Gametes intrauterine transfer versus in vitro fertilization for poor responders

Fertilization in the human takes place in the fallopian tube. However, pregnancies have been reported following direct intra-uterine transfer of oocytes and sperm (gametes intrauterine transfer, GIUT) [1–3], indicating that the uterus is permissible, though may not be optimal, for fertilization. During a routine in vitro fertilization and embryo transfer (IVF-ET) treatment cycle, embryos are usually cultured in vitro for 2–5 days so that embryos of best quality can be selected for transfer. If the patient has too few embryos to allow for selection, GIUT may be performed, which avoids prolonged exposure of embryos to potentially harmful in vitro conditions [4]. The objective of this prospective study was to assess the effectiveness of GIUT in establishing pregnancies in patients with a low yield of oocytes. All patients in this study were initially prepared for IVF-ET because of tubal-factor infertility. Controlled ovarian stimulation protocol consisted of LHRH-agonist suppression followed by gonadotropin treatments. If the number of oocytes retrieved was five or less, the patients were randomly divided (assignment to IVF or GIUT was concealed in envelopes that were opened in a random order for each patient) between IVF and GIUT after informed consent was obtained from each participating patient. In the IVF treatment group, fertilization was achieved by culturing oocytes with motile sperm overnight in HTF medium, and embryo transfer was performed on day 3. In the GIUT treatment group, oocytes were transferred to the uterine cavity together with 300,000 motile sperm 3 h after oocyte retrieval. Clinical pregnancy was confirmed sonographically by the presence of fetal cardiac activity. Statistical analysis was performed using t-test or Chi-squared test. None of the demographic or clinical parameters differed significantly between GIUT and IVF cycles (Table 1). Clinical pregnancy rates were similar between GIUT and IVF groups. Early reports of GIUT yielded little information concerning its efficacy in comparison with IVF [1–3]. The present study indicates that GIUT can result in treatment outcome very similar to IVF for patients with low number of oocytes retrieved. Intrauterine transfer of gametes has some advantages over gametes intra-fallopian transfer because the latter is a more complex surgical procedure and cannot be used in patients with bilateral tubal disorders. Thus, GIUT may be used as an alternative to IVF for poor responders, as well as for those patients to whom IVF is not acceptable due to religious constraints.