Half the devout Catholics defied Church teachings .
Half the devout Catholics used contraception to postpone births -- the number of births nationwide fell from 250,000 in 1930 to about 228,000 and did not recover until 1940 .
Half the devout Catholics defied Church teachings and used contraception to postpone births -- the number of births nationwide fell from 250,000 in 1930 to about 228,000 and did not recover until 1940 .