RESUMO
BACKGROUND: Nitric oxide (NO) is involved in local control of the uterine cycle and in preparation of the uterus for pregnancy. NO donors, acting as vasodilating agents, may therefore have possible therapeutic uses, for example they may be of benefit to patients with a history of implantation failure. In a prospective, comparative, randomized, placebo-controlled study, we assessed the efficacy of nitroglycerin (NTG) administered to 138 IVF patients with a history of implantation failure. METHODS: Controlled ovarian stimulation was performed with long agonist protocol combined with recombinant FSH. Embryos were transferred on day 2 or 3 after oocyte retrieval. Eligible patients were those who had at least two 'good quality' embryos. The NTG patch was administered the day before embryo transfer and continued until either the results of the pregnancy test were known or until menstruation occurred. RESULTS: Ovarian response, implantation rate and pregnancy rate were comparable between both groups. No difference was observed in uterine Doppler findings, particularly the mean pulsatility index. CONCLUSIONS: NTG treatment the day before embryo transfer was no more effective than placebo in improving the implantation or pregnancy rates in a population of IVF patients with a previous history of implantation failures.
