Prolonged maternal magnesium administration and bone metabolism in neonates

Yokoyama, Koji; Takahashi, Naoto; Yada, Yukari; Koike, Yasunori; Kawamata, Ryou; Uehara, Ritei; Kono, Yumi; Honma, Yoko; Momoi, Mariko Y.

doi:10.1016/j.earlhumdev.2010.02.007

« Previous Next »Early Human Development
Volume 86, Issue 3 , Pages 187-191, March 2010

Prolonged maternal magnesium administration and bone metabolism in neonates

Koji Yokoyama
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Naoto Takahashi
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
- Corresponding author. Tel.: +81 285 58 7366; fax: +81 285 44 6123.
Yukari Yada
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Yasunori Koike
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Ryou Kawamata
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Ritei Uehara
- Department of Public Health, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Yumi Kono
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Yoko Honma
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan
Mariko Y. Momoi
- Department of Pediatrics, Jichi Medical University School of Medicine, 3311-1, Yakushiji, Shimotsuke, Tochigi 329-0498, Japan

Received 12 September 2009; received in revised form 17 February 2010; accepted 17 February 2010.

Abstract

Background

Magnesium sulfate (MgSO₄) has been used as a tocolytic agent in cases of refractory preterm labor. Prolonged maternal administration of MgSO₄ may induce bone demineralization in the neonate. However, the effects of MgSO₄ on serum biochemistry related to bone metabolism in neonates remain unclear.

Aim

To assess the effects of prolonged maternal administration of MgSO₄ on fetuses and neonates.

Study design

This retrospective case–control study examined 167 neonates. Cases comprised 58 neonates whose mothers had received intravenous MgSO₄ administration for >5days. Neonatal serum levels of magnesium (Mg), calcium (Ca), phosphorus (P) and alkaline phosphatase (ALP) were reviewed. We also investigated whether subject neonates showed appearance of osteopenia at the metaphyseal lines on radiography at birth.

Results

Mean serum Mg and P levels were significantly higher, and Ca levels were significantly lower, in cases than in controls at birth. Mean serum ALP level was 1188.5IU/l in cases, significantly higher than that in controls at birth. Bone abnormalities were noted on radiography in 2 subjects. By 3weeks old, serum ALP levels did not differ significantly between cases and controls. Logistic regression analysis revealed maternal administration of MgSO₄ and multiple pregnancies were significantly related to serum ALP level in neonates at birth.

Conclusion

Prolonged maternal administration of MgSO₄ significantly affects neonatal serum biochemistry related to bone metabolism. Potential long-term adverse effects on neonates and how Mg affects fetal bone metabolism in utero need to be investigated in future studies.

Keywords: Magnesium sulfate, Tocolysis, Neonate, Bone abnormality, Alkaline phosphatase