1. When a couple has set a date for the wedding and has started the preparations the bride must make a Hefsek Betahara and count seven clean days. She must do an internal check at least on the first and seventh days. (see the chapter on Hefsek Betahara)
2. Immersion in the Mikveh should be as close to the wedding as possible. During the intervening days after she has immersed in the mikveh and before the wedding she should check herself daily to ensure she is not menstruating. If this was neglected and she checked only once during the seven days before the wedding it is still acceptable.
3. Even if the bride is elderly and has stopped menstruating she must follow these rules since she may have seen blood from the strong emotions associated with getting married.
4. These rules also apply if a divorced couple is getting remarried
5. If a couple was living together and they returned to the ways of the Torah and they decided to get married, even if she is pregnant she must count seven clean days and immerse just like any one else. This is because marriage is a different status from merely living together.
6. If a bride had already prepared for the wedding and has counted seven clean days then a raging argument broke out between the families of the bride and groom causing the wedding to be indefinitely postponed, her seven clean days are also not nullified. When the families calm down and set a new date, the bride must count another seven clean days and immerse in the mikveh again, as it is possible that in her excitement at the setting of the new date could cause her to menstruate.
7. If at the time of the argument a new date has been set and this date is within a month after the argument she need not count another seven clean days.
8. If it was absolutely necessary to have the wedding before she has completed seven clean days, or she unexpectedly became Niddah, the newly married couple may not be alone without a chaperon. Instead the "groom should sleep with other men and the bride with other women" (a single chaperon who is old enough to know what marital relations are is sufficient). It makes no difference if one of them has been previously married.
9. If the couple tried to consummate the marriage but were unsuccessful (if there was not a complete insertion), if she became Niddah before they completed having relations they do not have to separate and can sleep in one room alone like any other married couple.
10. Bleeding caused by the rupturing of the hymen does not make the woman niddah (since only menstruation makes her niddah). If such bleeding occurs when the couple is consummating the marriage or even at a later time while they are newlyweds the couple may continue without worrying that the woman is niddah.
However, even if the woman did not bleed from the first time the couple had sexual intercourse, the woman is considered niddah. Our rabbis feared that the strong emotions associated with having sexual intercourse for the first time might have caused her to menstruate slightly and that the blood was covered by her bleeding from the hymen or by the husband's semen.
11. The only difference between the separations of those who separate because of the blood of virginity and every one else separating from a woman who is niddah: he may lie in her bed if she is not around, likewise she may lie in his bed if he is not around.
12. This separation only applies to those who completed having relations. However, if there was only partial penetration by the husband she might not be niddah. The woman should check to see if she is bleeding: if found clean she is not niddah. They may continue having sexual relations until there is a complete insertion.
13. After they have completed their first relations she is, for the most part like a normal niddah and must do a regular Hefsek Betahara on the fourth day and starts to count her seven clean days on the fifth day (as discussed in the chapter on Hefsek Betahara)
14. As discussed in the chapter on Hefsek Betahara, if she would like to start counting her seven clean days from the next day she may take a hot bath which washes out all of the semen and to wipe herself with a cloth. She may then do her Hefsek Betahara before night time. This is especially applicable if her normal menstruation is soon expected.
15. After she has properly immersed, when the couple resumes having sexual relations, there is no suspicion that she may have seen blood from the strong emotions associated with sexual intercourse. However, if she did bleed from her hymen again they must separate, as in the first time. this applies even if she bled from her hymen several times. As normal she must do a Hefsek Betahara and immerse after seven clean days.
16. If the first relations were complete and after she immersed in a mikveh, they had relations a second time, if she found a stain smaller than the "size of a bean", even if she felt pain from relations she is not niddah since it is assumed that the blood is from another source. If the stain was larger than the "size of a bean" and was found on a colored sheet she is also pure. (see chapter which discusses stains)
17. Strictness should be applied if the stain was found right under her in the spot that they had relations.
18. If they completed having relations the first time after she immersed int he mikveh she need not check if she is bleeding when they again have relations. If she experienced pain the second time it is better to be cautious and check to see if she is indeed bleeding.
19. The couple may have relations for the first time on shabbat, even when there is a possibility that the woman may bleed because of the rupturing of her hymen.
20. When a new husband is unable to complete the first relations because her hymen would not break and a doctor subsequently had to surgically remove it, she does not become niddah since any bleeding she might have had is a result of the operation.
21. Halachically speaking a woman need not check herself for bleeding except when her period is expected at which time all women must check before they resume relations with their husbands. Soon after she gets married a woman who does not have a fixed period must check herself three times before and after having relations. This is to be sure that she does not have uterine bleeding from sexual relations. 14
22. After the woman has finished bleeding due to the rupturing of the hymen, (this might take several times, and even though she is she is considered niddah, she is not considered as one who menstruates due to relations (see the chapter on Bleeding from Relations) since here the blood is from a wound and is not uterine.)
After she has ceased to bleed once, she must check for blood before having relations and both he and she must check after relations, this must be repeated three times and it is supposed to prove that she does not bleed from relations.
23. This checking need not be done after every time they have relations in one night, instead every time they finish they should wipe themselves with a clean, white, checked cloth and in the morning they may check the cloths if blood is found she is impure.
24.If she checked herself and lost the cloth she should not have relations until she checks again.