Randomized Trial Reports Similar Live Birth Rates with Single and Double IUI

Follicular rupture may usually occur between 22 to 47 hours following hCG administration in patients undergoing IUI. Due to this wide interval, the underlying principle for double IUI is the creation of a longer fertilization period. A recent single-centered randomized trial reiterated that there is no statistically significant difference in the rates of live births between single and double IUI in ovarian hyperstimulation cycles with multi-follicular development. Claimed to be the first randomized trial comparing single versus double IUI, the study findings have been published in the journal, Human Reproduction.
Tayfun Bagis and colleagues from the Baskent University Faculty of Medicine, Turkey, conducted the study on 228 patients to investigate the effectiveness of single and double IUI in multi-follicular OH cycles. Multi-follicular development is described as the formation of a minimum 2 dominant follicles that are of atleast ≥15 mm in diameter, out of which one should be ≥17 mm. The trial included cycles which had the development of multiple follicles without the occurrence of premature luteinization, i.e., >1 ng/mL of progesterone on the day of hCG administration. It excluded those OH cycles which had >5 dominant follicles of more than 15 mm. The selected subjects were randomized to undergo single (group 1=112) or double IUI (group 2=114). IUI was performed on group 1 patients 36 hours following the hCG administration, while in group 2, the first and second IUI was done 18 and 40 hours post hCG, respectively.

The overall live birth rates noted in the single and double IUI were 10.7% and 12.3%, respectively. The researchers did not observe any statistically substantial variation in the live birth rates between single and double IUI (OR=1.16; P=0.835; 95% CI=0.51-2.64). The live birth rates in the two infertility groups are mentioned below.

Infertility groups
Single IUI (%)
Double IUI (%)

Unexplained infertility
11.1
18.4

Mild male factor infertility
10.4
7.7



Although a few earlier studies have reported contradictory findings on clinical pregnancy or live birth rates with single and double IUI, in a recent systemic review and meta-analysis, Polyzos et al (Fertility and Sterility, 2009) demonstrated the absence of any benefit of double IUI over single IUI with respect to clinical pregnancy rates in unexplained infertility. However, a Cochrane review (Cochrane Database of Systemic Reviews, 2003) found that double IUI significantly improves the pregnancy rates when compared to single insemination in subfertile couples, but there was insufficient information pertaining to live birth or ongoing pregnancy rates.

The National Guideline Clearinghouse, in 2004, had recommended the use of single over double IUI whenever patients opt for insemination. More recently, Abdelkader and Yeh (Obstetrics and Gynecology International, 2009) reviewed the potential of IUI as a basic treatment strategy for infertility, and noted the lack of evidence to support the use of double over single IUI. They proposed that single IUI would help in achieving similar pregnancy outcomes and is less expensive than double insemination.

From IVF News.Direct