Fertility is the ability to conceive a child. The fertility rate is the average number of children born during an individual's lifetime and is quantified demographically. Conversely, infertility is the difficulty or inability to reproduce naturally. In general, infertility is defined as not being able to conceive a child after one year of unprotected sex. Because infertility is widespread, fertility specialists all over the world assist persons and couples who experience difficulties conceiving a baby.

The Total Fertility Rate (TFR) of a population is the average number of children that are born to a woman over her lifetime if:they were to experience the exact current age-specific fertility rates (ASFRs) through their lifetime and they were to live from birth until the end of their reproductive life.