Table 2. Prevalence of anencephaly, encephalocele and spina bifida before and after mandatory folic acid fortification of flour, Brazil, 2001–2014.

Type of birth defect	Pre-fortificationa			Post-fortificationb		Prevalence change, %
	No. of cases	Prevalence, cases per 1000 births		No. of cases	Prevalence, cases per 1000 births
Live births
Anencephaly	1035	0.21		2063	0.16	−24.2
Encephalocele	388	0.08		871	0.07	−14.6
Spina bifida	1400	0.28		2832	0.22	−23.1
Stillbirths
Anencephaly	1056	16.22		1322	10.19	−37.2
Encephalocele	39	0.60		95	0.73	22.3
Spina bifida	80	1.23		123	0.95	−22.8
All births
Anencephaly	2091	0.42		3385	0.26	−38.3
Encephalocele	427	0.09		966	0.07	−13.7
Spina bifida	1480	0.30		2955	0.23	−23.8

^a The pre-fortification study period ran from 1 January 2001 to 31 December 2004 – although fortification became mandatory in June 2014. We analysed the data for 4 938 343 live births and 65 121 still births that occurred during this period.

^b The post-fortification study period ran from 1 January 2005 to 31 December 2014. We analysed the data for 12 987 386 live births and 129 737 still births that occurred during this period.