Comparing the effectiveness of infertility treatments by numbers needed to treat (NNT)

To compare the clinical efficiency of different modes of treatment of infertile couples and to estimate the possible benefit of nutraceutical food supplementation (NFS), the numbers needed to treat (NNT) was calculated in 4143 infertile couples based on controlled trials in recent literature and personal data. The NNT expresses the number of individuals who need to be treated to obtain one complementary pregnancy. In female infertility, the NNT of mild or moderate endometriosis was 8.4, and in anti-estrogens treatment of anovulation, it was 5.9. In tamoxifen treatment of idiopathic oligozoospermia, NNT was 3.9, and in antioxidant supplementation, it was 7.8. Treatment of varicocele yielded NNT of 6.3 and 6.8 after 1 year in multi- or single-centre trials, respectively, and NFS lowered the NNT after 3 months to 2.6. Adding NFS to the male partner increased the ongoing pregnancy rate by IVF with NNT of 8.3, and adding NFS to both partners reduced the NNT to 4.0. Although these results were obtained in heterogeneous trials and populations, it is suggested that the NNT should be useful for comparing the effectiveness of different modes of treatment of the infertile couple, and that complementary nutraceutical food supplementation may be beneficial.