title: Comparison of a fixed and dynamic protocol for embryo replacement in an IVF/ET programme.
abstract: Implantation after embryo transfer is considered a major obstacle in terms of pregnancy rates after in-vitro fertilization. A flexible approach to the date of replacement, based on the fact that the most suitable embryonic structure for proper implantation is the four- to eight-cell embryo, has been studied. One-hundred-and-twenty patients with various aetiologies of infertility were stimulated with HMG or combined HMG and FSH, then treated by three different methods of embryo replacement. In group I embryos were replaced in mothers 48 h after ovum retrieval; in group II replacements were carried out 72 h after retrieval; and in group III replacements were related to embryonic cleavage development. Mean levels of oestradiol when HCG was given averaged 1301 +/- 121 pg/ml, 1016 +/- 96 pg/ml and 1182 +/- 101 pg/ml in the three groups, respectively. There was no significant difference in the average number of embryos transferred among the various groups. The pregnancy rates per transfer were 21.8, 24.2 and 38.7%, respectively (P less than 0.001). Although more investigation is required, a dynamic approach to embryo replacement might significantly improve pregnancy rates, because of improved interactions between the embryos and the uterus.
authors.affiliation: Sherman Fertility Institute, Department of Obstetrics and Gynaecology, Golda Meir Medical Centre, (Hasharon Hospital), Petach-Tikva, Israel.
authors.forename: D
authors.initials: D
authors.lastname: Feldberg
authors.forename: J A
authors.initials: JA
authors.lastname: Goldman
authors.forename: M
authors.initials: M
authors.lastname: Shelef
authors.forename: J
authors.initials: J
authors.lastname: Ashkenazi
authors.forename: D
authors.initials: D
authors.lastname: Dicker
authors.forename: A
authors.initials: A
authors.lastname: Yeshaya
mesh_terms: D006063:Chorionic Gonadotropin / Q000627:therapeutic use; D004359:Drug Therapy, Combination; D004624:Embryo Transfer / Q000379:methods*; D004958:Estradiol / Q000097:blood; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D005640:Follicle Stimulating Hormone / Q000627:therapeutic use; D006801:Humans; D008596:Menotropins / Q000627:therapeutic use; D009865:Oocytes / Q000166:cytology; D013997:Time Factors
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol; D008596:Menotropins; D005640:Follicle Stimulating Hormone