Hormones regulate growth and development and stimulate activity of the ovaries in women or testes (gonads) in men.

Estrogen - Any of several steroid hormones produced mainly in the ovaries that develop and maintain the female characteristics of the body. During the last part of the follicular phase of the menstrual cycle, the level of estradiol (an estrogenic hormone) secreted by the ovaries increases and stimulates the uterine lining to begin to thicken.

Estrogen is available in non-synthetic forms, which occur naturally in the body and is available in a variety of synthetic forms as a treatment for infertility.

Progesterone - a sex hormone also produced in the corpus luteum of the ovaries to prepare the lining of the uterus for implantation of a fertilized (ovum) egg and later by the placenta to maintain pregnancy.

Follicle-stimulating hormone (FSH) and luteinizing hormone (LH) - are produced in the pituitary gland. Both are gonadotropins that stimulate the ovaries in women and the testes in men.

In women, these two hormones control reproductive functions, such as egg maturation and menstrual cycles by stimulating the production of estrogen and progesterone and the monthly release of an egg.

In men, luteinizing hormone stimulates the testes to produce testosterone. Follicle-stimulating hormone stimulates the testes to produce sperm.

Gonadotropins - Human chorionic gonadotropins (hCG) trigger ovulation and support the uterine lining. To improve the success rate of infertility management, we may recommend a Gonadotropin such as Gonal-f, Puregon or Pergonal. These drugs have been developed to trigger the ovaries to produce more eggs. The more healthy eggs we have, the better our chances are of fertilizing them and having a healthy embryo develop.

Gonadotropin Releasing Hormone (GnRH) - A hormone released in pulses from the hypothalamus to modulate the release of follicle-stimulating hormone and luteinizing hormone from the pituitary in order to cause egg development and eventual ovulation.