About Estrogen and Progesterone

Estrogen and Progesterone are
female sex hormones. They are
produced in the ovaries by
developing follicles, the corpus
luteum and the placenta. Both of
them are vital for the general health of the female and the
fetus after fertilization. They are
also important in the menstrual
cycle of females. They even have
medical uses. There is a lot of
health information in the World- Wide Web which describes these
two sex hormones, but this is a
short and detailed article of
their main roles and uses. Their Role in the Menstrual Cycle There two other sex hormones
(FSH and LH) affect the
development of the follicles in
the beginning of the menstrual
cycle. Estrogen and
progesterone are then produced in the follicles. Once estrogen is
produced and secreted by the
follicles (approximately day 5 or
6 of the cycle), it stimulates the
production of more FSH
receptors on the follicle, thereby increasing the amount of
estrogen secreted. With the help
of positive feedback, the
estrogen levels rise dramatically
(day 8-12). This stimulates the
repair of the uterus lining (endometrium). On day 12, the
estrogen levels peak and then
decline, leading to ovulation due
to sharp incline of LH. The follicle
which released the egg cell is
then converted into the corpus luteum. The corpus luteum
secretes progesterone which
repairs the endometrium further.
Estrogen is also secreted by the
corpus luteum, however in a
much smaller amount that progesterone. Both estrogen
and progesterone levels peak
and then decline if no
fertilization occurs (day 22-24).
This results in menstruation. Other Roles and Uses Progesterone and estrogen are
needed throughout pregnancy.
They develop the endometrium
throughout the entire
pregnancy. At first, they are
secreted by the corpus luteum. By the middle of pregnancy, the
corpus luteum degenerates but
estrogen and progesterone are
still secreted by cells in the
placenta. The levels of estrogen
and progesterone increase constantly throughout
pregnancy until childbirth occurs.
The two sex hormones also
develop female sexual
characteristics. It is also known
that estrogen affects the growth and development of the
brain, breasts, bones, liver and
heart. It even regulates our
metabolism. Progesterone is
known to encourage the
production of milk in the breasts during pregnancy. Both of them
are present in some forms of
contraceptive pills, better known
as the pill. This has some effects
on health and the menstrual
cycle. The main effect of the pill is to prevent ovulation from
happening and thereby
preventing pregnancy. The pill
ensures that females have high
levels of both of these sex
hormones in their bodies. This inhibits the secretion of FSH and
thereby the development of the
follicle in order to release its egg
cell. Summary Estrogen and Progesterone are
sex hormones responsible for
the repair and development of
the endometrium. They have
vital roles in pregnancy, where
they develop the endometrium even more. Estrogen and
Progesterone have other roles
and uses such as; developing
organs, producing milk during
pregnancy and their use in the
contraceptive pill.