Neural tube defects in Latin America and the impact of fortification: a literature review.

OBJECTIVE: Data on the prevalence of birth defects and neural tube defects (NTD) in Latin America are limited. The present review summarizes NTD prevalence and time trends in Latin American countries and compares pre- and post-fortification periods to assess the impact of folic acid fortification in these countries. DESIGN: We carried out a literature review of studies and institutional reports published between 1990 and 2010 that contained information on NTD prevalence in Latin America. RESULTS: NTD prevalence in Latin American countries varied from 0·2 to 9·6 per 1000 live births and was influenced by methods of ascertainment. Time trends from Bogota, Costa Rica, Dominican Republic, Guatemala City, Mexico and Puerto Rico showed average annual declines of 2·5 % to 21·8 %. Pre- and post-fortification comparisons were available for Argentina, Brazil, Chile, Costa Rica, Puerto Rico and Mexico. The aggregate percentage decline in NTD prevalence ranged from 33 % to 59 %. CONCLUSIONS: The present publication is the first to review data on time trends and the impact of folic acid fortification on NTD prevalence in Latin America. Reported NTD prevalence varied markedly by geographic region and in some areas of Latin America was among the lowest in the world, while in other areas it was among the highest. For countries with available information, time trends showed significant declines in NTD prevalence and these declines were greater in countries where folic acid fortification of staples reached the majority of the population at risk, such as Chile and Costa Rica.

Risk factors for non-syndromic holoprosencephaly in the National Birth Defects Prevention Study.

Holoprosencephaly (HPE) is a complex structural brain anomaly that results from incomplete cleavage of the forebrain. The prevalence of HPE at birth is low, and risk factors have been difficult to identify. Using data from a large multi-state population-based case-control study, we examined risk factors for non-syndromic HPE. Data from maternal telephone interviews were available for 74 infants with HPE and 5871 controls born between 1997 and 2004. Several characteristics and exposures were examined, including pregnancy history, medical history, maternal diet and use of nutritional supplements, medications, tobacco, alcohol, and illegal substances. We used chi(2)-tests and logistic regression (excluding women with pre-existing diabetes) to examine associations with HPE. Except for diet (year before pregnancy) and sexually transmitted infections (STIs) (throughout pregnancy), most exposures were examined for the time period from the month before to the third month of pregnancy. HPE was found to be associated with pre-existing diabetes (chi(2) = 6.0; P = 0.01), aspirin use [adjusted odds ratio (aOR) = 3.4; 95% confidence interval (CI) 1.6-6.9], lower education level (aOR = 2.5; 95%CI 1.1-5.6), and use of assisted reproductive technologies (ART) (crude OR = 4.2; 95%CI 1.3-13.7). Consistent maternal folic acid use appeared to be protective (aOR = 0.4; 95%CI 0.2-1.0), but the association was of borderline statistical significance. While some of these findings support previous observations, other potential risk factors identified warrant further study.

Periconceptional use of weight loss products including ephedra and the association with birth defects.

BACKGROUND: : Weight loss products are frequently used by reproductive-aged women and these products may be taken (inadvertently or intentionally) during pregnancy. This study assessed the association between periconceptional use of weight loss products and major structural birth defects. METHODS: : Mothers of infants with birth defects (case infants) and a random sample of livebirths (control infants) born during the period 1998-2003 in 10 states participated in the National Birth Defects Prevention Study. Adjusted ORs (aORs) for the association between self-reported use of weight loss products and 23 categories of birth defects were calculated. RESULTS: : Mothers of control infants (2.4%) and 2.6% of mothers of case infants reported periconceptional use of weight loss products; 1.2% of mothers of control infants and 1.3% of mothers of case infants reported using an ephedra-containing product. Use of any weight loss product was associated with anencephaly (aOR 2.6; 95% CI: 1.3-5.3), dextro-transposition of the great arteries (aOR 2.1; 95% CI: 1.1-4.3), and aortic stenosis (aOR 3.4; 95% CI: 1.5-7.9). Use of products containing ephedra showed an increased aOR with anencephaly (aOR 2.8; 95% CI: 1.0-7.3), while other weight loss products were associated with dextro-transposition of the great arteries (aOR 1.8; 95% CI: 1.2-2.7), and aortic stenosis (aOR 2.1; 95% CI: 1.3-3.5). CONCLUSIONS: : These results suggest an association between periconceptional use of weight loss products and certain birth defects but the possible mechanism is not clear. This is the first finding of such an association and, because we examined a large number of exposure-outcome associations in a hypothesis-generating analysis, these results might have been due to chance.

Promoting pre-conceptional use of folic acid to Hispanic women: a social marketing approach.

OBJECTIVE: To develop a culturally appropriate communication initiative in an effort to promote the use of pre-conceptional folic acid among Hispanic women of childbearing age. The materials were designed to communicate information about the risks of neural tube defects and the value of folic acid supplementation before conception. METHODS: The initiative was developed using a social marketing approach. A series of focus groups were conducted with Hispanic women, particularly Mexican and Mexican-American women, to gain an understanding of their knowledge, attitudes, and behaviors regarding birth defects and folic acid. Additionally focus groups assessed women's preferences for existing folic acid education materials. Qualitative analysis of coded transcripts revealed key themes which were incorporated into a multi-media initiative. RESULTS: Critical themes of the research highlighted the need to include the role of partners and a sense of family in the promotions aimed at these groups. Another key component was the need to dispel myths which act as barriers to pre-conceptional folic acid use. Other important elements included in the media products were the need for Spanish and English versions, an explanation of neural tube defects, and a reference to the cost of the supplements. CONCLUSION: The final products of the initiative included Spanish and English versions of a brochure, photo-novella, and radio public service announcement. Pre-testing results showed women understood the message, thought the message was for women like them, and expected to begin taking a folic acid supplement. Results of the overall evaluation of the initiative are on-going.