Primary hyperparathyroidism (PHPT) affects 0.05% of pregnancies and has associated complications1. A 33-year-old, G1P0, patient was diagnosed with incidental PHPT at 24 weeks, following secondary screen for chronic hypertension. A parathyroid adenoma was identified on ultrasound. Because her hypercalcemia responded to hydration, medical management was attempted, with a plan for post-partum parathyroidectomy. Unfortunately, the patient developed early-onset pre-eclampsia with significant challenges in managing her hypercalcemia. She delivered at 36+6 weeks with no neonatal complications. Her hypercalcemia briefly resolved post-partum with discordant findings on parathyroid scintiscan, and her local surgical team discharged her. Endocrinology assessment again confirmed PHPT and she was re-referred for surgery. The patient subsequently conceived while awaiting a 4D-CT, with a serum calcium of 2.72 entering her current pregnancy.
No consensus guidelines exist on managing PHPT in pregnancy, and recommendations are based on expert opinion. Early literature suggested maternal complication rates as high as 68%, and neonatal complications at 80%. Two retrospective studies reviewed pregnant patients with PHPT and found no difference in neonatal mortality when compared to a normocalcemic cohort1,2. However, neither study reported on the prevalence of maternal hypertension, pre-eclampsia, renal dysfunction, fetal growth restriction, or neonatal hypocalcemia.
Studies assessing surgical vs medical management of PHPT in pregnancy have reported improved outcomes in the surgical group (reduced stillbirth rates and neonatal hypocalcemia) when parathyroidectomy is performed in the second trimester. Expert opinion unanimously favours curative surgery for PHPT prior to conception3,4,5. Disseminating this recommendation is paramount to ensuring the best outcomes for patients and their neonates.