premenarchal

adjective
pre·​men·​ar·​chal | \ -men-ˈär-kəl How to pronounce premenarchal (audio) \
variants: or premenarcheal \ -​kē-​əl How to pronounce premenarcheal (audio) \

Medical Definition of premenarchal

: of, relating to, or being in the period of life of a female before the first menstrual period occurs