Yosef Karo, Shulchan Aruch — Yoreh Deah 14 The rule of a fetus in the mother's belly
“ And all this only comes to prove it's permitted by its mother's shechita, like other fetuses found in it. But if that beast then gives birth, also that limb that was emerged and retracted is permitted, as its own shechita permits everything. ”
Yosef Karo, Shulchan Aruch — Yoreh Deah 14 The rule of a fetus in the mother's belly
“ Seif 5 A fetus that stuck out a limb that becomes forbidden, then the mother is shechted and they removed the fetus and behold it's female, its milk is forbidden to drink, since it follows the rule of its body parts and it has one limb forbidden, and behold it's like treif milk mixed with kosher milk.עובר שהוציא אבר ונאסר האבר, ואחר כך נשחטה האם והוציאו העובר, והרי היא נקבה –- החלב שלה אסור לשתותו, הואיל והוא בא מכלל האברים ויש בה אבר אחד אסור, והרי זה כחלב טריפה שנתערב בחלב כשרה. ”
