Introduction Hormonal contraceptives contain synthetic oestrogens and/or progestogens that can alter the endogenous production of oestradiol and progesterone, which potentially affect aspects of health and performance important for military employment. The nature of military service—operating away from home for prolonged periods, often in austere environments—might influence the choice of hormonal contraceptives of servicewomen. Hormonal contraceptive use and the primary reasons for use in British servicewomen are poorly understood.

Methods All trained servicewomen in the UK Armed Forces (N=14 500) with an active email were invited to respond to an online questionnaire. The questionnaire asked about demographics, current hormonal contraceptive use and reasons for choosing to use hormonal contraceptives. The survey was open for 3 months.

Results A total of 3395 servicewomen completed the questionnaire (23% response rate). Hormonal contraceptives were currently used by 58% of servicewomen. The most common methods were the contraceptive pill (20% of all respondents) and the intrauterine system (17%). The main reasons for using hormonal contraceptives were to prevent pregnancy (78%) and to control or stop the menstrual cycle (61%).

Conclusions A high proportion of UK servicewomen use hormonal contraceptives, particularly younger women, with the contraceptive pill the most popular method. The high proportion of women using hormonal contraceptives to control or stop menstrual bleeding is likely determined by the unique cultural and environmental barriers of military employment.