No body fat to store estrogen. Therefore, no LH upsurge. So what happens. No LH upsurge, to follicle released. Tagamet Suppress dopamine.
Dopamine is antagonist to prolactin.
If you suppress dopamine, then prolactin goes up, and this causes amenorrhea. Menopause Failure of ovarian function FSH is over 40. Should not be able to palpate uterus as well.