The Pregnancy Outcomes Comparison on Natural or Controlled Ovarian Stimulation Cycles in Intrauterine Insemination Treatment: An Analysis of 8,893 Cycles View PDF

Intrauterine insemination (IUI) is considered the oldest first-line procedure in assisted reproductive techniques due to its simplicity, easy management and low cost. Moreover, the acceptable pregnancy rates and relatively lower incidence of complications lead most clinicians to direct patients to IUI in routine infertility management plans. Intrauterine insemination involves timed insemination of spermatozoa into the uterus in natural cycles or insemination following stimulation of the ovaries. Although the fact that controlled ovarian stimulation (COS) is routinely used in many infertility centers, there was no clear evidence for a superior effect of ovarian stimulation combination with IUI compared to nature cycles (NC).