|Title||Micronutrient status and effects of supplementation in anemic pregnant women in China|
|Source||Wageningen University. Promotor(en): Evert Schouten; Frans Kok. - S.l. : s.n. - ISBN 9789461734938 - 148|
Nutrition and Disease
|Publication type||Dissertation, internally prepared|
|Keyword(s)||ijzergebrekanemie - zwangerschap - vitaminetoevoegingen - minerale supplementen - voedingstoestand - china - iron deficiency anaemia - pregnancy - vitamin supplements - mineral supplements - nutritional state - china|
Iron deficiency anemia (IDA) is a major nutrition related problem in China, especially affecting pregnant women,like in most developing countries. Deficiencies of vitamins also play an important role, such that iron, retinol and riboflavin deficiencies tend to coexist in anemic pregnant women. However, vitamin and/or mineral supplements are not routinely used by pregnant women at or below low income levels. Besides being an essential trace element, iron plays a central role in oxygen radical generation, whereas susceptibility during pregnancy is elevated. There is evidence that both iron deficiency and excess may result in free radical damage.
Based on this background, objectives of this thesis were to investigate the current prevalence of anemia among pregnant women in different sites of China, and todescribe the micronutrient status of anemic and non-anemic pregnant women in China. In addition, in anemic pregnant women, the effect of retinol and riboflavin supplementation on top of iron plus folic acid on anemia and changes in hematological status wasassessed. Also oxidative stress and erythrocyte membrane fluidity were evaluated. Finally, we compared the effect of sodium iron ethylenediaminetetraacetate (NaFeEDTA) and ferrous sulfate on hemoglobin (Hb), iron bioavailability and oxidative stress.
Subjects and Methods
A total of 6413 women in their third trimester of pregnancy were recruited from five rural areas in China (years 2000~2003) for screening anemia or iron deficiency. A random subset was selected for measuring micronutrient status. In three supplementation trials, effects of iron, folic acid, retinol and riboflavin were assessed among anemic pregnant women. Outcomes included hematological status, micronutrient status and parameters of oxidative stress. Samples of fasting blood were collected from subjects before and at the end of the interventions for measurements.
The overall prevalence of anemia was 58.6%, ranging between 48.1%~70.5% in the five areas. Serum concentrations of micronutrients were significantly lower in anemic women than non-anemic women. After the 2-mo intervention, the increase of Hb concentration in the group, supplemented with iron and folic acid combined with retinol and riboflavin, was 5.4g/L greater than in the group with iron and folic acid only (p<0.001). The reductions in the prevalence of anemia (Hb<110g/L) and iron deficiency anemia were significantly greater in the groups supplemented with retinol and/or riboflavin than in the iron and folic acidgroup. Riboflavin and/or retinol supplementation significantly improved gastrointestinal symptoms and well-being. In addition, supplementation of iron combined with retinol and riboflavin significantly decreased levels of serum malondialdehyde, and increased activities of glutathione peroxidase and erythrocyte membrane fluidity as well. NaFeEDTA supplementation showed superior effectiveness.
Conclusion and recommendations
Deficiency of iron and micronutrients in combination appears to contribute to the high prevalence of anemia in pregnant women in rural China. Supplementation with iron, particularly in combination with vitamins improved hematologic status as well as oxidative stress. NaFeEDTA performed better than ferrous sulfate. Multi-micronutrient supplementation may be worthwhile for pregnant women in rural China. Further studies on food-based or supplement-based approaches are warranted to decrease anemia of Chinese pregnant women in the third trimester.