title: The optimal length of 'coasting protocol' in women at risk of ovarian hyperstimulation syndrome undergoing in vitro fertilization.
abstract: Ovarian hyperstimulation syndrome (OHSS) is a serious and potentially life-threatening complication following ovarian stimulation for in vitro fertilization (IVF). Coasting is the practice whereby the gonadotrophins are withheld and the administration of human chorionic gonadotrophin (hCG) is delayed until serum oestradiol (E2) has decreased to what is considered to be a safe level, to prevent the onset of OHSS. This study aimed to assess the length of coasting on the reproductive outcome in women at risk of developing OHSS. Coasting was undertaken when the serum E2 concentrations were > or = 17000 pmol/L but < 21000 pmol/L. Daily E2 measurements were performed and hCG was administered when hormone levels decreased to < 17000 pmol/L. Eighty-one women who had their stimulation cycles coasted were grouped according to the number of coasting days. Severe OHSS occurred in one case, which represented 1.2% of patients who underwent coasting because of an increased risk of developing the syndrome. No difference was found between cycles coasted for 1 - 3 days and cycles coasted for > or = 4 days in terms of oocyte maturity, fertilization and embryo cleavage rates. Women in whom coasting lasted for > or = 4 days had significantly fewer oocytes retrieved (P < 0.05) and decreased implantation rate (P < 0.05) compared to those coasted for 1 - 3 days. Pregnancy rate/embryo transfer and live birth rate did not differ between groups. In conclusion, coasting appears to decrease the risk of OHSS without compromising the IVF cycle pregnancy outcome. Prolonged coasting is, however, associated with reduced implantation rates, perhaps due to the deleterious effects on the endometrium rather than the oocytes.
authors.affiliation: Department of Reproductive Medicine, Saint Mary's Hospital, Whitworth Park, Manchester, UK. Luciano.Nardo@cmmc.nhs.uk
authors.forename: Luciano G
authors.initials: LG
authors.lastname: Nardo
authors.forename: Priya
authors.initials: P
authors.lastname: Cheema
authors.forename: Tarek A
authors.initials: TA
authors.lastname: Gelbaya
authors.forename: Greg
authors.initials: G
authors.lastname: Horne
authors.forename: Cheryl T
authors.initials: CT
authors.lastname: Fitzgerald
authors.forename: Elizabeth H E
authors.initials: EH
authors.lastname: Pease
authors.forename: Daniel R
authors.initials: DR
authors.lastname: Brison
authors.forename: Brian A
authors.initials: BA
authors.lastname: Lieberman
mesh_terms: D006063:Chorionic Gonadotropin / Q000008:administration & dosage; D002985:Clinical Protocols; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro / Q000009:adverse effects* / Q000379:methods*; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D008596:Menotropins / Q000008:administration & dosage; D016471:Ovarian Hyperstimulation Syndrome / Q000209:etiology / Q000517:prevention & control*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D012307:Risk Factors; D020554:Sperm Injections, Intracytoplasmic / Q000009:adverse effects / Q000379:methods; D013997:Time Factors
chemical_list: D006063:Chorionic Gonadotropin; D007987:Gonadotropin-Releasing Hormone; D004958:Estradiol; D008596:Menotropins