A COMPARATIVE-ANALYSIS OF EMBRYO IMPLANTATION POTENTIAL IN PATIENTS WITH SEVERE TERATOZOOSPERMIA UNDERGOING IN-VITRO FERTILIZATION WITH A HIGH INSEMINATION CONCENTRATION OR INTRACYTOPLASMIC SPERM INJECTION

The objective of this study was to assess fertilization, implantation and pregnancy rates in infertile patients with severe teratozoospermia [P (poor prognosis) pattern sperm morphology assessed by strict crite rial treated by in-vitro fertilization (IVF) using a high insemination concentration (HIC), or by intracytoplasmic sperm injection (ICSI), T his was a retrospective cohort study performed in an academic tertiary institution, The outcome of 115 consecutive ICSI cycles was compared to that of a similar number of cycles of IVF with HIC performed during a similar time frame and matched by woman's age and basal serum (cycl e day 3) follicle stimulating hormone concentrations. The inclusion cr iteria were sperm morphology less than or equal to 4% normal forms (P pattern) and greater than or equal to 1x10(6) total motile spermatozoa per ejaculate. The diploid fertilization rate in the HIC-IVF group wa s 86% and in the ICSI group 68% (P < 0.05), Importantly, an equal numb er of embryos was transferred to both groups of patients, The morpholo gical quality of the embryos (proportion of transfers having superior morphology embryo scores) was significantly better in the ICSI group t han in the patients receiving HIC-IVF, Although there was a clear tren d for better implantation and pregnancy rates in the ICSI group, these differences were not statistically significant, We conclude that, alt hough HIC-IVF resulted in a higher fertilization rate than ICSI in pat ients with severe teratozoospermia, ICSI produced a significantly high er proportion of morphologically superior embryos with a tendency towa rds a higher implantation potential, Therefore, teratozoospermic patie nts having adequate numbers of motile spermatozoa should be offered IC SI as an alternative to modified (HIC) NF treatment.