[Effects of supplementing calcium, iron and zinc on the fetus development and growth during pregnancy]

Abstract

Objectives: The purpose of the present study is to determine the effects of supplementing the biscuits fortified with calcium (Ca), iron (Fe) and zinc (Zn) for pregnant women from the 5th month of gestation until delivery on the growth and development of fetus and to explore the best way to improve infant growth.

Methods: A total of 313 healthy and primary pregnant women were enrolled and divided into five study groups based on their order visiting the hospitals for prenatal care. Each woman of the study groups was given three pieces of biscuit fortified with VD, Ca and VD, Ca, Zn and VD (Ca + Zn + VD), Ca, Fe, VC and VD (Ca + Fe + VD), Ca, Fe, VC, Zn and VD (Ca + Fe + Zn + VD), respectively, from the 5th month of gestation until delivery (24 weeks in total) daily. The fortified levels were 10 micrograms Ca from carbonate calcium, 10 mg Zn from lactate zinc, 10 mg Fe from ferrous lactate, and 50 mg VC, respectively. A parturient women was selected from the same hospital as control after one trial subject for each study groups selected. Placenta was weighed and umbilical cord venous blood and placenta tissue samples were collected after delivery for measuring Ca and other trace elements. Body weight and height of the new-born babies were measured.

Results: The weight of placenta in control group (551.1 +/- 64.2) g was significantly (P < 0.05) heavier than other trial groups with Ca + Fe + Zn + VD (467.1 +/- 36.6) g, but contents of Ca and other trace elements in placenta of the control group were lower, which probably because of the lower nutrients intake of mothers in control group that would result in a compensation enlargement of placenta to get enough nutrients for fetus from mother. The Hb level in cord venous blood was significantly higher than that of maternal blood. There was no significant difference in activity of alkaline phosphatase between cord venous blood and material blood. The contents of Ca, Fe and Zn in cord venous plasma were all significantly higher than those in maternal plasma. Birth weight and height in Ca + Fe + Zn + VD group were the highest in all the groups, with birth weight of (3.53 +/- 0.33) kg, as compared with (3.28 +/- 0.54) kg in the control group. There was significant correlation between birth weight, weight for age and intake of Ca, Fe and Zn during pregnancy.

Conclusion: Supplementation of Ca + Fe + Zn + VitD during pregnancy is the best way to improve infant development and growth, based on the current Recommended Dietary Allowances (RDA) for pregnant women.