Matthews TJ, Hamilton BE. Delayed childbearing: more women are having their first child later in life. NCHS Data Brief. 2009;(21):1–8.
OECD. SF2.3: Age of mothers at childbirth and age-specific fertility. OECD Family Database; 2018. Available from:

Matthews TJ, Hamilton BE. Delayed childbearing: more women are having their first child later in life. NCHS Data Brief. 2009;(21):1–8.
OECD. SF2.3: Age of mothers at childbirth and age-specific fertility. OECD Family Database; 2018. Available from: