Uterine vascularization and pregnancy outcome in patients undergoing intracytoplasmatic sperm injection: the role of nitric oxide

Purpose: To evaluate whether, after pituitary desensitisation, the impedance to flow in the uterine vessels may be an indicator of an ICSI programme outcome, and to test the relationship between intrafollicular nitric oxide and oocyte/embryo quality. Methods: Thirty-eight women, on the basis of impedance to flow at the level of uterine artery, evaluated on the first day of COH, were divided in patients with normal (Pulsatility Index-PI, <= 2.5; Group I, n=11) and elevated (PI > 2.5; Group II, n=27) PI values. The patients were submitted to hormonal, ultrasonographic and Doppler evaluations. Plasma and follicular fluid concentrations of nitrites/nitrate (NO2-/NO3-) were assayed. Results: In the Group I, the impedance to flow remained lower than in Group II and was associated to good quality embryos and to a higher pregnancy rate. Follicular fluid NO2-/NO3- levels were inversely correlated with the embryo quality. The uterine artery PI and the pregnancy rate were inversely correlated. The PIs analysed on the day 1 of stimulation, were positively correlated with those registered on day 8 and on the day of ovum pick-up. Conclusions: A Doppler analysis done on day 1 of controlled ovarian hyperstimulation may be an useful indicator of ART outcome.