ROBERTS TA, et al. - Considering the association of variation among service-branches in contraceptive education and access during initial training with differences in contraceptive use and childbirth rates among United States servicewomen despite access to a uniform health benefit including no-cost reproductive healthcare and contraception, researchers sought to ascertain if changes in branch-specific contraceptive policies can influence reproductive outcomes among junior enlisted women in that service branch. They performed a secondary analysis of insurance records from 70,852 servicewomen who commenced basic training between October 2013 and December 2016 in order to determine the longitudinal influence of a Navy policy change extending contraceptive access during basic training implemented in January 2015 and a Marine Corps policy change limiting contraceptive access during basic training implemented in January 2016 on: contraception use (pills, patches, rings, injectable, implantable, and intrauterine) at 6-months, long-acting reversible contraception use at 6-months, and childbirth prior to 24-months after service entry. Compared with the longitudinal variation observed among women attending Army or Air Force basic training, adapting policies to expand contraceptive access during Navy basic training in January 2015 improved contraception use from 33.1% of sailors to 39.2% of sailors before and after the policy change, and long-acting reversible contraception use from 11.0% to 22.7%. Outcomes suggest that contraception use among junior enlisted is influenced by basic training contraceptive policy. Contraception use could be increased and childbirth rates could be reduced with implementing best practices across the military among junior enlisted.