Most jurisprudents and religious authorities do not allow a human body (embryo or born human being) to be dissected. However, some other scholars[1] say in this regard that if a human body is dissected to make medical and scientific discoveries that are needed by society or for treating threatening diseases, it is permissible but one should not, as far as possible, use a Muslim's dead body. As for dissecting an animal's dead body for scientific researches, it is permissible.
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Answers given by religious authorities to the above question are as under:[2]
Grand Ayatollah Khamenei (may Allah grant him long life):
It is permissible to dissect the body of an aborted baby if saving a respectful life, achieving new medical information necessary for the society, or getting more information about certain diseases that threaten life. However, it is advisable, where possible, not to make use of the dead fetus of a Muslim or of one who is ruled as a Muslim. As for dissecting the dead body of an animal, there is no problem in it.
Grand Ayatollah Sistani (may Allah grant him long life):
It is not permissible to use a human body for dissection.
Grand Ayatollah Noori Hamedani (may Allah grant him long life):
If dissection is required for medical education or training and there is no alternate way, there is no problem in carrying out dissection on an animal fetus.
Grand Ayatollah Saafi Gulpaigani (may Allah grant him long life):
It is not permissible to dissect a human corpse but there is no problem in dissecting the dead body of an animal.

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