Is fine morphology of the human sperm nuclei affected by in vitro incubation at 37 degrees C?
OBJECTIVE: Incubation of ejaculated spermatozoa at 37 degrees C is recommended for IVF-intracytoplasmic sperm injection. Preselection of sperm cells with morphologically normal nuclei before microinjection, adapted in our laboratory, is usually a time-consuming procedure. Therefore, we aimed to verify whether incubation at 37 degrees C could affect the morphologic integrity of sperm nuclei. DESIGN: Time-kinetics studies testing fine morphology of the sperm nuclei upon prolonged in vitro incubation. SETTING: Male Fertility Laboratory at Bar-Ilan University, Ramat Gan, Israel. PATIENT(S): Forty-two males selected at random, who were referred for sperm preselection before ICSI. MAIN OUTCOME MEASURE(S): Morphologic integrity of the sperm nuclei, obtained by motile sperm organelle morphology examination. RESULT(S): After 2 hours of incubation at 37 degrees C a significant decrease occurred in the morphologic integrity of the sperm nuclei, compared with the initial state (4.7% +/- 2.8% vs. 6
