Fertility medication

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Fertility medication, better known as fertility drugs, are drugs which enhance reproductive fertility. For women, fertility medication is used to stimulate follicle development of the ovary. There are currently very few fertility medication options available for men.

Agents that enhance ovarian activity can be classified as either Gonadotropin releasing hormone, Estrogen antagonists or Gonadotropins.

Female[edit]

Gonadotropin-releasing hormone[edit]

Either Gonadotropin-releasing hormone (GnRH) or any Gonadotropin-releasing hormone agonist (i.e. Lupron) may be used. GnRH stimulates the release of gonadotropins (LH and FSH) from the anterior pituitary in the body.

Oestrogen antagonists[edit]

Fertility medication inhibiting the effects of estrogen includes Clomiphene and Aromatase inhibitors.

Clomiphene[edit]

Clomiphene (trademarked as Clomid) is a selective estrogen receptor modulator (SERM). It is the most widely used fertility drug. It is used as an ovarian stimulator by inhibiting the negative feedback of estrogen at the hypothalamus. As the negative feedback of estrogen is inhibited, the hypothalamus secretes GnRh which in turn stimulates the anterior pituitary to secrete LH and FSH which help in ovulation.

Aromatase inhibitors[edit]

Although primarily a breast cancer treatment, aromatase inhibitors can also work as fertility medication, probably through a mechanism similar to clomiphene. Aromatase inhibitors will decrease the amount of testosterone converted to estradiol. Less estradiol circulating in the body will decrease the negative feedback at the level of the hypothalamus and result in sustained FSH secretion. More FSH will be available to stimulate the ovary and mature multiple follicles for ovulation. This is a common fertility treatment to treat women with PCOS. [1]

Gonadotropins[edit]

Gonadotropins are the hormones in the body that normally stimulate the gonads (testes and ovaries). For medication, they can be extracted from urine or by genetic modification.

For example, the so-called menotropins consist of LH and FSH extracted from human urine from menopausal women.[2] FSH and FSH analogues are mainly used for ovarian hyperstimulation as well as reversal of anovulation.

There are also recombinant variants which are created by inserting the DNA coding for it into bacteriae. The bacterial DNA is then called Recombinant DNA. Examples of recombinant FSH are Follistim and Gonal F, while Luveris is a recombinant LH.

Human chorionic gonadotropin[edit]

Human chorionic gonadotropin (hCG) is normally produced during pregnancy. However, it can also replace LH as an ovulation inducer.

Other[edit]

hMG is a medication containing a follicle-stimulating hormone (FSH) and a lutenizing hormone (LH).

Male[edit]

There currently are no effective medications to treat oligospermia, so other assisted reproductive technologies are used.

Research in male fertility medication is currently ongoing. A study in Egypt assessed the efficacy of a combination of clomiphene and vitamin E in improving sperm count and sperm motility in male infertility.[3]

Adverse effects[edit]

The use of fertility drugs is highly correlated with other ovarian cancer risk factors which complicates the direct contribution of the fertility drugs to ovarian cancer. Numerous studies indicate the risk of developing ovarian cancer as a result of fertility drugs is insignificant, but long-term exposure to fertility drugs may require further studies to determine their role in ovarian tumors and other health risks. [4] Estrogen antagonists and gonadotropins may stimulate multiple follicles and other ovarian hormones leading to multiple birth and possible ovarian hyperstimulation syndrome.

Development of ovarian hyperstimulation syndrome (OHSS) is dependent on the administration of human chorionic gonadotropin (hCG) and is mediated through vascular endothelial growth factor (VEGF). OHSS is characterized as cystic enlargement of the ovaries. [5] Multiple birth is especially deleterious due to compounding risks including premature delivery and low birthweight, pre-eclampisa, and increased risk of neonatal mortality. [6] While triplet births have been declining in ART, multiple births remain over 50% of births from IVF. However, there are limitations to this date, as 4% to 8% IVF clinics to do not report their data to the CDC. [7]

See also[edit]

Manufacturers:

References[edit]

  1. ^ Badawy, A., Aal, I. A., & Abulatta, M. (2009). Clomiphene citrate or letrozole for ovulation induction in women with polycystic ovarian syndrome: a prospective randomized trial. Fertility and sterility, 92(3), 849-852
  2. ^ Menotropins at the US National Library of Medicine Medical Subject Headings (MeSH)
  3. ^ Ghanem H et al. Combination clomiphene and antioxidant therapy for idiopathic male infertility: A randomized controlled trial. Fertil Steril 2009 Mar 5; [e-pub ahead of print]. Published in Journal Watch General Medicine March 31, 2009
  4. ^ Diergaarde, B., & Kurta, M. L. (2014). Use of fertility drugs and risk of ovarian cancer. Current opinion in obstetrics & gynecology, 26(3), 125-9
  5. ^ Kumar, P., Sait, S. F., Sharma, A., & Kumar, M. (2011). Ovarian hyperstimulation syndrome. Journal of human reproductive sciences, 4(2), 70-5
  6. ^ Multiple gestation pregnancy, Human Reproduction, Volume 15, Issue 8, 1 August 2000, Pages 1856–1864, https://doi.org/10.1093/humrep/15.8.1856
  7. ^ Schieve LA, Peterson HB, Meikle SF, et al. Live-birth rates and multiple-birth risk using in vitro fertilization. JAMA.1999;282 :1832– 1838