If a Kallah became a Nida right after her wedding, prior to having marital relations, must she wait five days?
Did not yet have Yichud with her Chasan: A Kallah who became a Nida after her wedding but prior to even having Yichud with her Chasan is not required to wait five days prior to beginning her Hefsek Taharaha, and rather as soon as the bleeding ends she can perform the Hefsek Taharah and begin her Shiva Nekiyim.
Had Yichud with her Chasan: A Kallah who became a Nida after her wedding and after having Yichud with her Chasan, but prior to even having marital relations with her Chasan some Poskim rule that she is required to wait five days prior to beginning her Hefsek Taharaha. Other Poskim however rule that even in such a case she can perform the Hefsek Taharah and begin her Shiva Nekiyim as soon as the bleeding ends and is not required to wait five days. This applies even if the Chasan and Kallah were already affectionate, so long as they did not yet have marital relations. Practically, one is to contact a Rav regarding if she may be lenient in such a case.
 See Shiureiy Shevet Halevi 196 p. 298
 Taz 196/7
 The reason: As she does not contain any Zera of her husband and hence the entire reason for waiting five days is irrelevant. It is not logical to say that we decree even in this case due to a case in which marital relations already took place. [Taz ibid]
 Implication of Taz ibid that explicitly conditions the case to be prior to Yichud as only then does she “not come even close to any resemblance of marital relations”; Regarding this law by a wife who saw her period after Mikveh but prior to Tashmish some Poskim rule she must wait five days in all cases [Nodah Beyehuda Tinyana 125, brought in Pischeiy Teshuvah 196/12] or at the very least if she already came home and had Yichud. [Sidrei Taharah 196/39 in name of Soles Belula] See Shiureiy Shevet Halevi ibid
 Meil Tzedaka 196/32 and so rule regarding even a regular wife who became a Nida after Mikve: Sidrei Taharah 196/39; Pnei Yehoshua 12; Teshuvah Meahava 3; Imrei Yosher 2/92; Piskei Dinim 196/29; Aruch Hashulchan 196/39; Ben Ish Chaiy Tzav 2/16; [Some of these Poskom do not explicitly discuss the case if she already arrived home, although it seems from their lack of discussion that they are lenient so long as it is prior to Tashmish]
 Meil Tzedaka ibid; Shiureiy Shevet Halevi ibid
 Shiureiy Shevet Halevi ibid concludes that in a case that affectionate touch occurred one is to ask a Rav; Taharah Kehalacha 15/6 regarding a wife after Tevila is completely lenient and so is implied from majority of Poskim