Plasma progesterone concentration in thyrotoxic women with menstrual disturbance

Abstract

Plasma progesterone concentration was estimated for 28 consecutive days by competitive protein-binding method in 15 thyrotoxic women (ten with hypomenorrhea and five with amenorrhea) before commencement of therapy (except in one patient) in order to determine whether ovulation was occurring in these women. A similar estimation was also performed in 12 euthyroid normally menstruating women who served as control subjects. The results showed that the progesterone levels in thyrotoxic women who were still menstruating (though scantily) rose to a plateau in the second half of the menstrual cycle and fell just before the onset of menstruation, suggesting that these patients had ovulated. There was no significant difference in the progesterone levels of these hypomenorrheic women and those of euthyroid normally menstruating women. However, in thyrotoxic women who had developend amenorrhea, progesterone levels were low (virtually undetectable in most cases) throughout the period of the study, suggesting a failure of ovulation in this group of subjects.