title: Time of insemination and its effect on in-vitro fertilization, cleavage and pregnancy rates in GnRH agonist/HMG-stimulated cycles.
abstract: In this prospective study, we compared the effect of delayed inseminations on fertilization, cleavage and pregnancy rates in two groups of patients. In one group, the ovarian stimulation was performed with a clomiphene citrate/human menopausal gonadotrophin/human chorionic gonadotrophin (CC/HMG/HCG) protocol. The other group was pre-treated with gonadotrophin-releasing hormone agonist (GnRHa) and ovarian stimulation was carried out with an HMG/HCG protocol. Under both protocols, a delay of 2, 4 or 6 h in insemination showed no significant differences in the fertilization, cleavage or pregnancy rates. To find out which type of oocyte has the potential for better fertilization, cleavage and implantation, a simple oocyte classification scheme is proposed. In the GnRHa/HMG group, 9% post-mature, 90% mature and only 1% immature oocytes were retrieved. The post-mature oocytes showed a tendency towards reduced fertilization when insemination was delayed. The mature and slightly immature oocytes fertilized equally well when spermatozoa were added 2, 4 or 6 h after retrieval. Similarly, no significant difference was observed in the cleavage (80%) or fragmentation (20%) rates of these oocytes. The pregnancy rates after inseminations delayed for 2, 4 and 6 h were 14, 27 and 26%, respectively. Though these figures were not statistically significant, the 4- and 6-h groups in both the IVF and zygote intra-Fallopian transfer treatments showed a slightly improved pregnancy rate compared to the 2-h group. An insemination delay of 4 h is advocated on a routine basis.
authors.affiliation: Centre for Reproductive Medicine, Academic Hospital, Vrije Universiteit Brussel, Belgium.
authors.forename: I
authors.initials: I
authors.lastname: Khan
authors.forename: C
authors.initials: C
authors.lastname: Staessen
authors.forename: E
authors.initials: E
authors.lastname: Van den Abbeel
authors.forename: M
authors.initials: M
authors.lastname: Camus
authors.forename: A
authors.initials: A
authors.lastname: Wisanto
authors.forename: J
authors.initials: J
authors.lastname: Smitz
authors.forename: P
authors.initials: P
authors.lastname: Devroey
authors.forename: A C
authors.initials: AC
authors.lastname: Van Steirteghem
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000494:pharmacology*; D002970:Cleavage Stage, Ovum / Q000187:drug effects; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007314:Insemination; D008297:Male; D008596:Menotropins / Q000494:pharmacology*; D008597:Menstrual Cycle / Q000187:drug effects; D009865:Oocytes / Q000187:drug effects; D010062:Ovulation Induction; D010906:Pituitary Hormone-Releasing Hormones / Q000502:physiology; D011247:Pregnancy; D011446:Prospective Studies; D013997:Time Factors
chemical_list: D006063:Chorionic Gonadotropin; D010906:Pituitary Hormone-Releasing Hormones; D008596:Menotropins