Exposing female mice to chemicals found in cigarette smoke before pregnancy or during the period in which they nurse their young impairs the reproductive capacity of their female offspring, a new study finds.
Many women stop smoking when they discover they are pregnant, aware that this habit endangers the baby. The new data suggest that may not be enough to protect their daughters' long-term reproductive health.
In mammals, females develop their lifetime supply of eggs—housed in the ovaries—while still in the womb or shortly thereafter. At menarche, women gradually begin to lose this dowry through monthly ovulation until their eggs run out at menopause.
However, data had suggested other factors, including cigarettes, can cut into egg reserves. For instance, women who smoke tend to reach menopause sooner than nonsmokers.
To test whether this risk is passed along to offspring, scientists injected female mice with two chemicals found in cigarette sm