Franco Lisi

Evaluation of 225 patients undergoing subzonal insemination for the procurement of fertilization in vitro

Objective To evaluate subzonal insemination for the procurement of fertilization in infertile males. Design The spermatozoa of infertile males was used, where possible, for in vitro fertilization (IVF) and subzonal insemination with the same cohort of oocytes obtained from their partner. Setting An individual unit in a general hospital, Clinica Nomentana, Rome, Italy. Patients Males who had repeatedly failed to achieve conception in vitro by IVF or in whom seminal parameters were unacceptable for IVF were treated. Interventions Two hundred twenty-five transvaginal oocyte retrievals were performed. Main Outcome Measures The incidence of fertilization, cleavage, and pregnancy was evaluated in relation to the numbers of spermatozoa injected and the individual spermatozoa parameters. Results Fertilization occurred in 39% of patients and 16% of eggs, and 12 clinical pregnancies were established. Fertilization increased with increasing numbers of spermatozoa injected. Fertilization with subzonal insemination was significantly greater (39%) than after in vitro insemination (6%) ( P Conclusions Subzonal insemination improved the incidence of fertilization in this series of patients, and a new classification of spermatozoa based on total motile count aided prognosis for fertilization.

Subzonal insemination and zona breaching techniques for assisting conception in vitro

The following comments can be made with regard to zona breaching procedures (PZD) and SUZI. First and foremost, it is important to establish that fertilization cannot occur with microdrop IVF or conventional IVF before proceeding with microassisted fertilization technology. PZD increases the rate of polyspermy, and this is significantly higher than when utilizing SUZI. SUZI increases the incidence of implantation in cases exhibiting severe teratozoospermia. SUZI increases the fertilization rate per patient and per oocyte in cases where IVF has previously failed on more than one occasion. SUZI increases the incidence of fertilization when very few motile sperm are available, and there is an increase in the incidence of cytoplasmic fragmentation with SUZI, which might be alleviated by improving methods of penetrating the zona pellucida, for example by using the Sonic Sword or utilizing a thinner, sharper injection needle alone or in addition to increasing the perivitelline space by dehydrating the oocyte (Yang et al, 1988). Morphology is an important parameter in predicting the outcome of IVF and therefore in guiding patients on the relevance of microinjection technology.