The miracle of birth is one of the most awe-inspiring experiences of life. As the person which was inside the woman begins his life on the outside, the couple must abstain from sexual relations for a short time.
1. According to the law as described in the Torah itself, the woman is considered niddah after childbirth for seven days for a boy and for fourteen days for the birth of a girl. The torah law is that any bleeding which occurs for 33 days following the seven (for a boy) and for 66 days following the fourteen (for a girl) does not render the woman niddah. In fact the couple need not abstain from physical intimacy or even sexual intercourse while she is discharging this blood.
2. As was stated, the above represents the law as it was written in the torah, however, the great Geonic rabbis decided that since the violation of the laws of niddah is so grave, it is important that the couple not get used to having physical intimacy while she is bleeding. They therefore determined that any blood from the uterus, even the discharge occurring for 33 or 66 days following birth, renders the woman niddah. Moreover, according to the rabbis the woman must wait for seven clean days after she stops seeing blood before going to the miqveh and resuming physical intimacy with her husband. This rule applies even if she has already immersed. Transgression of this rule is grave.
3. Today all woman who give birth are accustomed to follow all of the regular laws of niddah: that she must count seven clean days and that the couple must abstain from physical contact if she is still bleeding as in the regular rule of the niddah (zabah gedola) from the Torah. 205.
4. If a woman gave birth to a girl she may not immerse before fourteen days have passed even if she has already finished counting seven clean days. If she immersed before fourteen days have passed she remains impure until the fifteenth night at which time she may immerse.
5. All of the regular rules of niddah and the behavior which might lead to physical contact (chapter VII) apply also for one who has given birth. 207.
6. If a woman has already properly immersed during the forty days after the birth of a boy or eighty days after a girl. If she subsequently bleeds and has become "niddah" before the end of this time when she immerses she must not make a blessing on her immersion. This is because her "niddah" status is not actual but dictated by the Geonic rabbis.
7. A woman who recently gave birth and saw a stain the same strictness as is normally followed is observed by her. However, in slightly questionable cases one may be lenient. It is best to consult your rabbi in such cases.
8. Certain women are accustomed not to immerse for forty days after the birth of a boy and eighty days after the birth of a girl. This custom is a mistake and was learned from people who do not believe in the Oral Tradition. Any woman who has in the past been following this custom should instead count seven clean days then immerse like everyone else.
9. If a woman who has completed forty days of pregnancy miscarries, she is considered niddah as if she had given birth to a girl and must not dip until the fourteenth day has passed and has counted seven clean days. The seven clean days may be included in the fourteen days.
10. If a woman has not completed forty days of pregnancy (including the fortieth day) miscarries she is not "niddah" as if she gave birth. (11.) However she is considered a niddah even if she did not bleed and must count seven clean days then properly immerse.
11. Additional situations of miscarriages which might occur (for example, if she only miscarried a placenta) or any other questions should be asked of your rabbi.
12. There is a rule cited in the Gemara, that the uterus does not open without bleeding: This refers to a uterus which opened by itself. However, an internal examination done by a doctor with a utensil or his fingers very possibly might not lead to bleeding. Therefore if after a medical examination she checked herself and found herself clean, she is not niddah. This rule also applies to a woman in the middle of her seven clean days so that she may continue counting.
13. Because of this rule (that the uterus does not open without bleeding) if a baby stuck his smallest limb out and then returned it, even if the woman did not then give birth she is niddah for 14 days.
14. When a woman gave birth through a Caesarian she does not have the rules of a woman who gave birth vaginally (seven days for a boy and fourteen for a girl; or the rules of pure blood discussed above). She does have the rules as regular niddah and if she did not bleed from her uterus through the vagina she is not considered niddah at all.
15. The breaking of a woman's water is not considered bleeding to render a woman niddah unless blood is seen with the water.