Hormones and the Roles They Play in the Female Menstrual Cycle

The female reproductive cycle is completely run by hormones. Without the hormones, conception would not occur. It’s no wonder that if any of the key hormones are out of whack then infertility is the result. Maintaining a  balance of this fine tuned system of glands and hormone excretions is paramount in the act of conception.

Estrogen

Estrogen is the hormone responsible for the low basal body temperatures in the first half of the cycle. Estrogen prompts the cervix to produce the fertile quality cervical fluid. It controls the entire menstrual cycle.

Follicle-stimulating Hormone (FSH)

FSH is produced by the pituitary gland in the first half of the reproductive cycle. FSH is the hormone responsible for prompting the ovaries to produce mature ova or eggs  and the production of estrogen.

Gonadotropin Releasing Hormone (GnRH)

GnRH is produced by the hypothalamus in the brain. It stimulates the pituitary gland in the production of FSH and lutenizing hormone (LH). This helps in the lead to follicle development and ovulation.

Human Chorionic Gonadotropin (hCG)

hCG is produced when the fertilized egg implants into the uterine wall. The production of hCG helps to maintain the corpus luteum thus keeping up the hormone production of estrogen and progesterone until the placenta takes over.

Luteinizing Hormone (LH)

LH is produced by the pituitary gland. It is released in one surge prior to ovulation, which in fact prompts ovulation to occur.

Progesterone

Progesterone is produced by the corpus luteum after ovulation has occurred. Progesterone is responsible for the higher basal body temperatures. It helps to build and maintain the uterine lining for the fertilized egg and helps to keep the lining should pregnancy occur. Progesterone is also responsible for the drying up of the cervical fluid and for the change in cervical position during the second half of the reproductive cycle.

Prolactin

Prolactin is produced when breastfeeding by the pituitary gland. Prolactin stimulates the production of milk and hinders ovulation. Sometimes the pituitary gland produces prolactin when breastfeeding isn’t occurring. This is known as an imbalance in hormones and the result is infertility.

All these hormones work together – being released at key moments throughout the cycle in order to bring about ovulation – the release of the egg from the ovary – and in helping to prepare the body for possible pregnancy. Any imbalance in one or all of these hormones causes infertility. Most of the time these imbalances can be corrected with over-the-counter remedies or with prescription medications.

The testing for hormone levels are simple – blood tests drawn from a vein in the arm at certain points during the cycle month or measured from a saliva sample.