The Gemara in Masechet Shabbat on Daf 87 discusses some differences between the physical bodies of Jews and the bodies of non-Jews. The Gemara explains that the bodies of non-Jews are different because of the foods they consume. Goyim eat reptiles, insects, frogs, and many other foods that Jews do not eat, and because of this, the bodies of non-Jews are different. One significant difference is the inner temperature of a non Jew. Their bodies as a result of the foods they eat are hotter than that of Jewish people.
Based on this Gemara, the Chatam Sofer (Rabbi Moshe Sofer 1762-1839) extrapolates that it is therefore innately suspicious to consider the findings of a non-religious or non-Jewish doctor valid when diagnosing a Jewish patient. The Chatam Sofer explains that these doctors establish their opinions on their majority constituency who are non Jewish patients. How can their opinions be accurate on Jewish patients if their studies were conducted and ascertained based on non-Jewish patients? So essentiality, the findings of a secular doctor may not be accurate when diagnosing a Jew.
The Chatam Sofer does say however, that this hesitation of following a secular doctor’s prognosis of a Jew does not apply when the case is severe and is a matter of life or death. We follow the rule of ‘Safek Pikuach Nefesh’, which means when it comes to a life or death question, we will take any sound opinion because a life is on the line.
Based on the above, we ask the question about doctors and their diagnoses of women who may shed some blood. The laws of Nidah are greatly affected by a woman’s natural flow. Sometimes however, blood may emanate from a wound which would not affect Nidah. So a lady may need to consult with a physician or qualified authority in order to ascertain the blood’s origin. The question today asks if it would be permissible for a lady to seek out the answer on this question from a secular doctor. Or, do we say that non-religious doctors and/or non Jewish doctors would not be able to give the correct response due to the fact they amassed their knowledge from non-Jewish patients whose bodies are inherently different?
Chacham Ovadia Yoseph writes on this question. He says that there was a time when a lady would only be able to accept the findings of a religious Jewish doctor. But today we hold differently. In today’s technologically advanced culture, we do permit ladies to inquire with secular doctors about blood flow. Today, doctors have the resources to accurately determine the origin of the flow. They have image capturing technologies and other means, which give them the undeniable ability to establish origin.
Halacha Lema'ase, a lady may seek out the diagnosis of any qualified physician when trying to establish if blood flow is from natural causes or from a wound. Qualified doctors use technologies to yield accurate results, and therefore she may use the doctor’s opinion regarding flow of Nidah.