Single versus Double IUI

Fertility specialists and couples undergoing intrauterine insemination (IUI) must evaluate whether or not double IUI is more advantageous than single IUI.

What is intrauterine insemination?

IUI is a procedure where male sperm is washed and placed directly into the female uterus during ovulation with a goal of increasing the chances of fertilization. IUI may be used in the following diagnoses:

• Male factor infertility
• Unexplained infertility
• Sexual dysfunction
• Endometriosis
• Donor sperm insemination

Understanding single IUI and double IUI

Fertility specialists often perform IUI in conjunction with ovarian hyperstimulation to improve the chances of success. Oral fertility drugs, such as Clomiphene and Letrozole, or injectable gonadotropins are used to stimulate the ovaries.

Typically, IUI is performed once during a monthly cycle. When reproductive endocrinologists perform IUI twice in a menstrual cycle, it is known as double IUI. Studies (and fertility specialists) are mixed on whether or not double IUI produces better results than single IUI.

In a six-trial review involving 1785 women published in the Cochrane Database of Systematic Reviews, 2010, reviewers compared results of single versus double IUI and discovered double IUI resulted in a significantly higher pregnancy rate than that associated with single IUI.

Likewise, an abstract presented at the 2013 Conjoint Meeting of the International Federation of Fertility societies and the American Society for Reproductive Medicine, also found double IUI pregnancy rates were higher than those of single IUI, particularly in couples suffering from male factor infertility.

However, not all studies have produced such promising results. A randomized trial published by Oxford University Press on behalf of the European Society of Human Reproduction and Embryology in 2010, found that when double IUI was performed in 62 cycles that included ovarian hyperstimulation with multi-follicular development resulted in only one additional live birth over single IUI.

The Takeaway

More studies are needed to determine whether double IUI results in more live birth rates than single IUI.

Fertility specialists always weigh the advantages, risks and costs of double IUI when determining whether it is appropriate for a specific couple.

Internal data at URA has shown double IUI to be beneficial ONLY when the total number of motile cells (TNMC) (calculated as volume x count x motility %) after sperm processing is < 3 million motile sperm.