Comparison of two ready-to-use systems specially designed for physiological intracytoplasmic sperm injection (ICSI): PICSI® versus Sperm Slow™, a prospective randomised trial

INTERVENTION: 100 ICSI treatments randomly carried out with PICSI® Sperm Selection Device or with Sperm Slow™ for sperm selection. Randomisation process conducted with sealed envelopes, assigning 50 subjects to each treatment group. Controlled ovarian stimulation with gonadotropin‐releasing hormone analogs in combination with a graded gonadotropin administration. Oocyte retrieval performed 35 hours after ovulation induction with either 5,000 or 10,000 IU of human chorionic gonadotropin (hCG). Oocytes culture at 37°C in an atmosphere of 6% CO2. Complete removal of cumulus mass and corona cells by enzymatic digestion of recombinant hyaluronidase (SynVitro® Cumulase® MediCult) and by gentle mechanical aspiration with plastic pipettes (Stripper Tips® MidAtlantic Diagnostic). Assessment of the nuclear maturation stage of the denuded oocytes. Strict selection of the metaphase II oocytes (MII) by morphological features (zona pellucida thickness, perivitelline space size, oocyte shape, cytoplasm colour and granularity, presence of vacuoles and first polar body morphology) under an inverted microscope with Hoffman modulation contrast. Classification of "high quality oocytes": colourless and of regular shape, with regular zona pellucida and small perivitelline space without debris, homogeneous cytoplasm and no vacuoles or granulations. Insemination by ICSI of the best available MII oocytes, in accordance with the Italian law regulating Assisted Reproductive Technology (cryopreservation of the supernumerary MII oocytes reaching the "high quality" standards). PICSI® Sperm Selection Device procedure as described in www.midatlanticdiagnostics.com. Sperm Slow™ ICSI procedure: Spermatozoa must first be treated with a two‐layer density gradient system or via Swim‐Up. Thus, on a Petri dish, a 2 µL droplet with suspension of treated spermatozoa is connected with a pipette tip to a 5 µL droplet fresh culture medium (Sperm Preparation Medium, MediCult). Simultaneously, A 5 µL droplet of HA‐co CONDITION: Intracytoplasmic sperm injection (ICSI) ; Pregnancy and Childbirth ; Fertility PRIMARY OUTCOME: 1. Oocyte fertilisation rate, measured 15 ‐ 22 hours after oocyte insemination; 2. Embryo cleavage rate, measured at day of embryo transfer (2, 3 or 5 days after oocyte insemination); 3. Top‐quality embryo rate, measured at day of embryo transfer (2, 3 or 5 days after oocyte insemination) ; 4. Pregnancy rate, measured 30 days after the embryo transfer; 5. Implantation rate, measured 30 days after the embryo transfer SECONDARY OUTCOME: Duration of ICSI procedure, measured at time of oocyte insemination INCLUSION CRITERIA: 1. Infertile women not older than 41 years undergoing ICSI treatment at GynePro Medical Center 2. Semen parameters of the male partner: 2.1. Presence of ejaculate motile spermatozoa with total sperm number greater than or equal to 1,000,000 2.2. Sperm motility greater than or equal to 5%