title: Variation of DNA Fragmentation Levels During Density Gradient Sperm Selection for Assisted Reproduction Techniques: A Possible New Male Predictive Parameter of Pregnancy?
abstract: Predicting the outcome of in vitro fertilization (IVF)/intracytoplasmic sperm injection (ICSI) is one main goal of the present research on assisted reproduction. To understand whether density gradient centrifugation (DGC), used to select sperm, can affect sperm DNA integrity and impact pregnancy rate (PR), we prospectively evaluated sperm DNA fragmentation (sDF) by TUNEL/PI, before and after DGC. sDF was studied in a cohort of 90 infertile couples the same day of IVF/ICSI treatment. After DGC, sDF increased in 41 samples (Group A, median sDF value: 29.25% [interquartile range, IQR: 16.01-41.63] in pre- and 60.40% [IQR: 32.92-93.53] in post-DGC) and decreased in 49 (Group B, median sDF value: 18.84% [IQR: 13.70-35.47] in pre- and 8.98% [IQR: 6.24-15.58] in post-DGC). PR was 17.1% and 34.4% in Group A and B, respectively (odds ratio [OR]: 2.58, 95% confidence interval [CI]: 0.95-7.04, P = 0.056). After adjustment for female factor, female and male age and female BMI, the estimated OR increased to 3.12 (95% CI: 1.05-9.27, P = 0.041). According to the subgroup analysis for presence/absence of female factor, heterogeneity in the association between the Group A and B and PR emerged (OR: 4.22, 95% CI: 1.16-15.30 and OR: 1.53, 95% CI: 0.23-10.40, respectively, for couples without, n = 59, and with, n = 31, female factor).This study provides the first evidence that the DGC procedure produces an increase in sDF in about half of the subjects undergoing IVF/ICSI, who then show a much lower probability of pregnancy, raising concerns about the safety of this selection procedure. Evaluation of sDF before and after DGC configures as a possible new prognostic parameter of pregnancy outcome in IVF/ICSI. Alternative sperm selection strategies are recommended for those subjects who undergo the damage after DGC.
authors.affiliation: From the Department of Experimental, Clinical and Biomedical Sciences, Unit of Sexual Medicine and Andrology, Center of Excellence DeNothe, University of Florence (MM, MC, ALI, CP, BL, SM, LT, GF, MM, EB); Tecnobios Procreazione, Centre for Reproductive Health, Bologna (NT, MN, AB); and Clinical Trials Coordinating Center, AOU Careggi, Istituto Toscano Tumori, Florence (LB), Italy.
authors.forename: Monica
authors.initials: M
authors.lastname: Muratori
authors.forename: Nicoletta
authors.initials: N
authors.lastname: Tarozzi
authors.forename: Marta
authors.initials: M
authors.lastname: Cambi
authors.forename: Luca
authors.initials: L
authors.lastname: Boni
authors.forename: Anna Lisa
authors.initials: AL
authors.lastname: Iorio
authors.forename: Claudia
authors.initials: C
authors.lastname: Passaro
authors.forename: Benedetta
authors.initials: B
authors.lastname: Luppino
authors.forename: Marco
authors.initials: M
authors.lastname: Nadalini
authors.forename: Sara
authors.initials: S
authors.lastname: Marchiani
authors.forename: Lara
authors.initials: L
authors.lastname: Tamburrino
authors.forename: Gianni
authors.initials: G
authors.lastname: Forti
authors.forename: Mario
authors.initials: M
authors.lastname: Maggi
authors.forename: Elisabetta
authors.initials: E
authors.lastname: Baldi
authors.forename: Andrea
authors.initials: A
authors.lastname: Borini
mesh_terms: D000328:Adult; D002499:Centrifugation, Density Gradient; D053938:DNA Fragmentation; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000628:therapy; D007248:Infertility, Male / Q000628:therapy; D008297:Male; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D012372:ROC Curve; D020554:Sperm Injections, Intracytoplasmic; D013094:Spermatozoa