Niddah

It was taught: R. Simeon b. Gamaliel stated, Among towns-women the lower mark appears earlier because they are in the habit of taking baths; among village women the upper mark appears earlier because they grind with millstones.  R. Simeon b. Eleazar stated: Among the daughters of the rich the right hand side develops earlier because it rubs against their scarves;  among the daughters of the poor the left side develops earlier because they carry  jars of water on them. And if you prefer I might say, Because they carry their brothers on their sides. Our Rabbis taught: The left side develops earlier than the right side. R. Hanina the son of the brother of R. Joshua stated: The left side never developed earlier than the right side except in the case of one woman who lived in our neighbourhood whose left side developed earlier than the right one which later regained its normal strength. Our Rabbis taught: All girls to be examined must be examined by women. So also R. Eliezer entrusted the examination to his wife, and R. Ishmael entrusted it to his mother. R. Judah ruled: Before the period  and after the period,  women examine them.  During the period  no woman may examine them, since in doubtful cases  no woman is allowed to marry  on the evidence of women. R. Simeon ruled, Even during the period  women examine them. And a woman may be relied upon when by her evidence the law is restricted but not when it is relaxed thereby. How so? [She may be relied upon when she states: 'The girl] is of age', so that the latter should thereby be denied the right of mi'un, or 'She is a minor', so that she should thereby be denied the right of performing halizah; but she is not trusted when asserting, 'She is a minor', so that she should have the right of exercising mi'un, or 'She is of age', so that she should be entitled to perform halizah. The Master said, 'R. Judah ruled: Before the period and after the period women examine them'. One can well concede that before the period an examination is required, for should [the same hairs]  be found after the period they would be regarded as a mole;  but what need could there be for an examination after the period seeing that Raba has laid down that a minor who has attained the age of her majority need not be examined since there is presumption that she had by that time produced the marks of puberty? — When Raba stated, 'there is presumption', he meant it in respect of mi'un,  but as regards halizah  an examination is still required.  'During the period no women may examine them', because he is of the opinion [that the presence of hairs] during the period [is a mark of majority] as after the period;  but after the period, when Raba's presumption is applicable, we rely upon women who may, therefore, conduct the examination,  while during the period, when Raba's presumption is not applicable, we cannot rely upon women, and women, therefore, may not conduct the examination. 'R. Simeon ruled, Even during the period women examine them', for he is of the opinion [that the presence of hairs] during the period [is no more a mark of puberty] than it is before the period; and an examination is, therefore, required so that if [the same hairs]  should be found after the period they would be regarded as a mole.  'And a woman may be relied upon when by her evidence the law is restricted but not when it is relaxed thereby.' Who taught this? — If you wish I might say: R. Judah, and [the reference is to evidence] during the period.