Magnesium concentration in amniotic fluid in the early weeks of the second trimester of pregnancy.

BACKGROUND: We analyse magnesium levels in amniotic fluid to establish normal values for the 14th to 18th week of pregnancy and establish critical values that could be useful diagnostic and therapeutic guidelines for possible complications.
FINDINGS: Ninety-two samples of amniotic fluid obtained by amniocentesis as well as the corresponding serum samples of pregnant women were analysed. The gestational age (mean ± SD) at which the amniotic fluid sample was obtained was 16.13 ± 1.87 weeks. Magnesium levels were determined by colorimetric assay with chlorophosphonazo-III using the the Cobas c 501 analyser (Roche Diagnostics). Statistical treatment of data was performed using the SPSS program, version 15.0.Results revealed a mean magnesium value of 1.65 ± 0.16 mg/dL in amniotic fluid and 1.97 ± 0.23 mg/dL in serum.
CONCLUSIONS: It would be interesting to extend the study to a larger number of pregnant women to determine variations in normal magnesium values in the three trimesters of pregnancy.