Untreated idiopathic hypoparathyroidism associated with infant congenital and perinatal abnormalities

Hypoparathyroidism and pseudohypoparathyroidism in pregnancy: an Italian retrospective observational study

Background

Hypoparathyroidism (HypoPT) or pseudo-hypoparathyroidism (pseudo-HypoPT) during pregnancy may cause maternal and fetal/neonatal complications. In this regard, only a few case reports or case series of pregnant or lactating women have been published. The purpose of this study was to describe clinical and biochemical course, pharmacological management, and potential adverse events during pregnancy and post-partum in pregnant women with HypoPT or pseudo-HypoPT. This was a retrospective, observational, multicenter, study involving nine Italian referral centers for endocrine diseases affiliated with the Italian Society of Endocrinology and involved in “Hypoparathyroidism Working Group”.

Results

This study identified a cohort of 28 women (followed between 2005 and 2018) with HypoPT (n = 25, 84% postsurgical, 16% idiopathic/autoimmune) and pseudo-HypoPT (n = 3). In HypoPT women, the mean calcium carbonate dose tended to increase gradually from the first to third trimester (+ 12.6%) in pregnancy. This average increase in the third trimester was significantly greater compared to the pre-pregnancy period (p value = 0.03). However, analyzing the individual cases, in 44% the mean calcium dosage remained unchanged throughout gestation. Mean calcitriol doses tended to increase during pregnancy, with a statistically significant increase between the third trimester and the pre-pregnancy period (p value = 0.02). Nevertheless, analyzing the individual cases, in the third trimester most women with HypoPT (64%) maintained the same dosage of calcitriol compared to the first trimester. Both mean calcium carbonate and calcitriol doses tended to decrease from the third trimester to the post-partum six months. Most identified women (~ 70%) did not display maternal complications and (~ 90%) maintained mean serum albumin-corrected total calcium levels within the low-to-mid normal reference range (8.5 ± 0.8 mg/dl) during pregnancy. The main complications related to pregnancy period included: preterm birth (n = 3 HypoPT women), and history of miscarriages (n = 6 HypoPT women and n = 2 pseudo-HypoPT women).

Conclusion

This study shows that mean serum albumin-corrected total calcium levels were carefully monitored during pregnancy and post-pregnancy, with limited evaluation of other biochemical parameters, such as serum phosphate, 24 h urinary calcium, 25-OH vitamin D, and creatinine clearance. To avoid complications in mothers affected by (HypoPT) or (pseudo-HypoPT) and offspring, intense biochemical, clinical and pharmacological monitoring during pregnancy and breastfeeding is highly recommended.

Hypoparathyroidism in Pregnancy and Lactation: Current Approach to Diagnosis and Management

Background: Hypoparathyroidism is an uncommon endocrine disorder. During pregnancy, multiple changes occur in the calcium-regulating hormones, which may affect the requirements of calcium and active vitamin D during pregnancy in patients with hypoparathyroidism. Close monitoring of serum calcium during pregnancy and lactation is ideal in order to optimize maternal and fetal outcomes. In this review, we describe calcium homeostasis during pregnancy in euparathyroid individuals and also review the diagnosis and management of hypoparathyroidism during pregnancy and lactation. Methods: We searched the MEDLINE, CINAHL, EMBASE, and Google scholar databases from 1 January 1990 to 31 December 2020. Case reports, case series, book chapters, and clinical guidelines were included in this review. Conclusions: During pregnancy, rises in 1,25-dihydroxyvitamin D (1,25-(OH)2-D3) and PTH-related peptide result in suppression of PTH and enhanced calcium absorption from the bowel. In individuals with hypoparathyroidism, the requirements for calcium and active vitamin D may decrease. Close monitoring of serum calcium is advised in women with hypoparathyroidism with adjustment of the doses of calcium and active vitamin D to ensure that serum calcium is maintained in the low-normal to mid-normal reference range. Hyper- and hypocalcemia should be avoided in order to reduce the maternal and fetal complications of hypoparathyroidism during pregnancy and lactation. Standard of care therapy consisting of elemental calcium, active vitamin D, and vitamin D is safe during pregnancy.

Changes in treatment needs of hypoparathyroidism during pregnancy and lactation: A case series

OBJECTIVE

As only sparse data are available, we aimed to investigate whether needs for activated vitamin D and calcium supplements change in women with hypoparathyroidism during pregnancy and lactation and risk of pregnancy-related complications.

DESIGN

Retrospective review of medical records.

PATIENTS

Twelve Danish and Canadian patients with chronic hypoparathyroidism who completed 17 pregnancies.

MEASUREMENTS

Data were extracted on plasma levels of ionized calcium (P-Ca²⁺ ) and doses of active vitamin D and calcium supplements during pregnancy (N = 14) and breastfeeding (N = 10). Data on pregnancy complications were available from all 17 pregnancies.

RESULTS

Although average doses of active vitamin D (P = .91) and calcium supplements (P = .43) did not change during pregnancies, a more than 20% increase or decrease in dose of active vitamin D was needed in more than half of the pregnancies in order to maintain normocalcemia. Five women (36%) developed hypercalcaemia by the end of pregnancy or start of lactation. Median levels of P-Ca²⁺ increased from 1.20 mmol/L in third trimester to 1.32 mmol/L in the post-partum period (P < .03). Accordingly, the average dose of active vitamin D was significantly reduced (P = .01) during lactation compared to 3rd trimester. One woman developed severe pre-eclampsia (6%). Further four pregnancies (24%) were complicated by polyhydramnios, dystocia and/or perinatal hypoxia. Ten pregnancies required caesarean delivery (59%) with four (24%) being performed as an emergency.

CONCLUSION

In chronic hypoparathyroidism, close medical monitoring of the mother with frequent adjustments in the dose of calcium and active vitamin D is required during pregnancy and lactation in order to maintain normocalcemia. Patients should be offered close obstetric care to handle potential perinatal complications. We recommend evaluating the neonate immediately after birth and notifying the paediatrician of the risks of hypocalcaemia as well as hypercalcaemia in the neonate.

Management of hypoparathyroidism in pregnancy and lactation - A report of 10 cases

INTRODUCTION

Hypoparathyroidism in pregnancy is rare, but important, as it is associated with maternal morbidity and foetal loss. There are limited case reports and no established management guidelines. Optimal maintenance of calcium levels during pregnancy is required to minimise the risk of related complications. This study aims to identify causes and examine outcomes of hypoparathyroidism in pregnancy in a cohort of women delivering at a large referral centre.

DESIGN AND METHOD

The Monash Health maternity service database captures pregnancy and birthing outcomes in over 9000 women each year. We audited this database between 2000 and 2014 to examine the clinical course, treatment and outcomes of pregnant women with hypoparathyroidism.

RESULTS

We identified 10 pregnancies from 6 women with pre-existing hypoparathyroidism secondary to idiopathic hypoparathyroidism (n = 3), autosomal dominant branchial arch disorder with hypoparathyroidism (n = 3) and autosomal dominant hypocalcaemia (n = 1), surgery for thyroid cancer (n = 2) and Graves' disease (n = 1). Maternal calcium levels were monitored through pregnancy and management adjusted to maintain normocalcaemia. One woman was delivered by caesarean section at 34 weeks' gestation because of intrauterine growth restriction, and oligohydramnios complicated two other pregnancies. The postpartum period was complicated by severe hypercalcaemia in one woman and by symptomatic, labile serum calcium levels during lactation in another woman, requiring close monitoring over a 6 month period.

CONCLUSION

Although rare, hypoparathyroidism in pregnancy poses a management challenge for clinicians, and co-ordinated care is required by obstetricians and endocrinologists to ensure optimal outcomes for both mother and baby. Continued monitoring of maternal calcium levels during lactation and weaning is essential to avoid the potential complications of either hypercalcaemia or hypocalcaemia.