Effects of phototherapy on newborn rat testicles.

Phototherapy is the most widespread treatment for lowering bilirubin concentration in neonates. In the routine, phototherapy has some side effects including skin eruption, fluid loss, abdominal distention, mild hemolysis and mild thrombocytopenia. The aim of the study was to investigate the possible mutagenic and gametocidal side effects of 72 h continuous phototherapy on the rat testicle. We observed decreases in spermatogonia numbers per tubule (S/T values), tubular fertilization index (TFI) and sperm sertoli cell index (SSCI), which are the most reliable methods in estimating future fertility potential, due to sensitivity to phototherapy. The differences between study and control groups for S/T, TFI and SSCI values were statistically significant (p = 0.008, p = 0.02 and p = 0.004, respectively). There were significant differences in seminiferous tubule diameters between the control and study groups (p < 0.005), but no significant difference in DNA index values between the control (0.66 +/- 0.12) and study (0.59 +/- 0.05) groups (p > 0.05). As a conclusion, phototherapy seems to have some side effects on the newborn rat testicle. Further studies with larger groups, designed for investigation of the effects of phototherapy on seminiferous tubules, may give more beneficial results.