This technique is used for the conception of a human embryo(胚)outside the mother's body. Several ova(卵子), or eggs, are removed from the mother's body and placed in special laboratory culture dishes; sperm from the father are then added. If fertilization(受精)occurs, the fertilized ovum, after undergoing several cell divisions, is either transferred to the mother's or a surrogate mother's(代理母の)body for normal development in the uterus(子宮), or frozen for later implantation(移植).