Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
5
pubmed:dateCreated
1975-5-21
pubmed:abstractText
Calcium metabolism in pregnancy is a complex process involving calcium, phosphorus, vitamin D, parathyroid hormone (PTH), and calcitonin (CT). Calcium absorption is enhanced in pregnancy, and increased storage in the maternal skeleton probably occurs as well. Adequate amounts are provided by the current Recommended Dietary Allowance of 1,200 mg. daily which can be met readily by natural foods, specifically milk. If supplemental calcium is given, a nonphosphate salt is probably advisable, since some evidence suggests that excessive phosphate intake may be related to leg cramps in pregnancy. Vitamin D is necessary for optimal calcium utilization in pregnancy, although the possibility of fetal toxicity with overdosage has been suggested. From a review of available information with respect to maternal-perinatal calcium interrelationships, I propose the following hypothesis: While total maternal serum calcium declines during pregnancy because of the physiologic hypoalbuminemia, the level of ionic calcium remains constant, in part, at least, because of increasing maternal PTH output. The placenta plays a primary role in fetal calcium metabolism by transporting calcium ions from the mother to the fetus against a concentration gradient. Relatively high fetal ionic calcium levels cause suppression of PTH and stimulation of CT in the fetus, facilitating growth of the fetal skeleton. With sudden loss of the placental source of calcium at birth, the newborn infant becomes functionally hypoparathyroid and/or hypercalcitonemic, and the serum calcium level declines until 3 to 4 days of life when PTH rises and CT falls with a resultant slight rise in calcium.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
AIM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0002-9378
pubmed:author
pubmed:issnType
Print
pubmed:day
1
pubmed:volume
121
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
724-37
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:1090175-Animals, pubmed-meshheading:1090175-Bone Resorption, pubmed-meshheading:1090175-Bone and Bones, pubmed-meshheading:1090175-Calcitonin, pubmed-meshheading:1090175-Calcium, pubmed-meshheading:1090175-Calcium, Dietary, pubmed-meshheading:1090175-Calcium Radioisotopes, pubmed-meshheading:1090175-Dairy Products, pubmed-meshheading:1090175-Endocrine System Diseases, pubmed-meshheading:1090175-Female, pubmed-meshheading:1090175-Humans, pubmed-meshheading:1090175-Hypercalcemia, pubmed-meshheading:1090175-Hypocalcemia, pubmed-meshheading:1090175-Infant, Newborn, pubmed-meshheading:1090175-Infant, Newborn, Diseases, pubmed-meshheading:1090175-Intestinal Absorption, pubmed-meshheading:1090175-Maternal-Fetal Exchange, pubmed-meshheading:1090175-Milk, pubmed-meshheading:1090175-Muscle Cramp, pubmed-meshheading:1090175-Parathyroid Hormone, pubmed-meshheading:1090175-Phosphorus, pubmed-meshheading:1090175-Pregnancy, pubmed-meshheading:1090175-Pregnancy Complications, pubmed-meshheading:1090175-Pregnancy Trimester, First, pubmed-meshheading:1090175-Pregnancy Trimester, Second, pubmed-meshheading:1090175-Pregnancy Trimester, Third
pubmed:year
1975
pubmed:articleTitle
Calcium metabolism in pregnancy: a review.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Review