Endocrine Abstracts

Introduction: Newly diagnosed primary hypoparathyroidism during pregnancy has been reported rarely. We recently encountered a first presentation of maternal hypoparathyroidism that was complicated by acute maternal and fetal hypocalcaemia.

Clinical presentation: A 36-year-old lady presented with hypocalcaemia at delivery of her third child. While early antenatal progress was uncomplicated she was admitted at 36 weeks gestation with pre-eclampsia and supraventricular tachycardia (Ca 0.98, Phos 2.38 mmol/l, ALP 306 U/l, Alb 20 g/l). Hypoparathyroidism was confirmed biochemically (PTH <10 pg/ml); she later recalled muscle cramps and carpopedal spasm for 10 years.

She delivered a male infant by emergency caesarean section at 36 weeks gestation. The child was hypocalcaemic (Ca 1.33 mmol/l, PTH 2229 pg/ml), had soft suture lines, enlarged fontanelles and was limp at delivery. He was treated with calcium, total parental nutrition (Day 5 PTH 498 pg/ml) and subsequently bottle fed prior to discharge after 2 weeks (Ca 2.4 mmol/l, ALP 784 U/l). Six weeks later his skull was mineralising while treated with vitamin D supplementation.

Discussion: Pregnancy is associated with dynamic changes in calcium concentrations and calcitropic hormones leading to accrual of around 30 g of fetal skeletal calcium by term. Satisfactory fetal outcomes usually are achieved with calcium and vitamin D replacement for mothers with known hypoparathyroidism. Early diagnosis and adequate calcium and vitamin D replacement may avert secondary hyperparathyroidism and fetal skeletal de-mineralisation in unrecognised cases such as these.