It has been reported that pregnancy and childbirth lead to improved athletic performance in women, often referred to as “pregnancy doping”. This ergogenic phenomenon is said to occur for up to one year following childbirth. The mainstream media regularly reports on this theory, citing performances of elite marathoners such as Paula Radcliffe, Kara Goucher, and Ingrid Kristiansen as evidence. PURPOSE: To assess evidence that childbirth has a performance enhancing effect on female marathoners. METHODS: LexisNexis Academic and Google News databases were searched for news articles discussing pregnancy doping theory. Search terms included ((‘pregnancy doping’ OR ‘childbirth’ OR ‘pregnancy’) AND (‘performance enhancing’ AND ‘athletes’ OR ‘runners’ OR ‘marathoners’)). Leads to other news stories on the topic were also explored. Elite marathoners who competed in marathons before and after childbirth were identified from retrieved articles. Information on each identified athlete was collected from IAAF profile and other reputable resources, including athlete’s birthdate, pre-childbirth marathon personal record (PR) and post-childbirth PR, dates of each PR, and date of childbirth. Pre- and post-childbirth marathon PR’s were compared relative to time of childbirth. RESULTS: Eight elite marathoners were identified. Five of the seven elite marathoners (Goucher, Keitany, Kristiansen, O’Sullivan, and Tulu) had faster marathon PR’s after childbirth. However, only Goucher ran faster within a year after childbirth. Keitany achieved a PR 15 months after childbirth, and the three others achieved lifetime PR’s >3.5 years post-childbirth. Radcliffe, Kastor, and DeReuck never improved upon their pre-pregnancy PR’s after childbirth. CONCLUSIONS: Though physiologic adaptations to exercise during pregnancy have been studied, there are no scientific studies regarding the effect of childbirth on competitive racing performance. Only one of eight marathoners commonly cited as evidence for the ergogenic effects of pregnancy actually improved her marathon PR within a year of childbirth. While anecdotal evidence is commonly used to support expert opinion that pregnancy has a year long ergogenic effect on marathon performance, actual performance outcome data are currently insufficient to support this theory.