1. Rav Papa explains why a woman who sees Dam when pregnant is deemed Teme'ah only from that point onward, and not retroactively.
2. A pregnant woman does not need to examine herself at the time she normally would expect to see Dam.
3. The Tana'im disagree about why a nursing woman does not normally experience her period.
4. The Gemara explains the difference between the two opinions (see #3).
5. There is a dispute about when a woman is called "almost old," at which time she no longer normally sees Dam.
A BIT MORE
1. Since her limbs and head are heavy, she is presumed to have no menstrual blood. Accordingly, we do not suspect that she had a flow of Dam earlier than when she notices the Dam.
2. The Gemara states that this is true even if we maintain that a woman who does not examine herself when the time of her period normally arrives is deemed Teme'ah by Torah law.
3. Rebbi Meir: The blood turns into milk for nursing. Rebbi Yosi, Rebbi Yehudah, Rebbi Shimon: Her limbs do not recover fully from the birth until 24 months later, causing her to miss her periods.
4. According to Rebbi Meir, the woman has no Dam for as long as she is nursing her child, even if she nurses for five years. According to Rebbi Yosi and the other Tana'im, she is assumed to have no Dam only for 24 months, regardless of whether she is actually nursing.
5. Rav Yehudah: If her friends call her an old lady, she is deemed old. Rebbi Shimon ben Lakish: If they call her "Ima" and she is not embarrassed, she is deemed old.