This is for the laywoman or layman to understand the basic workings of the female reproductive system. After bleeding, FSH (Follicle Stimulating Hormone) will prepare 10-20 eggs to mature in each ovary. Each egg is encased in a follicle. These follicles produce estrogen. A woman’s estrogen levels gradually rise until hitting a threshold, then there will be an LH (Luteinizing Hormone) surge. LH is what actually causes the egg to pop out of the follicle and into the fallopian tubes. The follicle that was holding the egg collapses on itself becoming a yellow body called the corpus luteum. The corpus luteum is what releases progesterone for about 14 days although it can range from 12-16 days. Progesterone raises the body temperature creating a warm environment for a potential fetus and it keeps the uterus in tact. I will put a diagram on here visualizing the above mentioned.