The objective of this study was to estimate the incidence of complications when primary hyperparathyroidism (PHPT) is treated by parathyroidectomy in the third trimester of pregnancy. After searching the literature published through/including January 2005, we identified and analyzed 16 cases of PHPT treated surgically after 27 weeks of gestation. Parathyroid adenomas were detected in 81.2% of cases, hyperplasia in 6.3%, and carcinoma in 12.5%. Only one case failed surgical therapy. The postoperative incidence of clinically significant complications from the surgery was as low as 5.9% in fetuses and 0% in mothers. The incidence of clinically significant complications resulting from delayed diagnosis or postponed surgery ranged from 17.6% to 23.5% in fetuses and 18.8% to 25.0% in mothers. Postoperative hypocalcemia was detected in 62.5% of mothers and 17.6% of their newborns. All cases were easily treated with calcium replacement. Preeclampsia was diagnosed in 25% of cases. No clinically significant complications have been reported between 1993 and January 2005. This review suggests that parathyroidectomy performed in the third trimester of pregnancy is effective and has less risk than previously reported. Postponing surgery may be hazardous. Postoperative hypocalcemia is common but easily treated. Hyperparathyroidism should be considered a risk factor for preeclampsia.
Target audience: Obstetricians & Gynecologists, Family Physicians.
Learning objectives: After completion of this article, the reader should be able to summarize the maternal and fetal complications of a delayed diagnosis and/or postponed surgery, recall that surgery of a parathyroid tumor can be safely performed in the third trimester, and describe pregnancy complications of hyperparathyroidism.