Study question

Is ejaculatory abstinence before IUI essential factor for pregnancy?

Summary answer

The period of ejaculatory abstinence before IUI is not related with pregnancy rates

What is known already

The total number of motile sperm inseminated has been cited as the most predictive index of conception in IUI cycles. Intercourse on the day of hCG administration might cause concern about a lower recovery of total motile sperm. However, optimal period of ejaculatory abstinence before IUI is not yet established.

Study design, size, duration

Retrospective analysis of 804 IUI cycles performed between April and December in 2015. The period of ejaculatory abstinence before IUI, semen analysis parameters of the ejaculate (pre-wash) and the insemination specimen (post-wash) for IUI, and pregnancy rate following ovulation induction and IUI were recorded.

Participants/materials, setting, methods

The whole ejaculate was prepared for insemination using a technique of density gradient separation with centrifugation. Ejaculatory period before IUI was divided into 3groups (0-2 days, 3-5days, >5 days).

Main results and the role of chance

In each group, age, semen volume, sperm motility (pre-wash) and liquefaction time did not show significant differences. Although the longer EA period, the more total motile sperm count (pre-wash) was observed (88.2, 137.2, 194.7(*106/ml), p<0.05), but there were no significant differences in post-wash total motile sperm count (8.3, 10.9, 11.7 (*106/ml), p>0.05). Total pregnancy rate was 19.4% (144/804). There were no significant differences among three groups in the pregnancy rate (22.5% (14/80), 18.7% (53/310), 19.3% (77/414); p>0.05).

Limitations, reasons for caution

To identify the period of EA, we asked for questionnaire survey to patients. So, there could be recall bias. Prospective randomized studies with larger sample size will be required to confirm our conclusions.

Wider implications of the findings

There were few studies about relation between pregnancy rate and period of EA before IUI. Our result shows that period of EA before IUI does not affect pregnancy rate. Therefore, we can advise that abstinence before IUI and the interval of intercourse seldom affect pregnancy outcome.