| Answer | Crossword Clue |
|---|---|
| nidation | implantation of an embryo in the lining of the uterus |
| endometrium | The mucous membrane lining the uterus, which thickens during the menstrual cycle in preparation for possible implantation of an embryo |
| preimplantation | Occurring or existing between the fertilization of an ovum and its implantation in the wall of the uterus |
| conceptuses | The embryo in the uterus, esp. during the early stages of pregnancy |
| menstruation | The process in a woman of discharging blood and other materials from the lining of the uterus at intervals of about one lunar month from puberty until menopause, except during pregnancy |
