A hefsek taharah must be an internal check that reaches inside all the crevices of the vagina. Therefore, wearing white underwear or wiping externally with toilet paper are not acceptable substitutes for a hefsek taharah.

The hefsek taharah must be performed before sunset. If you inserted the cloth by sunset, even if you did not remove it until after sunset, it would be valid. If the cloth was not inserted before sunset, then unfortunately you may not count the next day as day one of your shivah neki'im. Please get back to us if there are extenuating circumstances that would make an earlier immersion critical (such as known fertility concerns, or shalom bayit issues).

While the hefsek taharah should preferably be performed in the late afternoon, we recommend performing an additional bedikah in the morning, so that if you forget later in the afternoon you may rely on it as your hefsek and start counting the shivah neki'im the following day.

Please feel free to get back to us with any further questions.