a Childbirth
Corpus Luteum -- What is Its Role in Fertility?
Courtesy of Ed Uthman
The bright yellow corpus luteum is fully developed.
This is how it looks in the mid-luteal phase of
the menstrual cycle following ovulation.
The corpus luteum produces progesterone, which supports the implantation of the fertilized egg.
What is progesterone and what is its role in fertility and pregnancy? Progesterone is a steroid hormone. It is initially produced by the corpus luteum. Corpus luteum is an area in the ovary which develops after ovulation. Before ovulation, progesterone levels are low. They increase right after ovulation and reach as much as 10ng/ml by the 5 or 6 day after ovulation.
Corpus luteum is part of the menstrual cycle:
1 - Menstruation 2 - Maturing follicle 3 - Mature follicle 4 - Ovulation 5 - Corpus luteum 6 - Deterioration of corpus luteum
The time right after ovulation until the next menstrual period is called the corpus luteum phase or the luteal phase. during this phase, the fertilized egg is swapped through the fallopian tube into the uterus where it implants in the next one or two weeks. The normal corpus luteum phase lasts about 14 days plus/minus 3 days.
progesterone, produced by the corpus luteum, prepares the lining of the uterus, called endometrium, for implantation and pregnancy. It prevents contractions of the uterus, so as the fertilized egg to be retained. It also prevents the development of a new follicle after implantation of the fertilized zygote. Progesterone is later produced by the placenta and maintains the pregnancy until birth.
If you do not get pregnant or if implantation does not take place, the corpus luteum will start to degenerate. The levels of progesterone will drop. This fall in hormone levels signals the uterus lining -- the endometrium -- to be melt down and to be flushed out of the uterus through the vagina. Your reproductive cycle starts again.
