Until Age of Marriage Act 1929 raised age to 16yrs for both males & females , girls above 12 yrs could be legally married
although it was rare. In earlier times many 'teenage' females would not be of childbearing age. Puberty is related to level of nourishment.As this improves the age of puberty drops.[ There are now in England well over a thousand live births each year to females aged 13 yrs and under]