We hypothesize , therefore , that zinc homeostatic adjustments during pregnancy and lactation improve zinc utilization sufficiently to provide the increased zinc needs in these stages and , therefore , mitigate immediate detrimental effects due to a low zinc intake .
Zinc plays critical roles during embryogenesis , fetal growth , and milk secretion , which increase the zinc need for pregnancy and lactation .
Increased needs can be met by increasing the dietary zinc intake , along with making homeostatic adjustments in zinc utilization .
Potential homeostatic adjustments include changes in circulating zinc , increased zinc absorption , decreased zinc losses , and changes in whole body zinc kinetics .
Although severe zinc deficiency during pregnancy has devastating effects , systematic review s and meta- analysis of the effect of maternal zinc supplementation on pregnancy outcomes have consistently shown a limited benefit .
The specific questions addressed are the following : How is zinc utilization altered during pregnancy and lactation ?
Are those homeostatic adjustments influenced by maternal zinc status , dietary zinc , or zinc supplementation ?
A study of the effect of oral zinc supplementation during pregnancy on pregnancy outcome.
Women in different trimesters of pregnancy ( Group B ; n = 106 ) were administered 200 mg zinc sulphate ( elemental Zn 45 mg ) orally/day from the day of reporting till delivery . Untreated group of 62 served as control . Levels of zinc in maternal serum , umbilical cord blood serum , and urine were estimated . Pregnancy outcome was assessed in terms of incidence of prematurity , IUGR , birth weight ; apgar score and gestational age . Serum zinc levels in Gp . A declined significantly from 113.00 + /- 2.80 ug/dl in I trimester to 83.78 + /- 2.20 ug/dl in III ( P < 0.001 ) . Following zinc supplementation ( Gp . B ) serum zinc levels increased significantly from 109.70 + 3.23 micrograms/dl to 205.40 + /- 4.47 micrograms/dl ( P < 0.001 ) . Urinary excretion of zinc in Gp . A declined significantly with increase in the period of gestation . However in Gp . B , elimination of Zn increased significantly in proportion with the serum levels ( P < 0.001 ) cord blood serum zinc level was normal irrespective of maternal serum Zn levels . Following oral Zn supplementation , levels increased significantly from below 127.0 micrograms/dl to above 158.0 micrograms/dl in Gp . B ( P < 0.001 ) . Maternal serum and cord blood serum zinc ratios were fairly constant in Gp . A as well as in Gp . B. Birth weight of babies born with Zn supplementation was significantly higher than control and was related to duration of oral zinc supplementation ( P < 0.001 ) . Gestational age of babies in Gp . B was significantly higher than respective controls when Zn supplementation was given for more than 3 months ( P < 0.01 ) , and was related to duration of zinc therapy ( P < 0.05 ) . ( ABSTRACT TRUNCATED AT 250 WORDS
We hypothesize , therefore , that zinc homeostatic adjustments during pregnancy and lactation improve zinc utilization sufficiently to provide the increased zinc needs in these stages and , therefore , mitigate immediate detrimental effects due to a low zinc intake .
Zinc plays critical roles during embryogenesis , fetal growth , and milk secretion , which increase the zinc need for pregnancy and lactation .
Increased needs can be met by increasing the dietary zinc intake , along with making homeostatic adjustments in zinc utilization .
Potential homeostatic adjustments include changes in circulating zinc , increased zinc absorption , decreased zinc losses , and changes in whole body zinc kinetics .
Although severe zinc deficiency during pregnancy has devastating effects , systematic review s and meta- analysis of the effect of maternal zinc supplementation on pregnancy outcomes have consistently shown a limited benefit .
The specific questions addressed are the following : How is zinc utilization altered during pregnancy and lactation ?
Are those homeostatic adjustments influenced by maternal zinc status , dietary zinc , or zinc supplementation ?