Homologous intra-uterine insemination has no advantage over timed natural intercourse when used in combination with ovulation induction for the treatment of unexplained infertility

The objective was to evaluate the role of homologous intra-uterineinsemination compared with timed natural intercourse, both combinedwith ovulation induction, in the management of unexplained infertility.A total of 48 couples presenting at a large teaching hospitalinfertility clinic with unexplained infertility of at least3 years duration comprised the main study group, and 36 coupleswith identical entry criteria but under the care of anotherclinician made up a parallel control group. A randomized designof treatment cycles with within-group and between-group controlswas used. Couples in the main study group were treated witheither homologous intra-uterine insemination or timed naturalintercourse in gonadotrophin-releasing hormone analogue down-regulatedcycles, in which ovulation was induced with human menopausalgonadotrophin and human chorionic gonadotrophin. Alternate cycleswere monitored to enable optimum timing of natural intercourseprovided within-group controls. Couples in the control groupunderwent timed homologous intravaginal artificial insemination.Cycle fecundity and pregnancy outcome in treated and controlgroups were monitored. Cycle fecundity of 0.11 in 85 ovulation-inducedcycles was significantly higher than 0.02 in 62 within-groupand 0.01 in 103 between-group control cycles. There was no differencein conception rates between homologous intra-uterine inseminationand timed natural intercourse cycles with ovulation induction.Of the 11 established pregnancies in the ovulation induced group,nine delivered healthy babies (five singleton, three twin, onetriplet) and two were ectopic. Results confirmed the value ofactive management for couples with long-standing unexplainedinfertility but failed to demonstrate any advantage of homologousintra-uterine insemination over ovulation induction alone.