Good Preconception Vitamin D = more live births
A total of 1191 women had evaluable preconception 25[OH]D levels, and of these, 47% had adequate concentrations, defined as 75 nmol/L or more. They first observed that higher vitamin D concentrations prior to conception were associated with an increased likelihood of any pregnancy.
Similarly, women with adequate preconception vitamin D concentrations were more likely to achieve a live birth, compared to women with insufficient vitamin D concentrations.