Ovulation vitro

Purified FSH is used to prepare follicles for in vitro fertilization because LH activity in menotropins may cause premature ovulation. Purified FSH is also used to treat infertility in women with polycystic ovarian disease in this disease LH and androgen production may already be elevated. 

In infertile women choosing in vitro fertilization, naferelin in combination with gonadotrophins can be used for stimulating ovulation. It is also useful in management of uterine leiomyoma, benign prostatic hypertrophy, hirsutism and polycystic ovarian syndrome. 

FSH, LH, and hCG are commercially available in several forms. They are used in states of infertility to stimulate spermatogenesis in men and to induce ovulation in women. Their most common clinical use is for the controlled ovulation hyperstimulation that is the cornerstone of assisted reproductive technologies such as in vitro fertilization (IVF, see below). 

Macklon NS et al The science behind 25 years of ovulation stimulation for in vitro fertilization. Endocr Rev 2006 27 170. [PMID 16434510]... 

Loumaye EEuropean Recombinant LH Study Group. Human recombinant luteinizing hormone is as effective as, but safer than, urinary human chorionic gonadotropin in inducing final follicular maturation and ovulation in in vitro fertilization procedures results of a multicenter double-blind study. J Clin Endocrinol Metab 2001 86(6) 2607-18. 

Cetrorelix is a synthetic decapeptide that reversibly binds to pituitary GnRH receptors without activating them. Cetrorelix thus inhibits the secretion of FSH and LH in a dose-dependent manner by competing with natural hypothalamic GnRH for pituitary cell surface receptors. At the doses used for in vitro fertilization, cetrorelix produces an immediate suppression of LH this delays the LH surge and thus delays ovulation. At higher doses, cetrorelix also suppresses FSH secretion, thus inhibiting the secretion of estradiol from the ovaries. 

In hypothalamic hypogonadism and for in vitro fertilization, one or two ampules are administered daily for 5-12 days until evidence of adequate follicular maturation is present. Serum estradiol levels should be measured and a cervical examination performed every 1 or 2 days. When appropriate follicular maturation has occurred, hMG or FSH is discontinued the following day, hCG (5000-10,000 IU) is administered intramuscularly to induce ovulation. 

Jl. Jackson, K. V., Ginsburg, E. S., Hornstein, M. D., Rein, M. S., and Clarke, R. N., Multinucleation in normally fertilized embryos is associated with an accelerated ovulation induction response and lower implantation and pregnancy rates in in vitro fertilization-embryo transfer cycles. Fertil. Steril. 70, 60-66 (1998). 

Ovaries perfused in vitro are useful systems for studying the mechanical aspects of ovulation. The preparations allow observations on the effects of agents in preventing rupture of the follicle and expulsion of the oocyte. The perfusion system is artificial, however, and the relocation of the ovary from peritoneal cavity to the perfusion chamber can alter the mechanical features of the system. For this reason, data from perfusion studies are not, in themselves, sufficient for drawing conclusions about an agent s reproductive toxicity. 

PTX-2 inhibited cytokinesis in mammalian ovulated oocytes and induced apoptosis in p53-deficient tumours both in vivo and in vitro (Chae et al. 2005). The authors found that treatment with PTX-2 influenced proteins involved in apoptosis in p53-deficient cells. PTX-2 displayed potent cytotoxity, with LC q values as low as 6.7 pg/mL, to a wide range of human cancer cell lines in vitro (Jung et al. 1995). The authors also presented evidence that PTX-2 did not block oxidation-reduction processes in the membrane or block DNA synthesis in vitro. 

In addition to the usefulness of DIA as a predictor of Down syndrome risk discussed previously, inhibin A and B measurements have found applications in ovarian cancer monitoring, disorders of ovulation, early detection of viable pregnancy following in vitro fertilization, and evaluation of male infertility. 

Pregnancy in the monkey was terminated at a time when the ovaries are required for the continuation of pregnancy as well as when the placenta is capable of maintaining pregnancy in the absence of the ovaries. The estrogen synthetase blocker inhibited mating, ovulation, and implantation in rats.38 of a series of aromatase inhibitors, 23 was the most active in vitro.39... 

Kugu, K Dharmarajan, A.M., Preutthipan, S., and Wallach, E.E. (1995). Role of calcium/calmodulin-dependent protein kinase 11 in gonadotrophin-induced ovulation in in-vitro-perfused rabbit ovaries. J. Reprod. Fert. 103 213-21%. 

Cetrorelix is used for the prevention of premature ovulation in women undergoing controlled ovarian stimulation in in vitro fertilization protocols. LH-RH antagonists suppress the LH levels and delay the occurrence of the preovulatory LH surge. 

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