It is important to note, however, that the patient described by Sweeney et al. [21] received magnesium sulphate for pre-eclampsia; magnesium is a known cause of hypocalcemia (as demonstrated in the case report by Krysiak et al. [22]) due to inhibition of the tubular reabsorption of calcium (magnesium further inhibits the release of PTH, but the secretion of this latter hormone is already deficient in the patient). Here, PTH is linked to Hypocalcemia.