
Your baby today
To embed itself in the lining of the uterus, the embryo-to-be needs the help of progesterone, secreted after ovulation by the empty egg follicle, the corpus luteum (shown in pink in this cross section of an ovary). Progesterone helps the lining thicken.
Do you feel different? You'll find yourself analyzing every twinge in your body as you look for signs that you're pregnant.