From Longman Dictionary of Contemporary Englishchildbearing age/yearschildbearing age/yearsif a woman is of childbearing age or in her childbearing years, she is of an age when it is physically possible for her to have babies → childbearing
Examples from the Corpus
childbearing age/years• Four hundred million women of childbearing age weigh less than 45 kilograms-their malnutrition is passed on to their infants. 