Analysis of the factors relevant to pregnancy rate of intra-uterine insemination with husband's semen

Objective: To study the factors affecting the pregnancy rate per intra-uterine insemination(IUI) cycle in order to improve the outcome of IUI.Methods: The data from 168 infertility couples who underwent IUI cycles in our reproductive medicine center during January,2004 and December,2005 were retrospectively analyzed.A total of 286 cycles were recorded.Multiple indices were analyzed,including the age of the patient,duration of infertility,causes and types(primary or secondary) of infertility,methods for ovulation induction,IUI procedure,sperm count and grade.Results: The pregnancy rate per IUI cycle for the women aged over 35 years was significantly lower than that of others(8.9% vs.26.3%,25.2% and 22.2% for the women aged 21-25 years,25-30 years and 30-35 years,respectively,P0.05).The pregnancy rate per IUI cycle in the women with 3-4 years(16.0%) or more than 4 years of infertility(10.9%) was significantly reduced when compared with that in women with 1-2 years(26.3%) or 2-3 years of infertility(25.2%)(P0.05).IUI tended to have a better pregnancy rate per cycle for the couples with male factors(28.1%),cervical problem(28.6%),ovulation problem(25.8%) than those with immune factors(15.6%) or unexplained infertility(17.9%).The couples with two or more infertility factors had a significantly lower pregnancy rate per cycle of 9.8%. HMG induced ovulation improved the pregnancy rate per IUI cycle(37.5% vs.10.8% for natural ovulation).The pregnancy rate per IUI cycle for the women with primary infertility and secondary infertility was 17.2% and 26.3%,respectively.The pregnancy rate per cycle in the women with IUI once a cycle was 17.8%(performed before ovulation) and 26.5%(performed after ovulation).The pregnancy rate per IUI cycle in the couples with grade a+b sperm count(1-5)×106,(5-10)×106,(10-20)×106,and 20×106 was 6.1%,25.0%,25.7% and 25.2%,respectively.Conclusions: Many factors have their effects on the pregnancy rate per IUI cycle,and a comprehensive evaluation should be performed before the procedure to achieve the optimal outcome.