A study led by the University of Helsinki in Finland has found that giving birth to more than the average number of children or having no children, or delaying birth to birth, may result in a shorter lifespan and faster biological aging. The researchers found this association fits with theories of the "disposable soma" theory, which suggests that if more resources are used for reproduction over survival, there is less left for the latter. Women who had children early in life also showed signs of faster biological ageing and shorter lives, but these differences disappeared after controlling for other factors like alcohol consumption and body mass index (BMI). The researchers suggest that factors such as medical conditions may influence childbearing and health later in life. The study's findings should not be taken as health advice for individuals but as a population-level association.