Anticonvulsant drug therapy in human pregnancy: effects on serum concentrations of vitamin D metabolites in maternal and cord blood.
Serum concentrations of the main vitamin D metabolites and of calcium, phosphate, and alkaline phosphatase were determined in each of the three trimesters of pregnancy and in simultaneously obtained maternal and cord blood at delivery in 22 epileptic women treated with diphenylhydantoin or carbamazepine alone or with a combination with one other drug. The results were compared with similarly obtained data from 22 normal pregnancies. Women in both groups received supplements of 400 IU vitamin D3 per day. All the women had 25-hydroxyvitamin D levels within the normal range for healthy adults (greater than 12 ng/ml) throughout pregnancy. The epileptic women had, however, significantly (p less than 0.05) lower median 25-hydroxyvitamin D and 1,25-dihydroxyvitamin D levels and higher median 25,26-dihydroxyvitamin D values than the reference group. The 24,25-dihydroxyvitamin D concentrations did not differ significantly, but the median ratio of 24,25-dihydroxyvitamin D to 25-hydroxyvitamin D was higher in the epileptic women at the end of pregnancy (p = 0.05). The respective differences in cord serum concentrations reflected those of the mothers at delivery. Serum calcium tended to be lower during epileptic pregnancy, but none were hypocalcemic. The alkaline phosphatase and phosphate values did not consistently differ from those of the reference women. The median alkaline phosphatase level of cord serum was slightly higher in the epileptic group, but the calcium and phosphate levels were similar to the reference values. The various biochemical parameters of the carbamazepine-treated women tended to be intermediate between those of the healthy and diphenylhydantoin-treated groups. Antiepileptic drug therapy appears to affect vitamin D metabolism and calcium homeostasis during pregnancy. The derangements may not be of major clinical significance, however, in vitamin D-supplemented and normally functioning women on long-term low-dose therapy.
D015650:24,25-Dihydroxyvitamin D 3; D000293:Adolescent; D000328:Adult; D000469:Alkaline Phosphatase / Q000097:blood; D000927:Anticonvulsants / Q000494:pharmacology*; D002112:Calcifediol / Q000097:blood; D002117:Calcitriol / Q000097:blood; D002118:Calcium / Q000097:blood / Q000378:metabolism; D002220:Carbamazepine / Q000494:pharmacology; D002762:Cholecalciferol / Q000008:administration & dosage; D004100:Dihydroxycholecalciferols / Q000097:blood; D004827:Epilepsy / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D005260:Female; D005312:Fetal Blood / Q000032:analysis*; D006706:Homeostasis; D006801:Humans; D010672:Phenytoin / Q000494:pharmacology; D010710:Phosphates / Q000097:blood; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000188:drug therapy* / Q000378:metabolism; D014807:Vitamin D / Q000378:metabolism*
D000927:Anticonvulsants; D004100:Dihydroxycholecalciferols; D010710:Phosphates; D014807:Vitamin D; D002762:Cholecalciferol; D002220:Carbamazepine; D015650:24,25-Dihydroxyvitamin D 3; D010672:Phenytoin; D000469:Alkaline Phosphatase; D002117:Calcitriol; D002112:Calcifediol; C026032:25,26-dihydroxycholecalciferol; D002118:Calcium