The relationship between maternal serum magnesium level and preterm birth.

The aim of this study was to evaluate the relationship between maternal serum magnesium levels and preterm birth. This Nested case-control study carried out on 20 with preterm birth and 20 women at term birth at Imam Khomeini Hospital in Sari/Iran in 2008. The women with singleton gestation and intact fetal membrane suspected to preterm labor (case group), 10 cc blood samples were drawn into syringes and sent to laboratory of the hospital immediately. Sampling for control group was same as the case group. These samples recognized as control group just as birth occurring after week 37. Finally, serum magnesium level measured. Data analyzed using chi2, t-test and OR (Odd's Ratio). There was a relationship between the number of prenatal visits (p = 0.008) and stressful events associated with preterm birth (p < 0.02). Serum magnesium level was associated with preterm birth OR = 4.75, CI 95% = (0.48-46.91), Sensitivity, specificity, positive and negative predictive value of serum magnesium for preterm birth was 95, 50, 66.5 and 83.33%, respectively. Although, there was a correlation between serum magnesium levels and preterm birth, due to methodology of the study, a cohort study with the same cut off point and supplementation of magnesium in RTC studies is recommended.