Randomized trial of partial zona dissection for male infertility

Abstract

To compare IVF rates using partial zona dissection versus zona intact insemination in couples with male infertility. To analyze pregnancy rates relative to sperm characteristics, fertilization rates, and treatment. Randomized prospective comparison of fertilization in sibling oocytes. Transfer of the three best quality embryos from one or both treatments. Department of Gynaecology and Reproductive Medicine, University Hospital, London, Ontario, Canada. Thirty-two couples undergoing IVF with a principal diagnosis of male infertility. Treatment with partial zona dissection. Fertilization and pregnancy. Fertilization rates were 26% and 9% after partial zona dissection and IVF, respectively. Polyspermy was < 1% in each treatment. There were five singleton pregnancies in 29 completed cycles, three in cycles with fertilization only by partial zona dissection and two in cycles with both partial zona dissection and IVF fertilization. There were no pregnancies after fertilization by IVF only. Stepwise logistic regression analysis indicated that pregnancy was related to partial zona dissection, initial sperm concentration, and total acrosin activity. Partial zona dissection was associated with minimal polyspermic fertilization and higher normal fertilization rates than sibling oocytes treated by modified IVF. Pregnancy occurred only after transfer of embryos from partial zona dissection or combined partial zona dissection and IVF.