Leiomyomas: steroid receptor content. Variation within normal menstrual cycles.

In an attempt to clarify further the relationship between ovarian function and uterine leiomyomas, we investigated the cytoplasmic estrogen and progesterone receptor content in these uterine tumors. The study population consisted of 17 women of reproductive age at various stages of ovulatory menstrual cycles. Serum samples were analyzed for estrogen and progesterone content; tissue samples from endometrium, myometrium, and leiomyomas were analyzed for cytoplasmic estrogen and progesterone receptor content. The levels of cytoplasmic estrogen and progesterone receptor in leiomyomas demonstrated the same quantitative and qualitative cyclic changes throughout the menstrual cycle apparently in response to variations in circulating estrogen and progesterone as found in endometrium and myometrium.