Harvest of uterus and embryos from pregnant mice. (A-D) Removal of uterus from female. (A,B) Location and direction of cuts for opening the abdominal cavity (arrows). (Black arrows) The uterine horn; (AC) abdominal cavity. (C, yellow dashed line) Cuts to remove the uterine horn. (C') Higher magnification of the uterine horn; (yellow arrow) the location of the mesometrium. (D) Isolated uterine horn. Cut between each sac (blue arrow) to separate individual embryos. (E) Individual embryo (E) with placenta (P) in uterus; (white arrow) location where forceps are inserted to remove embryo. (F) Removal of embryo from the uterus. Forceps are used to tear muscle along the black dotted arrow to release the embryo; (orange arrows) the location of the head.