2,133. What It Means to Follow the Rules of Both a Boy and a Girl
Hilchos Issurei Biah 10:20
When we say that a woman follows the rules that apply after giving birth to a boy and a girl, it means that she is prohibited to her husband for 14 days like one who delivers a girl. The first seven days she is definitely prohibited, so only the last seven days are out of doubt. She doesn’t receive any pure days after day 40 like one who delivers a boy, so if she sees blood between day 40 and day 80, it’s not pure blood. Rather, we treat it as niddah blood, or zivah blood if it comes in her zivah days, as has already been discussed. Similarly, if she sees blood only on day 81, she is considered a niddah out of doubt. She must keep seven niddah days because maybe she miscarried a female and her niddah days don’t start until after her pure days have ended, as has already been explained.
Hilchos Issurei Biah 10:21
When we say that a woman follows the rules that apply after giving birth to a boy and a girl plus those of a niddah, it means that she is prohibited to her husband for 14 days like one who delivers a girl. If she sees blood on day 81, there’s a doubt as to whether or not she’s a niddah. Similarly, if she saw blood on day 74 and on day 81, there’s a doubt as to whether she’s a niddah. Likewise, if she saw blood on day 41, there’s a doubt as to whether she’s a niddah even if she saw blood on day 34. She is prohibited to her husband until day 48, just like one who delivers a boy. Like a niddah, she doesn’t have any pure days. Regarding blood that she sees from the day of her miscarriage until day 80, if it comes in her niddah days, she’s a niddah out of doubt starting seven days after the miscarriage; if it comes in her zivah days, she’s a zavah out of doubt. For all the days after birth, the principle of an expected time for menstrual blood does not apply. Similarly, if she sees blood on day 81, she is still in a quandary and is a niddah out of doubt even if she only saw blood for one day. Once she has re-established a menstrual pattern after 80 days, this doubt will be resolved and she will either definitely be a niddah or definitely be a zavah. Similarly, for seven days from the time of her miscarriage, she is definitely a niddah if she miscarried during her niddah days, as has been discussed.