Final answer:
The Nurse's or women's health study found that the timing of first birth is associated with changes in breast cancer risk. Late timing of first birth increases the short-term risk but decreases the long-term risk of breast cancer.
Step-by-step explanation:
The findings from the Nurse's or women's health study boil down to the fact that the timing of first birth is associated with changes in breast cancer risk. Late timing of first birth is linked to a short-term increase in breast cancer risk, but a long-term decrease in risk. This means that women who have their first child at a later age may have a higher risk of breast cancer in the short term, but a lower risk in the long term.