Vitamin D is an emerging regulator of uterine leiomyoma development. Cohort and interventional studies are pressingly needed to confirm a causal relationship and to investigate the potential therapeutic benefits of vitamin D supplementation.

Research on the effect of adenomyosis on the rate of success of IVF is controversial. Differences in study design, study power, criteria and instrument used to diagnose adenomyosis and choice of controls may explain these discrepancies. To establish whether embryo implantation is impaired in women with adenomyosis, women scheduled for IVF were prospectively evaluated for the presence of adenomyosis and whether this condition affected embryo implantation. Forty-nine women with adenomyosis diagnosed at transvaginal ultrasound with no abnormal uterine bleeding were recruited. They were matched for study period, age, day of embryo transfer and number of transferred embryos to 49 controls without the disease. In women with adenomyosis, 24 out of 76 embryos transferred implanted (32%); this occurred in 16 out of 76 (21%) in unaffected controls. The crude odds ratio of implantation in affected women was 1.73 (95% CI 0.83 to 3.60). The odds ratio adjusted for body mass index (the unique variable found to differ at univariate analysis) was 1.78 (95% CI 0.85 to 3.77). In conclusion, implantation rate is not impaired in asymptomatic women who are diagnosed with adenomyosis at transvaginal sonography. Affected women can be reassured about the effect of this condition on their chances of success.