Xa i-ovum sele ichunyiswe nge-sperm sendoda, kuphuma i-zygote, ethi ikhule ibe sesinye isidalwa. I-ovum ichunyiswa ingaphakathi emzimbeni womntu ongumfazi, kutsho kuvele i-embryo ethi ikhulele ngaphakathi kweuterus, isondliwa yi-placenta kamama.