The pathophysiology of magnesium, the second highest common compound in humans, is still unclear, especially in preterm babies. We accessed the association between total magnesium (tMg), ionized Mg (iMg), and gestational age (GA) and that between serum magnesium (sMg) and intraventricular hemorrhage (IVH) in preterm babies.

In all, 119 inborn preterm infants admitted between July 2006 and February 2008 were divided into the IVH group (19) and the control group (100) and were prospectively analyzed. TMg, iMg, pH, total calcium (tCa), and ionized Ca (iCa) levels were determined immediately after delivery or within 3 hours after birth, and their correlation with GA were investigated.

TMg was not correlated with GA, tCa, iCa, and pH. IMg was correlated with tMg (r=0.288, P =0.002) and iCa (r=0.212, P =0.021); however, it was not correlated with GA and pH. Mean GA and birth weight were significantly lower ( P =0.002) and smaller ( P =0.030) in the IVH group. Mean sMg was higher in the IVH group (2.5±0.9 mg/dL) than in the control group (2.1±0.6 mg/dL) ( P =0.021). SMg was a risk factor even after logistic regression analysis (OR, 2.798; 95% C.I., 1.265-6.192; P =0.011).

In less than 37-week-old preterm babies, tMg and iMg were similar, regardless of GA. High sMg may be a risk factor for IVH in premature babies, regardless of their exposure to antenatal magnesium.