Child birth

‎The uncleanness produced by a male child lasted “seven days,” and that by a female child “two weeks.”—(Lev. 12:2, 5.) The reason for a female child producing greater uncleanness than a male one is, probably, to be found in the fact that woman was the first in the transgression in Eden. Whatever be the reason, however, here is the fact, that the uncleanness was greater in the case of one sex than the other; and this fact shows that it was the child which was the cause of the uncleanness. Now only unclean things could produce uncleanness. Hence all Jewish children were unclean by birth; and as a consequence, all Jewish mothers were rendered unclean by their offspring. Mary and her son were no exceptions to this rule; for it is recorded that, “When eight days were accomplished for the circumcising of the child, his name was called Jesus, which was so named of the angel before he was conceived in the womb. And when the days of her purification, according to the law of Moses, were accomplished, they brought him to Jerusalem to present him to the Lord.”—(Luke 2:21, 22.)
. Vol. 11: The Christadelphian p 14–15

Male, represents the bridegroom, Christ. He had sinful nature, but not sin, therefore unclean 33 days. Female, represents bride, ....we have both sinful nature and sin, therefore doubly unclean, therefore 66 days.