ObjectiveDespite higher sperm DNA fragmentation may affect intracytoplasmic sperm
injection (ICSI) outcomes, sperm selection protocols do not evaluate this
parameter. Therefore, sperm’s head birefringence has been suggested as an
adjuvant of seminal processing to select viable sperm for couples with
severe male factor. Considering men with normal seminal parameters may also
curse with DNA fragmentation, the aim of this study was to evaluate the
impact of sperm selection by birefringence on ICSI outcomes in couples with
different infertility factors compared to those submitted to conventional
sperm selection.MethodsIn this case-control study, medical records from 181 couples who underwent
ICSI from January 2018 to August 2020 (107 from the Conventional and 74 from
the Birefringence group) were included in the study. Clinical
characteristics and ICSI outcomes were compared between the groups using
Student’s t test or Chi-square test (p<0.05) and a
multivariate logistic regression model was applied regarding clinical
pregnancy.ResultsDespite the Birefringence group showed higher female age
(p=0.01), lower seminal sperm concentration
(p<0.01) and higher sperm DNA fragmentation
(p<0.01), those patients cursed with both higher
cleavage rate (p=0.04), clinical pregnancy rate per
transfer (p=0.03) and clinical pregnancy rate per initiated
cycle (p=0.02). The logistic regression showed a positive
group effect on clinical pregnancy.ConclusionsThe findings suggest a positive clinical impact of this cheap and easily
reproducible adjuvant technique on ICSI outcomes in couples with different
infertility factors. If confirmed by further methodologically appropriate
studies, the sperm’s head birefringence could be considered to improve the
reproductive chances of those patients.