Status of plasma folate after folic acid fortification of the food supply in pregnant African American women and the influences of diet, smoking, and alcohol consumption.

BACKGROUND: African American women and socioeconomically challenged women are at risk of compromised folate status and, thus, of folate-related birth defects. Data are limited on circulating folate concentrations in pregnant African American women after folic acid fortification of the food supply was implemented. OBJECTIVE: The objective was to determine the influence of smoking and alcohol consumption on plasma 5-methyltetrahydrofolic acid (5-MTHFA) concentrations in pregnant African American women. DESIGN: Alcohol consumption, smoking exposure, and other characteristics of pregnant African American women reporting to an inner-city antenatal clinic were assessed. At 24 wk of gestation, blood samples and food-frequency intake data were collected. Plasma 5-MTHFA concentrations were determined by liquid chromatography-mass spectrometry for 116 subjects and examined in a correlational study design. RESULTS: Dietary folate and markers of alcohol consumption were positively associated, whereas exposure to smoke was negatively associated with plasma 5-MTHFA. More than one-half of the participants in this population failed to meet the recommended dietary allowance for dietary folate equivalents of 600 microg/d during pregnancy. CONCLUSIONS: Most inner-city African American women are not meeting the recommended dietary allowance for dietary folate during pregnancy, and smoking may further compromise their folate status. Programs to reduce smoking and raise awareness about the importance of folate and multivitamin supplementation during pregnancy need to target this population.

Effects of alcohol intake during pregnancy on docosahexaenoic acid and arachidonic acid in umbilical cord vessels of black women.

OBJECTIVE: Alcohol influences the intake and metabolism of several nutrients including long-chain polyunsaturated fatty acids (LC-PUFAs). The LC-PUFAs docosahexaenoic acid (DHA) and arachidonic acid (AA) are particularly crucial for intrauterine growth and brain development. We hypothesized that alcohol consumption adversely affects LC-PUFA levels in pregnant women and their newborn infants. METHODS: Pregnant black women (N = 208) presenting at a core city antenatal clinic were screened and recruited. Shortly before delivery, maternal plasma was collected. After delivery, umbilical arteries and veins were dissected from the cords, total lipids were extracted from the vessel tissues and maternal plasma, and fatty acid levels were assayed by gas chromatography. For statistical analysis, subjects were categorized according to absolute alcohol intake per day (AAD) and absolute alcohol intake per drinking day (AADD) around the time of conception, with smoking and other potential confounders included in the analyses. RESULTS: Significant differences in fatty acid composition of total lipid extracts were detected in umbilical cord vessels among the AADD groups: abstainers (AADD = 0), moderate drinkers (AADD < 130 g), and heavy drinkers (AADD > or = 130 g). DHA and AA content in the arterial umbilical vessel wall was approximately 14% and approximately 10% higher in the moderate (n = 127) and heavy (n = 32) alcohol groups, respectively, than in abstainers (n = 49). A small, nonsignificant increase ( approximately 3%) was seen in the umbilical vein for AA but not for DHA. Alcohol intake was positively correlated to both DHA and AA concentrations in the arterial vessel wall but to neither in the venous wall nor maternal plasma. Maternal plasma DHA was positively correlated with both umbilical arteries and vein DHA, but there were no significant correlations for AA between maternal plasma and either umbilical vessel. CONCLUSIONS: Our findings indicate that alcohol intake during pregnancy is associated with altered DHA and AA status in fetal tissues. Although differences may be due to either metabolism and/or distribution, it is most likely a result of a direct influence of alcohol on fetal metabolism.

Comparison of bloodstream fatty acid composition from African-American women at gestation, delivery, and postpartum.

Our aim was to examine the docosahexaenoic acid (DHA; 22:6n-3) status of pregnant African-American women reporting to the antenatal clinic at Wayne State University in a longitudinal study design. Fatty acid compositions of plasma and erythrocyte total lipid extracts were determined and food frequency surveys were administered at 24 weeks of gestation, delivery, and 3 months postpartum for participants (n = 157). DHA (mean +/- SD) in the estimated total circulating plasma was similar at gestation (384 +/- 162 mg) and delivery (372 +/- 155 mg) but was significantly lower at 3 months postpartum (178 +/- 81 mg). The relative weight percentage of DHA and docosapentaenoic acid n-6 (DPAn-6; 22:5n-6) decreased postpartum, whereas their respective metabolic precursors, eicosapentaenoic acid (EPA; 20:5n-3) and arachidonic acid (AA; 20:4n-6), increased. Similar results were found in erythrocytes. Dietary intake of DHA throughout the study was estimated at 68 +/- 75 mg/day. The relative amounts of circulating DHA and DPAn-6 were increased during pregnancy compared with 3 months postpartum, possibly via increased synthesis from EPA and AA. The low dietary intake and blood levels of DHA in this population compared with others may not support optimal fetal DHA accretion and subsequent neural development.

Alcohol consumption in pregnant, black women is associated with decreased plasma and erythrocyte docosahexaenoic acid.

BACKGROUND: Inner-city, black women are among those groups that are at higher risk for having infants with fetal alcohol spectrum disorders that can include life-long neurobehavioral and cognitive impairments. Chronic alcohol consumption can decrease amounts of docosahexaenoic acid (DHA), a fatty acid that is essential for optimal infant neural and retinal development in a variety of tissues. METHODS: Black women who presented at an inner-city antenatal clinic for their first prenatal visit were recruited into a longitudinal, observational study. Alcohol intake was determined by a structured interview. Participants provided blood specimens and completed food frequency surveys at 24 weeks of gestation, infant delivery, and 3 months postpartum. Fatty acid composition analyses were completed on 307, 260, and 243 for plasma and 278, 261, and 242 erythrocyte specimens at 24 weeks of gestation, delivery, and 3 months postpartum, respectively. RESULTS: Proportion of drinking days at the first prenatal visit was associated with decreased DHA in plasma and erythrocytes throughout the study. This association was the strongest at 24 weeks of gestation. In addition, an interaction between proportion of drinking days at the time of conception and ounces of absolute alcohol per drinking day at the time of conception was detected and demonstrated that, in daily drinkers, high intakes of alcohol are associated with decreased DHA and arachidonic acid (AA) concentrations in plasma. CONCLUSIONS: Frequent and high intakes of alcohol that have been previously associated with fetal alcohol spectrum disorders are also associated with decreased maternal DHA and AA plasma concentrations. The present findings indicate that maternal DHA deficiency is associated with high-risk drinking and may contribute to the mechanism(s) of alcohol-related neurodevelopmental disorders.