Leviticus 15:19-23

A woman was considered ceremonially unclean during menstruation

See also

Leviticus 12:1-5; 15:25-30
Isaiah 30:22
Leviticus 18:19

Sexual intercourse during menstruation forbidden

See also

Leviticus 20:18
Ezekiel 18:5-6; 22:10
Genesis 31:35

The discomfort of menstruation

See also

6236 sexual sin
7424 ritual law
7426 ritual washing