Contraceptive use and childbirth rates by service branch during the first 24 months on active duty in the United States military from 2013 to 2018: a retrospective cohort analysis

To measure the association of military branch-specific contraceptive education and access policy during basic training with contraceptive use and childbirth among new recruits. Secondary analysis of insurance records from 92,072 active duty servicewomen who started basic training between 2013 and 2017. Exposure to reproductive health education and access to contraception during basic training differ by military branch. Highly effective contraception use (pills, patch, ring, shot, implants or intrauterine contraception) at 6 months on active duty [Army (18.1%), Air Force (27.4%), Marines (26.5%) and Navy (37.6%), p