All perfect praise be to Allah, The Lord of The Worlds, and may His peace and blessings be upon our Prophet Muhammad and upon all of his family and companions.
There is no harm on using the placenta of animal’s embryo that is lawful to eat such as: goat and horse for cosmetic and medical purposes and other lawful uses so long as his mother was slaughtered in the due form, since placenta is part of an animal that is lawful to be eaten. Thus eating and using its parts is permissible provided that it doesn’t contain blood.
Furthermore, using placenta of animal’s embryo is permissible so long as it was taken from an animal during his lifetime according to Malikiee’s doctrine as stated by Al-Sheikh Al-Hatab Al-Maliki (May Allah have mercy on his soul): ”As the Amniotic sac. is part of the placenta which protects the embryo, Ibn Rushed is of the view that animal’s placenta is pure (Lawful)as is the case with eating a camel slaughtered in the due form.” [Mawaheb Al-Jaleel vol.1 pp.289].
In addition, Al-Imam Ad-Dsoqi (May Allah have mercy on his soul) stated:” There are three opinions as regards eating the placenta of animal’s embryo; the third one is: eating the placenta is to be measured according to the permissibility of eating the animal itself whether it is lawful or unlawful to be eaten; if eating the embryo was lawful then eating its placenta is lawful but if it was unlawful then eating it is impermissible.” [Hashyat Ad-Dsoqi vol.6 pp.327].
On one hand, if the placenta was from a pure or lawful animal then using it for trade, manufacturing or medical purposes (for external or internal uses) is permissible.
On the other hand, if it was taken from an animal that wasn’t slaughtered in the due form or from one which is unlawful to be eaten, then it is considered an impure dead part, for the Prophet (PBUH) said (What means): ” Whatever is cut off of an animal when it is alive is dead.” [Related by Al-Imam Ahmad] Besides, Al-Sheikh Al-Ansary stated:” The placenta of an animal takes the same ruling of the animal itself whether it is pure or impure .i.e. the hand of human is pure and the hand of the cow is impure.” [Asnaa Al-Mataleb vol.1 pp.11].
However, using the placenta of impure animal in manufacturing cosmetic and medical products for necessity is permissible stipulated that no substitute was available, since Al-Sharwani (May Allah have mercy on his soul) stated: "Using parts of impure animals for healing is permissible so long as no other pure substitute was available.” [Hawashi Al-Sharwani Al’a Al-Tohfa vol.1 pp.296]. The aforementioned permissibility implies on both: external and internal usage.
In conclusion, the evidence on the permissibility of using impure substances or parts of animal for necessity is the following narration whereas: “Allah's Messenger (PBUH) commanded them to the milch she-camels and commanded them to drink their urine and their milk.” [Agreed upon]. Further Al-Imam Ashafiee (May Allah have mercy on his soul) stated:” Based on necessity, a person is permitted to eat from a dead animal if no substitute was available since the necessity knows no law.” [Al-Sunnun Al-Kobra vol.2 pp.579] for Al-Byhaqi. And Allah knows best.