What is not so well known is that as far back as 1972 the issue of metzizah b’peh was discussed by HaRav Moshe Pirutinsky in his “Sefer HaBris.” This monumental work includes Haskamos (approbations) from R’ Chaim Shmulevitz, R’ Yitzchak Hutner, R’ Yitzchok HaLevi Ruderman, R’ Mendel Zaks, R’ Modechai Gifter, R’ Shneur Kotler, R’ Nachum Perlow (Rabbi Yaakov Perlow’s father) and R’ Moshe Feinstein.
On pages 215-216 in his chapter on metzitza, Rabbi Pirutinsky discusses the issue at length quoting many sources – both pro and con. But he concludes that if medical experts (the only ones qualified to do so) determine that there is a danger posed by a mohel using the mouth for suctioning the circumcision wound – it should be performed by other legitimate methods. Ultimately Hazal required metzitza for health reasons. If using the mouth is unhealthy for the child it ought not to be done that way.
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