Negative Commandment #132
Sefer Ha’mitzvos Ha’Katzar (The concise book of mitzvos)
By the Chofetz Chaim
This book lists the Torah mitzvos that can be observed today
Second Section – the Negative Commandments
132. It is a negative commandment "do not have relations with a ritually impure woman"
as it states in Vayikra (Leviticus) 18:19, "do not approach a woman who is a niddah (ritually impure)." A man who has relations with a woman who is a niddah, even if she was completed her days of being a niddah but has not yet gone to a mikvah (ritual bath) with 40 seah of water, both of them are spiritually excommunicated and the child born from this relation has a defective status (which our Sages state it is proper to stay away from him.)
It is forbidden to have relations with one's wife close to the vestes (which is when her menses is expected to begin). How long is considered her vestes? If it is usually seen during the day, it is forbidden from the beginning of that day. If it is normally seen at night, it is forbidden from the beginning of that night.
A woman who has given birth is considered like a niddah to her husband, even if no blood was seen during the childbirth. This is true if the child lived or passed away. In our lands, after 7 days for a baby boy and 14 days for a baby girl, if she is clean from blood, she may inspect herself for purity and begin counting her seven clean days. Afterwards, she may go to the mikvah and then she is permitted to her husband. If she sees blood after going to the mikvah, she is forbidden to her husband like all other women (because she does not fulfill the days of her purity as stated in the Torah). If a man has relations with a woman after she gave childbirth but before she went to the mikvah, it is the same as having relations with a niddah.
TO BE CONTINUED