Pregnancy Outcomes among Women with Graves' Hyperthyroidism: A Retrospective Cohort Study

Screening and management of major endocrinopathies during pregnancy: an update

Endocrinopathies during pregnancy constitute a challenging issue, being prevalent and requiring appropriate management to avoid maternal and fetal complications. This review aims to summarize and present major endocrine problems during pregnancy, the appropriate screening, maternal monitoring and management, fetal monitoring, and follow-up. Glucose metabolism, thyroid function, as well as calcium and vitamin D metabolism are the main endocrine domains that should be screened and monitored during pregnancy. Gestational diabetes mellitus (GDM) is the most prevalent endocrine disease during pregnancy, followed by thyroid disorders. Specific recommendations are provided for the optimal clinical care of pregnant women and their offspring for GDM, thyroid disorders, and calcium and vitamin D disorders.

Associations between hyperthyroidism and adverse obstetric and neonatal outcomes: A study of a population database including almost 17,000 women with hyperthyroidism

OBJECTIVE

Large population-based studies on maternal hyperthyroidism's effect on antepartum, intrapartum, and neonatal complications are few. Most of these studies were small or did not evaluate a broad scope of possible complications. Therefore, a large population-based cohort study was conducted to study the associations between maternal hyperthyroidism and pregnancy and perinatal complications.

DESIGN

This is a retrospective population-based cohort study utilizing data from the Healthcare Cost and Utilization Project-Nationwide Inpatient Sample over 11 years from 2004 to 2014.

PATIENTS

16,984 deliveries to women with hyperthyroidism and 9,079,804 deliveries to mothers who did not suffer of hyperthyroidism.

METHODS

A cohort of all deliveries between 2004 and 2014 inclusively was created. Within this group, all deliveries to women with hyperthyroidism were the study group (n = 16,984) and the remaining deliveries were categorized as nonhyperthyroidism births and comprised the reference group (n = 9,079,804). The main outcome measures were pregnancy and perinatal complications.

RESULTS

Maternal hyperthyroidism was associated with several pregnancy and perinatal complications, including increased risks of gestational hypertension (adjusted odds ratio [aOR]: 1.236, 95% confidence interval [CI]: 1.045-1.462, p = .013) and preeclampsia (aOR: 1.190, 95% CI: 1.006-1.408, p = .042). These patients are more likely to experience preterm premature rupture of membranes (aOR: 1.322, 95% CI: 1.007-1.735, p = .044), preterm delivery (aOR: 1.287 95% CI: 1.132-1.465, p < .001), placental previa (aOR: 1.527, 95% CI: 1.082-2.155, p = .016), and suffer from venous thromboembolism (aOR: 2.894, 95% CI: 1.293-6.475, p = .010). As for neonatal outcomes, small for gestational age and stillbirth were more likely to occur in the offspring of women with hyperthyroidism (aOR: 1.688, 95% CI: 1.437-1.984, p < .001 and aOR: 1.647, 95% CI: 1.109-2.447, p = .013, respectively).

CONCLUSIONS

Women with hyperthyroidism are more likely to experience pregnancy, delivery, and neonatal complications. We found an association between hyperthyroidism and hypertensive disorders, preterm delivery, and intrauterine fetal death.

Can Thyroid Screening in the First Trimester Improve the Prediction of Gestational Diabetes Mellitus?

This study aimed to evaluate the clinical utility of the subclinical hypothyroidism (SCH) marker, elevated thyroid-stimulating hormone (TSH) and thyroid antibodies in their ability to predict subsequent gestational diabetes mellitus (GDM). In a prospective clinical trial, 230 pregnant women were screened for thyroid function during the first trimester of pregnancy. Increased TSH levels with normal free thyroxine (fT4) were considered SCH. The titers of thyroid peroxidase antibody (anti TPO Ab) at >35 IU/mL and thyroglobulin antibody (anti Tg Ab) at >115 IU/mL were considered as antibodies present. According to the OGTT results, the number of pregnant women with GDM showed the expected growth trend, which was 19%. Two groups of pregnant women were compared, one with GDM and the other without. Increased TSH levels and the presence of thyroid antibodies showed a positive correlation with the risk of GDM. TSH levels were significantly higher in pregnant women with GDM, p = 0.027. In this study, 25.6% of pregnant women met the diagnostic criteria for autoimmune thyroiditis. Hashimoto’s thyroiditis was significantly more common in GDM patients, p < 0.001. Through multivariate logistic regression, it was demonstrated that patient age, TSH 4 IU/mL, and anti TPO Ab > 35 IU/mL are significant predictors of gestational diabetes mellitus that may improve first-trimester pregnancy screening performance, AUC: 0.711; 95% CI: 0.629−0.793.

Highlighting the trajectory from intrauterine growth restriction to future obesity

During the last decades several lines of evidence reported the association of an adverse intrauterine environment, leading to intrauterine restriction, with future disease, such as obesity and metabolic syndrome, both leading to increased cardiovascular and cancer risk. The underlying explanation for this association has firstly been expressed by the Barker's hypothesis, the "thrifty phenotype hypothesis". According to this hypothesis, a fetus facing an adverse intrauterine environment adapts to this environment through a reprogramming of its endocrine-metabolic status, during the crucial window of developmental plasticity to save energy for survival, providing less energy and nutrients to the organs that are not essential for survival. This theory evolved to the concept of the developmental origin of health and disease (DOHaD). Thus, in the setting of an adverse, f. ex. protein restricted intrauterine environment, while the energy is mainly directed to the brain, the peripheral organs, f.ex. the muscles and the liver undergo an adaptation that is expressed through insulin resistance. The adaptation at the hepatic level predisposes to future dyslipidemia, the modifications at the vascular level to endothelial damage and future hypertension and, overall, through the insulin resistance to the development of metabolic syndrome. All these adaptations are suggested to take place through epigenetic modifications of the expression of genes without change of their amino-acid sequence. The epigenetic modifications leading to future obesity and cardiovascular risk are thought to induce appetite dysregulation, promoting food intake and adipogenesis, facilitating obesity development. The epigenetic modifications may even persist into the next generation even though the subsequent generation has not been exposed to an adverse intrauterine environment, a notion defined as the "transgenerational transfer of environmental information". As a consequence, if the increased public health burden and costs of non-communicable chronic diseases such as obesity, hypertension, metabolic syndrome and type 2 diabetes have to be minimized, special attention should be laid to the healthy lifestyle habits of women of reproductive age, including healthy diet and physical activity to be established long before any pregnancy takes place in order to provide the best conditions for both somatic and mental health of future generations.