Some women begin to have menopausal, vasomotor symptoms while they are still menstruating regularly. If these symptoms cannot be controlled with environmental changes, then avoidance of caffeine, intake of vitamin E 400 IU daily, and very-low-dose estrogen may be prescribed (0.3mg conjugated estrogen daily or an estrogen patch 0.0375mg). Alternatively, perimenopausal women may experience periods of estradiol excess as the failing ovary temporarily responds to the elevated levels of stimulating gonadotropins with surges in estrogen production. Periodic monitoring of the endometrium is mandatory in any woman who is receiving "unopposed" estrogen.
Nonsmoking, healthy perimenopausal women (up to the age of 50) can be maintained on oral contraceptives, which will suppress vasomotor symptoms. Oral contraceptives are an appropriate option for symptomatic perimenopausal women with oligomenorrhea because they regulate the cycle, prevent pregnancy, and control vasomotor symptoms. However, because even the newer low-dose oral contraceptives have 4 times the amount of hormone needed for postmenopausal replacement purposes, changing to PERT is recommended when the woman is menopausal.
Cite this: Update on Hormone Replacement: Sorting Out the Options for Preventing Coronary Artery Disease and Osteoporosis - Medscape - Jun 29, 1996.