Acceptable pregnancy rate of unstimulated intrauterine insemination: a retrospective analysis of 17,830 cycles.

PURPOSE: To evaluate the pregnancy rate (PR) of unstimulated intrauterine insemination (IUI). METHODS: This was a retrospective study in a private fertility clinic. Between 2004 and 2013, a total of 4,045 women underwent 17,830 cycles of unstimulated IUI. The etiologies of subfertility in the couples were unexplained (51 %), male factor (36 %), coital problems (9.5 %), and cervical factor (3.5 %). RESULTS: The PRs/cycle, between the 1st and 9th trials, in women <35, 35-37, 38-40, 41-42, and >42 years of age were 8.2, 7.3, 5.5, 3.6, and 0.9 %, respectively. In 10,076 cycles in which the male partner had a total motile sperm count ≥5 million, the PRs in the respective age groups were 9.9, 8.6, 6.1, 4.8, and 1.2 %. The largest-sized reported PRs for clomiphene citrate (CC)/IUI in the respective age groups were 11.5, 9.2, 7.3 4.3, and 1.0 % (4,199 cycles in total, Dovey et al., FertilSteril, 2008;90:2281-2286). There were no significant differences in PRs between unstimulated IUI and CC/IUI. CONCLUSION: PR for unstimulated IUI was similar to the reported PR for CC/IUI. Although this was a retrospective study without a control group, to reduce multiple pregnancy rate, we believe that unstimulated IUI is a reasonable treatment.

Bibliometric study of radiation application on microdose useful for new drug development.

In spite of the sharp increase in both private and government R&D fund, the number of newly approved medicines for market had decreased since the 1990s. This is attributed to a large extent to the bottleneck in the critical path arising from the great disparity between animal model in pre-clinical trial and human model in clinical trial. This bottleneck may be expected to be gotten rid of by change in paradigm of drug development based on microdosing, which is enabled by radiation-related imaging technology. However, this is impossible without being accompanied by interdisciplinary joint researches, in which clinical investigators belonging to medical schools or hospitals play the most decisive role. In this article, authors verify based on bibliometrics that Japan has not employed the opportunity for revitalizing drug research activities because Japanese researchers' attitude toward radiation technology may not be so positive in comparison with the US, and because the role which clinical investigators play in the phase of pre-clinical trial is smaller in Japan than in the US.