What does Mazras mean? It does not seem to mean the same thing that it means by a man. If it means releasing of the egg which takes place internally, how would a C section be excluded. Also the gemmarah in nida says if a woman
mazras first she will give birth to a boy. What is the metzius?
D. Bennett, Toronto, Canada
Your question was the topic of discussion in our discussion forum a few years ago. Here are the main points of what was written-
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[From Daf-Discuss to Berachos 060:4]
Regarding "Ishah Mazri'a...," the Gemara may be referring to a certain physiological response that occurs at some point during conjugal relations. The Gemara may also be referring to ovulation. Medical experts will explain that being that the gender of the child is determined by the male, since the spermatozoa that carry the y-chromosome are faster than those that carry the x-chromosome, but those that carry the x-chromosome are more durable than those that carry the y-chromosome, if ovulation has occured prior to conjugal relations, the y-chromosome spermatozoa will reach the egg first. If it occurs afterwards, those carrying the y-chromsome will die off, and those carrying the x-chromosome will endure and fertilize the egg. -Y. Shaw
[From Daf-Discuss to Berachos 060:6]
Regarding "Ish Mazri'a Rishon, Yoledes Nekevah," etc. (which seems biologically unintelligible (see Torah Temimah to Parshas Tazria 12:1:5), and see ArtScroll on Nidah, who suggests that a woman also gives forth seed, which does not tally with known facts), I was once shown an article many years ago whereby the Gemara can be remarkably reinterpreted to accord with the most advanced scientific research. That article's thesis could well be what the Gemara means by "Ishah Mazra'as Techilah, Yoledes Zachar." See "How to Choose the Sex of Your Baby," an article by Roger A. Hunt, Copyright 1996 (based on _How to Choose the Sex of Your Baby_, by Dr. Landrum B. Shettles, MD, and David M. Rorvik. Published by Doubleday & Co.; copyright 1984). -J. Pearlman