The efficiency of cryopreserved semen versus fresh semen for in vitro fertilization/embryo transfer

The efficiency of cryopreserved donor semen versus fresh donor semen in an in vitro fertilization/embryo transfer programme was evaluated. Thirty-nine in vitro fertilization/embryo transfer cycles were performed using fresh donor semen (group A) and 74 cycles were carried out using cryopreserved semen (group B). All patients underwent a uniform controlled ovarian hyperstimulation using high doses of human menopausal gonadotropins. Oocytes were retrieved transvaginally under ultrasound imaging. Semen (fresh or frozen-thawed) were prepared for insemination by a washing technique. Each ovum was inseminated with 500,000-600,000 motile spermatozoa. No significant difference was noted between the two groups regarding female age, duration of infertility, and number of ova retrieved per aspiration. Even though the fertilization rate in group B was significantly lower than in group A (55.5 +/- 3.8 vs 70.4 +/- 3.5, P = 0.008), pregnancy rates per embryo transfer were similar--39.3 and 38.5%, respectively.