There is nothing in the Teachings against leaving our bodies to medical science. The only thing we should stipulate is that we do not wish to be cremated, as it is against our Bahá'í Laws.
As many people make arrangements to leave their bodies to medical science for investigation, he suggests that you inquire, either through some lawyer friend or through some hospital, how you could do this, and then make the necessary provision in your Will, stipulating that you wish your body to be of service to mankind in death, and that, being a Bahá'í, you request that your remains not be cremated and not be taken more than an hour's journey from the place you die. The spirit has no more connection with the body after it departs, but, as the body was once the temple of the spirit, we Bahá'ís are taught that it must be treated with respect.
- Shoghi Effendi (From a letter dated 22 March 1957 written on behalf of Shoghi Effendi to an individual believer; The Compilation of Compilations, vol. I, Baha’i Burial)