We have dissected the initial stages of fertilization by intracytoplasmic sperm injection of single spermatozoa into prime oocytes from fertile rhesus monkeys (Macaca mulatta). DNA decondensation was delayed at the apical portion of the sperm head. It is possible that this asynchronous male DNA decondensation could be related to the persistence of the sperm acrosome and perinuclear theca after ...

OBJECTIVE To evaluate the role of hyaluronic acid (HA) for sperm selection before intracytoplasmic sperm injection (ICSI). DESIGN Three prospective studies. SETTING Private assisted reproduction center in Italy. PATIENT(S) Study 1: 20 men. Study 2: 15 men. Study 3: 206 couples treated with ICSI on a limited number of oocytes per patient (1-3) in accordance with Italian IVF law. INTERVEN...

The ICSI has become method of choice to achieve fertilization. Fertilization is possible in cases in which the sperm motility and ability to penetrate the zona pellucida are impaired. Injection is possible with sperm obtained from ejaculation, microsurgical epididymal sperm aspiration (MESA), percutaneous epididymal sperm aspiration (PESA), or testicular sperm extraction (TESE). In addition, in...