Crouching in a trench on the front lines in eastern Ukraine, Olena felt the ovulation app on her phone buzz.

¡°I realized that I really needed to be at home making a baby, not sitting in this trench,¡± recalled Olena, a combat medic. But that wasn¡¯t an immediate option, and her desire to start a family was as strong as her need to serve.

After about six months of trying ¡ª navigating appointments with fertility doctors around her limited leave ¡ª ¡°it finally happened,¡± said Olena, who like other women interviewed for this article requested that only her first name be used for reasons of military protocol. She got pregnant, but continued to serve.