Pregnancy can happen when a sperm cell and an egg cell meet inside the reproductive system of a female body. This can happen when two or more people engage in penis-vagina sex when no birth control is used, or is used incorrectly. This can also happen through a process called insemination, a planned medical process in which a doctor or health care provider introduces sperm cells to join an egg cell and create a pregnancy (but where no penis-vagina contact occurs).
Egg cells are stored in the ovaries of the female reproductive system. About once per month, hormones in the body will cause the lining of the uterus to thicken, and an ovary will release a mature egg cell into a fallopian tube. This process is called ovulation. The fertilized egg cell will slowly travel through the fallopian tube towards the uterus.
Sperm cells are produced in the testicles of the male body. When the male becomes sexually excited, semen comes out of the penis during ejaculation. If semen gets near or into another person’s vagina, sperm cells will swim up the cervix and uterus into the fallopian tubes, on a mission to join an egg cell.
If a sperm cell joins an egg cell (a process called fertilization), the fertilized egg continues down the fallopian tube towards the uterus. The fertilized egg cell may attach itself to the lining of the uterus (a process called implantation), and pregnancy begins.
A pregnancy may be planned, or may occur unintentionally. Click here for pregnancy options, including abortion, adoption, and parenting. No pregnant person should be forced or pressured into any of these decisions.