And following the third trimester, we have the process of birth, also known as parturition. So let's begin by discussing what takes place within the first trimester. So let's suppose that sexual intercourse did not yet take place and the menstrual cycle of that woman begins. Now, following sexual intercourse the sperm is deposited into the vaginal tract. It then travels into the uterus and it travels up into the fallopian tube. And eventually, it reaches and combines with the egg cell.