If my wife had seven days without her period, and she went to the mikva without checking with a white cloth, because she has a very rare period due to medication she takes, and didn’t think it would be necessary to do the checks, is she required to begin another seven days of checking?
Every woman must make a “hefsek tahara” in order to become permitted to her husband. If she didn’t make any bedikos she has to go through the process now. Meaning, she should make a hefsek tahara, count seven days and make bedikos, and then go to the mikvah again.
Y:D 196-1, Sidrei Tahara 196-23, Shut R’ Akiva Eiger 60.