Long Term Maintenance of Neural Tube Defects Prevention in a High Prevalence State

Abstract

Objective To assess the efficacy of folic acid (FA) supplementation and fortification in preventing neural tube defects (NTDs) in a high prevalence region of the US. Study design Active and passive surveillance methods were used to identify all fetuses/infants affected by an NTD in South Carolina. Prevalence rates were compared with FA intake to determine the effects of increased intake on NTD occurrence and recurrence. Results From 1992–2009, 916 NTD cases occurred in South Carolina with isolated defects comprising 79% of cases. The NTD rate decreased 58% during this period. There was one NTD-affected pregnancy among 418 subsequent pregnancies (0.2%) in mothers with previous NTD-affected pregnancies who consumed periconceptional FA supplements and four NTDs among 66 pregnancies (6.1%) in which the mother did not take FA supplements. Folic acid supplementation increased from 8% to 35% from 1992–2007 and knowledge of the protective benefits of FA increased from 8% to 65% in women of childbearing age. Conclusions Increased periconceptional intake of FA appeared to reduce NTDs in a high prevalence region. The rate of spina bifida and anencephaly in South Carolina is now essentially the same (0.69 cases per 1000 live births and fetal deaths) as the 1998–2005 US rate (0.69).

Impact of folic acid fortification of flour on neural tube defects: a systematic review

“…The smallest decrease occurred in the state of California in the USA (15?5 %) (23) . Twenty-one articles reported on the prevalence of spina bifida before and after flour fortification (15,16,19,(21)(22)(23)25,26,28,(30)(31)(32)(33)(34)(35)(36)(37)(38)(39)(40)(41) . The largest reductions reported were in Costa Rica (61 %) (28) , Canada (55 %) (21) and Chile (55 %) (25) The latter study examined the number of NTD cases between the years 1998 and 2007.…”

“…Some studies have shown that the decrease in the number of spina bifida cases is greater than the decrease in anencephaly cases (15,21,30,32,36,37) ; however, other studies have shown a greater reduction in the latter (16,23,26,35,39,40) .…”

Craniorachischisis: first case reported in Madagascar

“…It has been shown to be an effective means of lowering recurrence risks for future pregnancies. 12,18,19 But this supplementation was not effective in our patient because anencephaly had recurred in the second child, associated with a rachischisis. Depending on the sex of the affected fetus, Lalouel JM and al evaluated that the risk of recurrence of NTDs is multiplied by 0.051 after one female affected, by 0.058 after one male affected.…”

“…One case of NTDs recurrence in group without prevention was similar with our case report, the first child had a spina bifida and the second a craniorachischisis. 19 Concerning the diagnostic means, craniorachischisis can be detected on ultrasound at gestational age of 13 weeks and magnetic resonance imaging at 22 weeks. 2,11 In our case, the rachischisis was diagnosed at birth.…”

Folic acid fortification and prevalences of neural tube defects, orofacial clefts, and gastroschisis in California, 1989 to 2010

“…Several studies have since examined whether fortification led to a reduction in NTD prevalence in the population as a before-versus-afterintervention-phenomenon. Most studies have indeed observed a reduction associated with the timing of fortification (Honein et al, 2001;Feldkamp et al, 2002;Williams et al, 2002;Canfield et al, 2005;Williams et al, 2005;Boulet et al, 2008;L opez-Camelo et al, 2010;Collins et al, 2011).…”