Pregnancy begins when a woman’s egg and a man’s sperm join. This is called conception or fertilization.
The woman’s role in conception
Each month, one of a woman’s ovaries releases a mature egg (ovulation). The egg travels to the fallopian tube. If sperm are present, one of them may join with the egg to form an embryo. The embryo then travels to the uterus. There, it implants in the uterine lining, where it grows to become a baby. If conception doesn’t occur, the egg and the uterine lining are shed during your period (menstruation). A new cycle begins.
The man’s role in conception
Sperm are made in a man’s testicles. Fluid made by the prostate gland combines with sperm to form semen. During a man’s orgasm, semen flows to the urethra and out of the penis (ejaculation). If the semen was ejaculated in or near a woman’s vagina, sperm may travel into the uterus and the fallopian tubes. There, a sperm may join a mature egg to form an embryo. This results in pregnancy.
Online Medical Reviewer: Donna Freeborn PhD CNM FNP
Online Medical Reviewer: Heather M Trevino BSN RNC
Online Medical Reviewer: Howard Goodman MD
Date Last Reviewed: 04/01/2025
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