THURSDAY, Oct. 17, 2024 (HealthDay News) -- Paternal metformin use during the period of sperm development is not associated with an increased risk for congenital malformations in offspring, according to a study published online Oct. 16 in The BMJ.
Lin-Chieh Meng, from the National Taiwan University, and colleagues examined the association between paternal metformin use and the risk for congenital malformations in offspring in a population-based cross-sectional study. Participants included 619,389 offspring in the Norwegian cohort during 2010 to 2021 and 2,563,812 in the Taiwanese cohort during 2004 to 2018.
Paternal data on metformin use during the period of sperm development were available for 2,075 offspring in Norway and 15,276 in Taiwan. Of these offspring, 5.0 and 3.4 percent in Norway and Taiwan, respectively, had congenital malformations. The researchers found that in an unadjusted analysis, the risks for any congenital malformation associated with paternal metformin use were increased; with increasing control of confounding, the risk was attenuated. The relative risks of any malformations in association with paternal metformin use were 1.29 (95 percent confidence interval [CI], 1.07 to 1.55) and 1.08 (95 percent CI, 0.99 to 1.17) in Norway and Taiwan, respectively, in an unadjusted analysis, and 1.20 (95 percent CI, 0.94 to 1.53) and 0.93 (95 percent CI, 0.80 to 1.07), respectively, in an analysis restricted to fathers with type 2 diabetes mellitus.
"These results provide reassurance and can assist clinicians in making informed treatment decisions when selecting metformin in the treatment of type 2 diabetes mellitus among men who are planning a family," the authors write.