Vitamin D requirements during pregnancy and lactation
It is extremely important that pregnant and nursing women obtain sufficient vitamin D from solar UVB exposure and/or vitamin D supplements to raise their serum 25-hydroxyvitamin D [25(OH)D] concentration to the range of 40-60 ng/ml (100-150 nmol/l). The reasons include the requirement for proper development of the fetus; for the mother, reduced risk of infections such as influenza during pregnancy, reduced risk of vaginal bacteriosis, pre-eclampsia, primary Cesarean section; for the fetus or infant - premature delivery, low birth weight, birth defects, autism, schizophrenia, type 1 diabetes mellitus, rickets. To reach the 40-60 ng/ml takes about 4000 IU/d vitamin D3. Bruce Hollis, Carol Wagner and colleagues have demonstrated that that intake is entirely safe and does not affect calcium concentrations in either the serum or urine. There is considerable person-to-person variability between serum 25(OH)D concentrations and oral intake, so pregnant women are advised to have their concentration checked. One’s doctor can order that test. Tests are also available as a mail-in kit for about $70 through Grassrootshealth.net and VitaminDCouncil.org. The kit includes a lance to prick a finger and a piece of paper for three blood spots. I have compared the results of the ZRT Labs. blood spot test with those of LabCorps and Quest, finding them to agree within 3%, which is normal experimental error.