Hyperparathyroidism during pregnancy and the effect of rising calcium on pregnancy loss: a call for earlier intervention

Abstract

HPT during pregnancy is under recognized and is associated with a 3.5-fold increase in miscarriage rates. Pregnancy loss often occurs in the second trimester and is associated with multiple miscarriages when not addressed. Pregnancy loss is more common as calcium levels exceed 11.4 mg/dl (2.85 mmol/l), but can be seen at all elevated calcium levels. Emphasis is placed on earlier recognition and surgical cure before becoming pregnant, however, once pregnant, surgery should be offered early in the second trimester for those with calcium levels above 11.4 mg/dl.

Pregnancy outcomes in women with primary hyperparathyroidism

“…An association between gestational PHPT and pregnancy loss has been suggested, and so far only one study has been able to determine the rate of pregnancy loss in women with gestational PHPT (5). The study showed a 3.5 higher rate of spontaneous abortions in women with PHPT.…”

“…The existing literature describing the consequences of gestational PHPT is limited, and mainly consists of case reports or case series (1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28). In total, these studies reported 33 pregnancies in women with PHPT, who did not undergo surgery.…”

“…It has been reported that the rate of maternal complications during pregnancy associated with PHPT can be as high as 67%, most commonly being hyperemesis and nephrolithiasis (4,5). More severe complications such as pancreatitis and hypercalcaemic crisis have also been reported, although at extremely high serum calcium levels (6).…”

“…Although rare, gestational PHPT may have serious consequences for both mother and child (5,6,7). It has been reported that the rate of maternal complications during pregnancy associated with PHPT can be as high as 67%, most commonly being hyperemesis and nephrolithiasis (4,5).…”

Parathyroid surgery in pregnancy: review of the literature and localization by aspiration for parathyroid hormone levels

“…In contrast, 48% of pregnancies complicated by untreated hyperparathyroidism ended in a miscarriage, which was directly related to the degree of hypercalcemia. 34 An association between maternal hypercalcemia and fetal polyhydramnios, fetal demise and neonatal hypocalcemia was shown in another retrospective case series. 35 Thus, maternal hypercalcemia should be ruled out in women with a history of unexplained fetal loss, polyhydramnios, previous neonatal hypocalcemia or severe hyperemesis.…”