THE RELATIONSHIP BETWEEN SPERM MORPHOLOGY AND RATES OF FERTILIZATION,PREGNANCY AND SPONTANEOUS-ABORTION IN AN IN-VITRO FERTILIZATION INTRACYTOPLASMIC SPERM INJECTION PROGRAM

The morphological normality of a spermatozoon is considered to be an i mportant factor in relation to its ability to fertilize an oocyte, We examined the influence of morphology (strict criteria) on the rates of fertilization, pregnancy and spontaneous abortion obtained following conventional in-vitro fertilization (IVF) and intracytoplasmic sperm i njection (ICSI) in our clinical programme. We found our fertilization cut-off values for conventional IVF to be slightly different from thos e of the Kruger group (10 and 5%, compared to 14 and 5%). We also foun d the pregnancy rate per transfer to be as good or better in the group s with <5% normal forms: 36% of these men had a fertilization rate >50 % using conventional IVF, showing that fertilization capacity is not n ecessarily impaired even in this 'poor prognosis' group. With the exce ption of the ICSI group with 5-9% normal forms, the rate of spontaneou s abortion in this study was similar to or lower than in our IVF/ICSI programme overall. When the 5-9% normal spermatozoa group was divided into those with teratozoospermia as the only factor and those with add itional sperm factors, the increased abortion rate was found in the gr oup with multiple sperm factors (67% spontaneous abortions).