Women ruling on Halachah

Q: Is it permissible for a woman to give a halachic ruling in matters regarding Family Purity?
A: In order to rule, one must have knowledge of the issues. If she knows, she can rule. This is extremely rare. The word "rule" (lifsok) means to decide in a new matter. But in issues which have been previously ruled upon, a woman can certainly rule, with the condition that she is knowledgeable in that area. And there are, in fact, women who know the Halachah in the area of Family Purity (see Rama, Yoreh Deah 242:14. Pitchei Teshuvah, Choshen Mishpat 7:5).