Fertility of ejaculated and testicular megalohead spermatozoa with intracytoplasmic sperm injection

In this study the fertility and outcome of intracytoplasmic sperm injection (ICSI) using megalohead spermatozoa from the ejaculates and testicles was evaluated. Seventeen males with megalohead and pinhead sperm forms in their ejaculate were studied in 22 cycles. A high number of sperm heads without tails and abundant round spermatid forms were commonly observed. Round-head ed spermatozoa were seldom accompanied by these severely abnormal spermatoz oa. The majority of megalohead spermatozoa were observed to have multiple t ails, were predominant in the sample, and were used for ICSI, Ejaculated me galohead spermatozoa were used for ICSI in 15 cycles, while testicular sper matozoa were used in seven cycles where there were no vital spermatozoa or spermatozoa of low vitality in the ejaculate. The same abnormal morphology was observed in the testicles as in the ejaculated spermatozoa in the same males. Mean (+/- SD) low motility 4.7 +/- 5.6% and sperm count (3.8 +/- 4.1 9 x 10(6)) were common findings in these severely teratozoospermic patients . A low fertilization rate (43.2%) was achieved by using megalohead sperm f orms (group I, n = 17) in comparison with the control group (60.2%) which h ad zero normal sperm morphology according to strict criteria (group II, n = 30) (P <0.01). Furthermore, a low pregnancy rate (9.1%) was obtained in th e megalohead sperm group in comparison with the control group (40%) (P <0.0 5). Low fertilization and pregnancy rates may be due to a high incidence of chromosomal abnormalities from severely defective spermatozoa in the ejacu late. Couples should be counselled and warned about possible low fertilizat ion and pregnancy rates with ICSI when only pinhead and megalohead forms wi th a high number of sperm heads without tails are present in the ejaculate.