Estrogen and progesterone are the two major hormones that affect women's reproductive cycles. Presence, absence or timing of menstrual cycles, premenstrual syndrome, pregnancy and menopause are all influenced by the amount of estrogen or progesterone circulating in the body. In addition, these hormones can affect other body functions or organs such as the gastrointestinal system.
Progesterone is one of several sex hormone compounds called progestins. Progesterone is probably the best-known of these hormones, and levels rise and fall throughout a woman's life. This hormone assists with breast development and function during puberty, menstrual cycles and pregnancy. Progesterone prepares the eggs for fertilization; if pregnancy does not result after ovulation, progesterone levels drop. During and after menopause, progesterone levels drop and remain at a level about one third of the levels in younger women.
Estrogens are sexual hormones that are present in women and, in smaller amounts, in men. Estrogen signals guide formation of the female reproductive system and the appearance of secondary sex characteristics at puberty and affect many other body systems. Estrogen levels rise during the menstrual cycle to stimulate the maturation of eggs, then fall rapidly to restart the cycle if pregnancy does not take place. In menopause, estrogen levels decline.
Progesterone and Constipation
The menstrual cycle is a time of fluctuating progesterone and estrogen levels, and there is evidence that constipation may result from the changing levels. In one study published in the October 2006 "Neurogastroenterology and Motility," postmenopausal women who were given progesterone showed a delay in the speed at which the colon emptied. The administration of progesterone also resulted in a looser stool.
A study reported in the September 2003 "Korean Journal of Internal Medicine" examined women who were in the luteal phase of the menstrual cycle -- the second two weeks after the egg has been released from the ovary -- when both estrogen and progesterone levels drop. The study showed the food the women ate took longer to digest and pass through the colon. The 2005 "Tohoku Journal of Experimental Medicine" reported that women who tended to be constipated were likely to become more constipated just prior to menstruation, or during the luteal phase of the menstrual cycle.
The interplay of estrogen and progesterone during the menstrual cycle, onset of menopause and post-menopause is complex. Although these hormones may be a factor in constipation, there are many other possible causes. If you have questions or concerns, consult a healthcare professional.