Vitamin D association with estradiol and progesterone in young women.
Knight JA, Wong J, Blackmore KM, Raboud JM, Vieth R.
Cancer Causes Control. 2009 Nov 15. [Epub ahead of print]
PMID: 19916051
Conclusions Higher levels of vitamin D may reduce progesterone and estradiol, providing a potential mechanism for reduction in breast cancer risk from increased vitamin D exposure in young women