[Influence of male age on the outcome of conventional IVF-ET]

To study the influence of male age on the outcome of conventional IVF-ET.

Based on male age, 170 couples undergoing conventional IVF-ET were divided into three groups: <35 yr (n = 60), 35 -39 yr (n = 77) and > or = 40 yr (n = 33). We observed the rates of fertilization, cleavage, good quality embryo, implantation, clinical pregnancy and abortion in different groups.

There were no significant differences among the three groups in semen volume ([3.10 +/- 1.22] ml vs [2.84 +/- 1.05] ml vs [2.80 +/- 0.79] ml), sperm concentration ([54.23 +/- 26.07] x 10(6)/ml vs [60.27 +/- 24.80] x 10(6)/ml vs [60.21 +/- 27.42] x 10(6)/ml) and sperm viability ([53.93 +/- 13.25]% vs [56.10 +/- 16.58]% vs [51.82 +/- 15.45]%) (P>0.05). The men of the > or = 40 yr group showed a significantly lower percentage of grade a + b sperm ([40.97 +/- 11.91]%) than those of the <35 and 35 - 39 yr groups ([48.47 +/- 11.78]% and [46.84 +/- 13.51]%) (P<0.05), and morphologically normal sperm ([11.76 +/- 5.97]%) than those of the <35 yr group ([15.25 +/- 6.94]% (P<0.05). The rates of fertilization, cleavage, good quality embryo, implantation, clinical pregnancy were 81.52%, 82.61%, 52.33%, 18.06% and 33.33% in the > or = 40 yr group, with no significant differences from those of the <35 yr group (83.18%, 82.68%, 56.99%, 22.40% and 40.00%) and the 35 - 39 yr group (78.78%, 80.66%, 55.01%, 21.74% and 38.96%) (P>0.05), while the abortion rate was markedly increased in the > or = 40 yr group as compared with the <35 yr group (36.36% vs 8.33%, P>0.05).

Increasing male age is related with decreasing percentages of progressively motile sperm and morphologically normal sperm, but not obviously with the rates of fertilization, good quality embryo, implantation, pregnancy and abortion.