Parathyroid disorders of pregnancy

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.

Parental Multiple Endocrine Neoplasia Type 1 (MEN 1) Is Associated with Increased Offspring Childhood Mortality

CONTEXT

Information regarding the impact of parental multiple endocrine neoplasia type 1 (MEN 1) on neonatal outcomes is limited to case reports.

OBJECTIVE

To determine the impact of parental MEN 1 on neonatal outcomes.

METHODS

Retrospective cohort analysis of the Tasman 1 MEN 1 kindred stratified by whether birth occurred before ("historical cohort") or after ("contemporary cohort") prospective screening commenced. The historical cohort included kindred members born between 1825 and 1984 (n = 341 children with a MEN 1 positive (MEN 1+) parent and n = 314 children with MEN 1 negative (MEN 1-) parents). The contemporary cohort included neonates (n = 52) of MEN 1+ women (n = 21) managed at a tertiary referral hospital between 1985 and 2018.

RESULTS

Historical cohort: compared with MEN 1- parents, children of MEN 1+ parents were more likely to die postpartum (HR 4.6, P = .046 at 6 months of age). Excess mortality at 15 years of age was observed for children of MEN 1+ mothers (HR 8.50, P = .002) and fathers (HR 3.82, P = .03). Contemporary cohort: neonates of MEN 1+ mothers were more likely to have low birth weight (28.9% vs 6.7%, P = .01), be admitted to a higher care nursery (40.4% vs 17%, P = .02), and require a longer median postnatal stay (5 vs 4 days, P = .009) than the Australian average. Isolated antenatal hypercalcemia did not significantly alter neonatal outcomes.

CONCLUSION

Children with a MEN 1+ parent are disproportionately vulnerable postpartum. Neonates of MEN 1+ mothers remain vulnerable despite contemporary care. The excess risk was not fully explained by maternal MEN 1 or antenatal hypercalcemia.

Calcium Metabolic Disorders in Pregnancy: Primary Hyperparathyroidism, Pregnancy-Induced Osteoporosis, and Vitamin D Deficiency in Pregnancy

Physiologic changes during pregnancy include calcium, phosphate, and calciotropic hormone status. Calcium metabolic disorders are rare in pregnancy and management with close calcium and vitamin D control and supplementation. Primary hyperparathyroidism is mostly asymptomatic and does not affect conception or pregnancy. It requires control of plasma calcium levels. Surgical intervention may be indicated. Data on severe cases are missing. Osteoporosis in or before pregnancy is rare but usually diagnosed from fractures. Medical treatment other than supplementation is contraindicated. Vitamin D deficiency is common and may affect conception and increase complications. Current evidence does not prove vitamin D supplements effective in improving outcomes.

A rare lethal case of severe acute necrotizing pancreatitis due to a parathyroid adenoma in a third-trimester pregnant woman

BACKGROUND

Primary hyperparathyroidism (PHPT), which is mostly caused by a parathyroid adenoma, is fairly common in postmenopausal women but is relatively rare in pregnant women. PHPT-induced pancreatitis during pregnancy is associated with significant maternal and foetal morbidity and mortality. Diagnosis is challenging because of non-specific symptoms and changes in maternal calcium homeostasis. Information about the optimal treatment strategy for the prevention of catastrophic consequences to the mother and foetus is limited. Here, we describe a rare lethal case of severe acute necrotizing pancreatitis due to a parathyroid adenoma in a woman in her third trimester of pregnancy.

CASE PRESENTATION

A previously healthy 24-year-old Chinese woman at 37 weeks of gestation presented with persisting epigastric pain, nausea and bilious vomiting for 1 day. PHPT-induced acute necrotizing pancreatitis was diagnosed on the basis of her serum calcium, parathyroid levels and imaging results. A caesarean section and parathyroidectomy were performed at 1 day and 11 days after admission, respectively. Histological examination confirmed a right inferior parathyroid adenoma with a size of 2.0 × 1.5 cm. Following the parathyroidectomy, the patient had eucalcaemia and presented normal parathyroid hormone (PTH) levels. Although the foetus was normal, the patient died of multiple organ failure due to severe pancreatitis.

CONCLUSIONS

PHPT-induced acute necrotizing pancreatitis is a rare clinical entity and life-threatening condition to both the mother and the foetus during pregnancy. Early diagnosis can be challenging and is crucial. Appropriate treatment according to the patient's condition may effectively reduce maternal and foetal mortality.

Clinical Approach to Hypocalcemia in Newborn Period and Infancy: Who Should Be Treated?

Introduction

Hypocalcemia is a common metabolic problem in newborn period and infancy. There is consensus on the treatment of the symptomatic cases while the calcium level at which the treatment will be initiated and the treatment options are still controversial in asymptomatic hypocalcemia.

Methods

This review article will cover hypocalcemia with specific reference to calcium homeostasis and definition, etiology, diagnosis, and treatment of hypocalcemia in newborn and infancy period.

Results

Hypocalcemia is defined as total serum calcium <8 mg/dL (2 mmol/L) or ionized calcium <4.4 mg/dL (1.1 mmol/L) for term infants or preterm infants weighing >1500 g at birth and total serum calcium <7 mg/dL (1.75 mmol/L) or ionized calcium <4 mg/dL (1 mmol/L) for very low birth weight infants weighing <1500 g. Early-onset hypocalcemia is generally asymptomatic; therefore, screening for hypocalcemia at the 24th and 48th hour after birth is warranted for infants with high risk of developing hypocalcemia. Late-onset hypocalcemia, which is generally symptomatic, develops after the first 72 h and toward the end of the first week of life. Excessive phosphate intake, hypomagnesemia, hypoparathyroidism, and vitamin D deficiency are commonest causes of late-onset hypocalcemia. Hypocalcemia should be treated according to etiology. Calcium replacement is the cornerstone of the treatment. Elementary calcium replacement of 40 to 80 mg/kg/d is recommended for asymptomatic newborns. Elementary calcium of 10 to 20 mg/kg (1–2 mL/kg/dose 10% calcium gluconate) is given as a slow intravenous infusion in the acute treatment of hypocalcemia in patients with symptoms of tetany or hypocalcemic convulsion.

Conclusion

Since most infants with hypocalcemia are usually asymptomatic, serum total or ionized calcium levels must be monitored in preterm infants with a gestational age <32 weeks, small for gestational age infants, infants of diabetic mothers, and infants with severe prenatal asphyxia with a 1 min Apgar score of <4. The treatment of hypocalcemia should be initiated immediately in infants with reduced calcium levels while investigating the etiology.

Primary Hyperparathyroidism in Pregnancy: Maternofetal Outcomes at a Quaternary Referral Obstetric Hospital, 2000 Through 2015

CONTEXT

Primary hyperparathyroidism (PHPT) in pregnancy has historically been associated with substantial maternofetal morbidity and mortality rates. The optimal treatment and timing of surgical intervention in pregnancy remain contested.

OBJECTIVE

To compare maternofetal outcomes of medically and surgically treated patients with PHPT in pregnancy.

DESIGN

Retrospective chart review.

SETTING

Quaternary referral hospital.

PATIENTS

Women with PHPT in pregnancy treated between 1 January 2000 and 31 December 2015.

INTERVENTIONS

Medical therapy or parathyroid surgery.

MAIN OUTCOMES MEASURED

Timing of diagnosis; maternal corrected serum calcium concentrations; gestation, indication and mode of delivery; complications attributable to PHPT; birth weight; and admission to the neonatal intensive care unit (NICU).

RESULTS

Twenty-two pregnancies were managed medically, and six patients underwent parathyroidectomy in pregnancy (five in trimester 2, and one at 32 weeks gestation). Most patients treated medically either had a corrected serum calcium concentration <2.85 mmol/L in early pregnancy or had PHPT diagnosed in trimester 3. Of viable medically managed pregnancies, 30% were complicated by preeclampsia, and preterm delivery occurred in 66% of this group. All preterm neonates required admission to the NICU for complications related to prematurity. All surgically treated patients delivered their babies at term, and there were no complications of parathyroid surgery.

CONCLUSION

Maternofetal outcomes have improved relative to that reported in early medical literature in patients treated medically and surgically, but the rates of preeclampsia and preterm delivery were higher in medically treated patients. The study was limited by its retrospective design and small sample sizes.

Clinical presentation and management of hypoparathyroidism

The clinical manifestations of hypoparathyroidism are variable and can involve almost any organ system. The main clinical features of the hypoparathyroidism are typically signs or symptoms due to neuromuscular irritability owing to low serum calcium level. In addition to hypocalcemia, hyperphosphatemia can contribute to long-term complications, including extra-skeletal calcifications. Bone turnover markers are generally decreased, and bone mass density is usually normal-increased compared to age- and gender-matched controls. It is still unclear whether or not these bone features could have an impact on the risk of fracture. Impaired renal function is a common complication described in patients treated for hypoparathyroidism. Other complications include premature cataracts, seizures, basal ganglia calcifications, and cardiac arrhythmias. Lastly, some clinical studies have also reported a reduced quality of life of patients with hypoparathyroidism. Increased awareness of the clinical manifestations of this disease is important to improve its clinical management.

A case of severe acute necrotizing pancreatitis in a 38-year-old woman postpartum due to a parathyroid adenoma

Lethal necrotizing pancreatitis postpartum due to primary hyperparathyroidism caused by a parathyroid adenoma can be considered as a rarity. Due to the unspecific clinical signs and uncommonness this disorder may be overseen very easily. The reported case illustrates the very importance of early diagnosis of this endocrine disorder in pregnancy in order to avoid a lethal course.

A Young Woman With Recurrent Gestational Hypercalcemia and Acute Pancreatitis Caused by CYP24A1 Deficiency

The CYP24A1 gene encodes a mitochondrial 24-hydroxylase that inactivates 1,25(OH)₂ D. Loss-of-function mutations in CYP24A1 cause hypercalcemia, nephrolithiasis and nephrocalcinosis. We describe a woman with CYP24A1 deficiency and recurrent gestational hypercalcemia. Her first pregnancy, at age 20, resulted with the intrauterine demise of twin fetuses. Postpartum, she developed severe hypercalcemia (14 mg/dL), altered mental status, and acute pancreatitis. Her PTH was suppressed (6 pg/mL) and her 1,25(OH)₂ D was elevated (165 and 195 pg/mL on postpartum day 1 and 5, respectively). Between one and three months postpartum, her serum calcium decreased from 11.4 to 10.2 mg/dL while her 1,25(OH)₂ D level decreased from 83 to 24 pg/mL. Her 24-hour urine calcium was 277 mg. Six months postpartum, she became pregnant again. At 14 weeks, her albumin-corrected calcium level was 10.4 mg/dL and her 1,25(OH)₂ D level exceeded 200 pg/mL. To establish the diagnosis of CYP24A1 deficiency, we showed her 24,25(OH)₂ D level to be undetectable (<2 ng/mL). Exon sequencing of the CYP24A1 gene revealed a homozygous, 8-nucleotide deletion in exon 8, causing an S334V substitution and premature termination due to a frame shift (c.999_1006del, p.Ser334Valfs*9). To prevent hypercalcemia, she was advised to discontinue prenatal vitamins, avoid sun exposure and calcium-rich foods, and start omeprazole and a calcium binder (250 mg K-Phos-neutral with meals). Despite these measures, both hypercalcemia (11.5 mg/dL) and acute pancreatitis recurred. Labor was induced and a healthy, normocalcemic boy was delivered. In the absence of lactation, maternal hypercalcemia resolved within 2 months. This report shows that CYP24A1-deficient subjects may be normocalcemic at baseline. Hypercalcemia may be unmasked by pregnancy through the routine use of calciferol-containing prenatal vitamins, increased 1-alpha hydroxylation of VitD by the placenta and maternal kidney, and production of PTHrP by the uteroplacental unit. CYP24A1 deficiency should be considered in patients with unexplained vitamin D-mediated hypercalcemia. © 2016 American Society for Bone and Mineral Research.

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.

European Society of Endocrinology Clinical Guideline: Treatment of chronic hypoparathyroidism in adults

Hypoparathyroidism (HypoPT) is a rare (orphan) endocrine disease with low calcium and inappropriately low (insufficient) circulating parathyroid hormone levels, most often in adults secondary to thyroid surgery. Standard treatment is activated vitamin D analogues and calcium supplementation and not replacement of the lacking hormone, as in other hormonal deficiency states. The purpose of this guideline is to provide clinicians with guidance on the treatment and monitoring of chronic HypoPT in adults who do not have end-stage renal disease. We intend to draft a practical guideline, focusing on operationalized recommendations deemed to be useful in the daily management of patients. This guideline was developed and solely sponsored by The European Society of Endocrinology, supported by CBO (Dutch Institute for Health Care Improvement) and based on the Grading of Recommendations Assessment, Development and Evaluation (GRADE) principles as a methodological base. The clinical question on which the systematic literature search was based and for which available evidence was synthesized was: what is the best treatment for adult patients with chronic HypoPT? This systematic search found 1100 articles, which was reduced to 312 based on title and abstract. The working group assessed these for eligibility in more detail, and 32 full-text articles were assessed. For the final recommendations, other literature was also taken into account. Little evidence is available on how best to treat HypoPT. Data on quality of life and the risk of complications have just started to emerge, and clinical trials on how to optimize therapy are essentially non-existent. Most studies are of limited sample size, hampering firm conclusions. No studies are available relating target calcium levels with clinically relevant endpoints. Hence it is not possible to formulate recommendations based on strict evidence. This guideline is therefore mainly based on how patients are managed in clinical practice, as reported in small case series and based on the experiences of the authors.

Preconception care: screening and management of chronic disease and promoting psychological health

INTRODUCTION

A large proportion of women around the world suffer from chronic diseases including mental health diseases. In the United States alone, over 12% of women of reproductive age suffer from a chronic medical condition, especially diabetes and hypertension. Chronic diseases significantly increase the odds for poor maternal and newborn outcomes in pregnant women.

METHODS

A systematic review and meta-analysis of the evidence was conducted to ascertain the possible impact of preconception care for preventing and managing chronic diseases and promoting psychological health on maternal, newborn and child health outcomes. A comprehensive strategy was used to search electronic reference libraries, and both observational and clinical controlled trials were included. Cross-referencing and a separate search strategy for each preconception risk and intervention ensured wider study capture.

RESULTS

Maternal prepregnancy diabetic care is a significant intervention that reduces the occurrence of congenital malformations by 70% (95% Confidence Interval (CI): 59-78%) and perinatal mortality by 69% (95% CI: 47-81%). Furthermore, preconception management of epilepsy and phenylketonuria are essential and can optimize maternal, fetal and neonatal outcomes if given before conception. Ideally changes in antiepileptic drug therapy should be made at least 6 months before planned conception. Interventions specifically targeting women of reproductive age suffering from a psychiatric condition show that group-counseling and interventions leading to empowerment of women have reported non-significant reduction in depression (economic skill building: Mean Difference (MD) -7.53; 95% CI: -17.24, 2.18; counseling: MD-2.92; 95% CI: -13.17, 7.33).

CONCLUSION

While prevention and management of the chronic diseases like diabetes and hypertension, through counseling, and other dietary and pharmacological intervention, is important, delivering solutions to prevent and respond to women's psychological health problems are urgently needed to combat this leading cause of morbidity.

Endocrine emergencies

Several potentially fatal endocrine emergencies in relation to obstetrics and gynecology are discussed in the article. Rates of case fatality vary in different series, but range from 10% to 30%. Rapid recognition, prompt supportive care, and intervention likely maximize maternal and fetal outcomes.

Humoral hypercalcemic crisis in a pregnant woman with uterine leiomyoma

We report a case of parathyroid hormone-related protein-mediated hypercalcemic crisis in a 36-year-old pregnant woman, who was admitted to women hospital with recurrent vomiting and epigastric pain. She was diagnosed with uterine fibroid since the first month of her pregnancy, but the pregnancy had been uneventful. Serum calcium was 4.8 mmol/l, while parathyroid hormone was low. Hypercalcemia was attributed to humoral hypercalcemia associated with uterine fibroid as other causes of hypercalcemia were excluded.

PTHrP-associated hypercalcemia of pregnancy resolved after delivery: a case report

A 35-year-old oriental woman, who was 32 weeks pregnant, was hospitalized with suspected preeclampsia. Subsequently, she developed stupor and lethargia. Biochemical assessment showed severe hypercalcemia (21 mg/dl) with undetectable parathyroid hormone (PTH) and markedly elevated PTH-related peptide (PTHrP) levels (26 pmol/l, normal values <1.1 pmol/l). The patient was treated with i.v. fluid administration, which resulted in an unsatisfactory reduction in serum calcium. Therefore, a cesarean section was performed to deliver the baby. Serum calcium levels promptly normalized after delivery with undetectable PTHrP levels. She delivered a healthy infant only presenting with transient mild jaundice and slightly prolonged QT interval with serum calcium level of 7.8-8.4 mg/dl (corrected for albumin levels). In the subsequent days, the patient developed a transient 'hungry bone' syndrome (calcium 6.7 mg/dl, phosphorous 2.1 mg/dl, and PTH 100.4 pg/ml). In conclusion, this pregnant patient presented with PTHrP-associated hypercalcemia, presumably of placental origin. Delivery resulted in prompt reduction of serum calcium levels and a transient 'hungry bone' syndrome.

Hypoparathyroidism in pregnancy

Pregnancy and lactation are associated with remarkable changes in calcium homeostasis, resulting from pregnancy-induced alterations in the production, metabolism and excretion of calcium and calcitropic hormones. Therefore, the clinical course of disorders affecting the parathyroid glands during pregnancy and lactation is often atypical. As the symptoms experienced by patients with parathyroid disorders are not specific, their diagnosis during gestation and breastfeeding may be sometimes very difficult. If left untreated, parathyroid disorders may pose a significant risk to the mother and fetus associated with increased perinatal and maternal morbidity and mortality. Hypoparathyroidism is a disorder rarely observed during pregnancy, resulting in most cases from surgical thyroidectomy. In our article, we present the case of a 32-year-old female with primary hypoparathyroidism diagnosed for the first time during pregnancy. We describe in details the treatment strategies undertaken in this patient and their impact on the outcome of pregnancy and lactation.

Recurrent pancreatitis induced by hyperparathyroidism in pregnancy

Introduction

As primary hyperparathyroidism affects mainly middle-aged and elderly women, it is an infrequent finding during gestation and breastfeeding. To date, less than 200 pregnant patients with primary hyperparathyroidism diagnosed during pregnancy have been described. Like in other disorders of the parathyroid gland, the recognition of primary hyperparathyroidism during pregnancy and lactation may be difficult, as clinical symptoms are not specific, while laboratory findings may be masked by some typical pregnancy-induced changes in calcium and phosphate homeostasis. If remains untreated, the disease may result in serious clinical implications for the mother and fetus. Most authors consider surgery within the second trimester of pregnancy as the treatment of choice in this group of patients.

Case report

In our paper, we discuss the case of a 35-year-old female with a history of recurrent acute pancreatitis and recurrent abortions. As the patient declined surgery, conservative management with calcitonin was started and continued throughout the rest of pregnancy, and led to giving birth to the infant whose only health problem was transient hypocalcemia.

Conclusion

The described case shows that conservative management, if started respectively early and conducted on the basis of a patient’s condition, may effectively reduce increased perinatal and maternal morbidity and mortality in pregnant women declining surgery.

Association of parathyroid adenoma and pregnancy with preeclampsia

OBJECTIVE

Case reports have described associations between calcium metabolism disturbances and primary hyperparathyroidism with preeclampsia, suggesting parathyroid involvement in preeclampsia etiology. This study examines whether parathyroid adenoma, the main cause of hyperparathyroidism, diagnosed and treated before pregnancy is associated with preeclampsia.

DESIGN

We conducted a register-based study to assess the association between parathyroid adenoma and subsequent preeclampsia.

SETTING

Births among Sweden's general population were studied.

POPULATION

The study population included 52 women with a diagnosis of parathyroid adenoma and 519 without, all of whom had a subsequent singleton pregnancy between 1973 and 1997.

METHODS

We performed a conditional logistic regression investigating the association of parathyroid adenoma with subsequent preeclampsia in the first singleton pregnancy with adjustment for potential confounding factors.

MAIN OUTCOME MEASURE

The main outcome was a diagnosis of preeclampsia that does not include women with prior chronic hypertension. To ensure that treatment of parathyroid adenoma was completed before pregnancy, those with a diagnosis of parathyroid adenoma made less than 2 yr before delivery (and the matched comparison women) were excluded.

RESULTS

Statistically, parathyroid adenoma prior to delivery is significantly (P < 0.001) associated with preeclampsia, producing an adjusted odds ratio of 6.89 (95% confidence interval, 2.30, 20.58).

CONCLUSION

A history of parathyroid adenoma should be viewed as a risk for preeclampsia.

Hypercalcemia during pregnancy, puerperium, and lactation: review and a case report of hypercalcemic crisis after delivery due to excessive production of PTH-related protein (PTHrP) without malignancy (humoral hypercalcemia of pregnancy)

Hypercalcemia during pregnancy or after delivery is uncommon, and mostly associated with primary hyperparathyroidism (PHPT). If unrecognized, it may increase maternal and fetal morbidity. In a very few patients with PHPT, hypercalcemic crisis develops during pregnancy and particularly after delivery, since calcium transport from the mother to the fetus is abruptly disrupted. Hypercalcemia may also develop in pregnant women due to PTH-related protein (PTHrP)-producing malignant tumors (humoral hypercalcemia of malignancy). Since PTHrP is produced physiologically in fetal and maternal tissues, hypercalcemia may occasionally develop during pregnancy, puerperium, and lactation due to excessive production of PTHrP in the placenta and/or mammary glands. PTHrP may also be involved in milk-alkali syndrome that develops during pregnancy. Although non-malignant hypercalcemia is usually mild, we report a 28-years-old pregnant woman who developed hypercalcemic crisis after normal delivery of an infant. On the first postpartum day, the corrected serum calcium concentration increased to 19.4 mg/dl with a markedly increased serum level of PTHrP (28.4 pmol/L) (normal <1.1 pmol/L). After administration of saline and pamidronate, the serum levels of calcium and PTHrP rapidly normalized. Extensive examination revealed no malignant lesion, suggesting that the placenta may have been producing an excessive amount of PTHrP (humoral hypercalcemia of pregnancy). We review case reports of non-malignant hypercalcemic crisis associated with pregnancy indexed in PubMed in which serum levels of intact PTH and/or PTHrP were described, and stress that rapid control of hypercalcemia is mandatory to save the life of the mother and the infant.

Maternal hypercalcemia as a possible cause of unexplained fetal polyhydramnion: a case series

OBJECTIVE

This study was undertaken to present a possible association between maternal hypercalcemia and fetal polyhydramnion.

STUDY DESIGN

Five cases of maternal hypercalcemia were diagnosed with otherwise unexplained fetal polyhydramnion. Cases are outlined; maternal and fetal/neonatal investigation, treatment, and outcome are presented.

RESULTS

Fetal polyhydramnion was identified sonographically (mean amniotic fluid index = 32 +/- 11.3 cm). Maternal hypercalcemia (mean 12.8 +/- 1.1 mg/dL) led to the diagnosis of primary hyperparathyroidism. Of the 5 women, 4 underwent parathyroidectomy. One had a hypercalcemic crisis and intrauterine fetal demise. Neonatal hypercalcemia of remaining infants was documented (mean 13 +/- 1 mg/dL), with subsequent hypocalcemia in 1 of the neonates. All mothers and the 4 live neonates were discharged in good condition.

CONCLUSION

We suggest that fetuses exposed to a hypercalcemic environment may have polyuria develop similar to adult hypercalcemic polyuria, leading to fetal polyhydramnion. Maternal serum calcium levels may be part of the investigation in otherwise unexplained polyhydramnion, as maternal hypercalcemia may threaten the health of both mother and fetus.

Malignant Hypercalcemia in Pregnancy

BACKGROUND

Hypercalcemia in pregnancy can have devastating effects on both mother and fetus. Pamidronate, a bisphosphonate and inhibitor of bone resorption, has been used to treat hypercalcemia, but it is considered contraindicated in pregnancy.

CASE

A 40-year-old multigravida presented at 24 weeks of gestation with metastatic breast cancer. After unsuccessful chemotherapy, at 28 weeks of gestation she had deteriorating renal function, frequent contractions, and a calcium level of 17.6 mg/dL. When conventional treatment of hypercalcemia failed, pamidronate dramatically decreased both the calcium levels and the frequency of uterine contractions.

CONCLUSION

Pamidronate in pregnancy successfully reduced severe maternal hypercalcemia and uterine contractions. Although the reduction in calcium level did not prevent the development of preeclampsia or further deterioration in the mother's condition, it was not associated with any adverse effects on the neonate.

Thyroid disease and other endocrine disorders in pregnancy

Endocrine disorders, in particular, thyroid disorders, are common in pregnancy. The endocrine adaptation to pregnancy, need for adequate iodine supplementation, and thyroxine replacement are presented. In addition, autoimmune diseases of the thyroid and pituitary that may occur subsequent to the immune changes of pregnancy and the postpartum period are discussed. A brief account of the presentation of other endocrine disorders (ie, pituitary,parathyroid, calcium, adrenal and gonadal disorders) also is given, along with their evaluation and management.

Micronutrients and the bone mineral content of the mother, fetus and newborn

The fluxes of the primary bone-forming minerals, calcium, phosphorus, magnesium and zinc, across the placenta and through breast milk place considerable demands on maternal mineral economy. Increases in food consumption, elevated gastrointestinal absorption, decreased mineral excretion and mobilization of tissue stores are several possible biological strategies for meeting these extra mineral requirements. This paper presents a review of the evidence on the extent to which these strategies apply in the human situation, the mechanisms by which they occur, the limitations imposed by maternal diet and vitamin D status and the possible consequences for the growth of the infant and bone health of the mother. On the strength of current evidence it appears that pregnancy and lactation are associated with physiological adaptive changes in mineral metabolism that are independent of maternal mineral supply within the range of normal dietary intakes. These processes provide the minerals necessary for fetal growth and breast milk production without requiring an increase in maternal dietary intake or compromising maternal bone health in the long term. This may not apply to pregnant women whose mineral intakes or sunlight exposure are marginal. As a vehicle for promoting optimal growth and bone mineral content of infants, supplementation of lactating women with minerals or vitamin D is unlikely to prove effective. The situation in pregnancy is less certain. Until more studies have been conducted, a precautionary case can be made for targeted supplementation of pregnant women who have very low intakes of calcium or who are at risk of vitamin D deficiency.

Primary hyperparathyroidism, hypercalcemic crisis and subsequent seizures occurring during pregnancy: a case report

A first-trimester primigravid patient presented with hyperemesis and malaise. Work-up was consistent with primary hyperparathryoidism. During acute treatment, she developed generalized motor seizures considered to be secondary to hypercalcemia. Evaluation and treatment of women with primary hyperparathyroidism and hypercalcemia are reviewed, and the pathogenesis of seizures associated with hypercalcemia is discussed.

Calcium in pregnancy and lactation

Pregnancy and lactation are periods of high calcium requirement. This review highlights recent advances in our understanding of calcium and bone metabolism during human pregnancy and lactation and discusses the findings in relation to the calcium nutrition of the mother. The evidence indicates that pregnancy and lactation are characterized by physiological adaptive processes that are independent of maternal calcium intake and that provide the calcium necessary for fetal growth and breast-milk production without requiring an increase in maternal calcium intake. There are firm data that demonstrate that a low calcium intake during lactation does not lead to impaired lactational performance or to exaggerated bone loss. However, more research is required to define whether a low calcium intake prior to or during pregnancy can have deleterious effects on reproductive and lactational performance, and on the long-term health of the mother and child.