Pentoxifylline-enhanced acrosome reaction correlates with fertilization in vitro.

To evaluate the possible effect of pentoxifylline on the acrosome reaction (AR) and its correlation with in-vitro fertilization (IVF), sperm samples obtained from 51 patients who underwent IVF treatment were studied. Acrosome reactions were evaluated as spontaneous, pentoxifylline-treated and calcium ionophore (A23187) induced, before and after treatment. The correlation of AR with fertilization in vitro in spermatozoa pre-treated with pentoxifylline was sought. In cases with failure or very low fertilization rate (< or = 10%) in their previous trials, spermatozoa after swim-up were treated before insemination. Spontaneous acrosome loss remained low even after treatment (mean +/- SD: 8.18 +/- 1.74%). Response to A23187 was enhanced significantly (P < 0.001) by pre-treatment with pentoxifylline in 33 control cases (group A) in which fertilization in vitro was previously successful without this treatment. Patients with at least two episodes of failed fertilization were divided into two groups. In 11 cases (group B), the IVF rate was improved significantly (P < 0.001) by the treatment. This was not observed in seven cases (group C) in which the treatment induced no increase in IVF rate. We achieved nine (27.3%) pregnancies in group A and five (45.4%) pregnancies in group B. This study demonstrated that pentoxifylline enhanced A23187 induced the acrosome reaction and this effect was correlated with improvement in IVF rate.