A woman may immerse in the mikveh as soon as fourteen days have passed, as stipulated in the Torah (VaYikra 12:5, "If she gives birth to a female, she shall be
temeiah for two weeks similar to her status during
niddah"). In theory, a
hefsek taharah may be made as early as the
fifth day (where the day of childbirth is day one), followed by
seven clean days and waiting an extra two nights before immersion. In practice, however, it is very rare for
postpartum bleeding to stop soon enough for immersion to be possible after two weeks, and a woman typically makes a
hefsek taharah when bleeding stops, with no unique delay after giving birth to a girl.
Some communities developed the custom of delaying immersion after having a girl until the end of eighty days (the time the Torah establishes as
dam tohar, a distinct law that has lost is practical significance). Many halachic authorities have condemned any such stringency, and today it is not practiced.