"And eat it with matzah and bitter herbs"Numbers 9:11.

[Those who must offer the "Second Passover," as explained in Positive Commandment 57, are] commanded to eat the Second Passover Offering on the eve of the fifteenth of Iyar, together with matzah and bitter herbs.

Women are exempt from this mitzvah (just as they are exempt from offering the Second Passover Offering).