WO, Hernández-Díaz S. Beginning and duration of pregnancy in automated health care databases: review of estimation methods and validation results. Pharmacoepidemiology and drug safety. 2015 Jan 28. PMID: 25627986 [PubMed].

Abstract 

To describe methods reported in the literature to estimate the beginning or duration of pregnancy in automated health care data, and to present results of validation exercises where available.