Warning: these figures indicate the number of cases found in the data file. They cannot be interpreted as summary statistics of the population of interest.
AGEAT1STBIRTH (V212) reports the age of the woman at the time of her first birth. This variable is calculated by using the century month code (CMC) of the date of the woman's first birth (DOB1STKIDCMC) and the CMC of the woman's date of birth (DOBCMC).
Fertility Variables -- TOPICS