Maternal osteoporosis after prolonged magnesium sulfate tocolysis therapy: a case report

Tocolysis therapy with magnesium sulfate is known to affect calcium homeostasis. Prolonged infusion of magnesium sulfate (MgSO(4)) has been used for the treatment of refractory preterm labor, and has been reported to change maternal calcium homeostasis and possible mineralization. In this case report, we present a woman in her mid thirties who had undergone intravenous MgSO(4) tocolysis therapy, and developed osteoporosis leading to significant morbidity after delivery. The laboratory investigation, including the bone scan, magnetic resonance image, indices of bone turnover, and the results of 2 years of follow-up of bone mineral density, are also reported. This case report supports the existence of a possible association between prolonged intravenous magnesium tocolysis and maternal osteoporosis. To prevent osteoporosis, it is important to avoid a prolonged period of MgSO(4) tocolysis. In cases of prolonged MgSO(4) treatment and bedrest, physicians should be aware of the risk of osteoporosis. The recommended management is also discussed in this report.