Maternal low thyroxin levels are associated with adverse pregnancy outcomes in a Chinese population.

Although thyroid dysfunction in early pregnancy may have adverse effects on pregnancy outcomes, few studies have examined the relationship between maternal low free thyroxin (FT4) levels in both first and third trimesters of pregnancy and the incidence of adverse pregnancy outcomes. We hypothesized that low FT4 levels in either first or third trimesters of pregnancy may have different effects on pregnancy outcomes. The study included 6,031 mothers who provided both first and third pregnancy serum samples for analyses of thyroid function. Adverse pregnancy outcomes, such as gestational diabetes mellitus (GDM), pregnancy-induced hypertension and preeclampsia, were diagnosed using the oral glucose tolerance test, blood pressure and urine protein test. Serum metabolites like adenosine and its analogues were identified using hydrophilic interaction liquid chromatography (HILIC)-tandem mass spectrometry (MS/MS). The incidence of hypothyroidism in pregnant women tended to increase with age and pre-pregnancy body mass index (BMI). The incidence of GDM was negatively correlated with maternal FT4 levels during early pregnancy while the incidence of preeclampsia was negatively correlated with maternal FT4 levels during late pregnancy. The incidence of pregnancy-induced hypertension was not significantly correlated with maternal FT4 levels. The women who had isolated maternal hypothyroxemia (IMH) in the third trimester of pregnancy had an increased risk of developing preeclampsia. Some metabolites like adenosine and its analogues in the serum were significantly changed in pregnant mothers with IMH. In conclusion, low FT4 levels during pregnancy are a risk factor for GDM and preeclampsia. Adenosine and its analogues may be important bridges between IMH and preeclampsia.

Serum vaspin levels and vaspin mRNA expression in subcutaneous adipose tissue in women with gestational diabetes mellitus.

OBJECTIVE: To compare serum vaspin level and mRNA and protein levels of vaspin in adipose tissue in women with gestational diabetes mellitus (GDM) and normal glucose tolerance (NGR), along with the correlation between serum vaspin level with fasting insulin (FINS), homeostasis model assessment of insulin resistance (HOMA-IR) and birth-weight. STUDY DESIGN: Thirty-seven women with GDM and 36 with NGR were enrolled. Total cholesterol (TC), triglyceride (TG), high density lipoprotein cholesterol (HDL-C), low-density lipoprotein cholesterol (LDL-C), fasting plasma glucose (FPG), FINS and vaspin levels were measured. The mRNA and protein levels were detected using RT-PCR and Western blot. Pearson correlation analysis (PCA) was performed to reveal the correlation between serum vaspin level and FINS, HOMA-IR. Spearman correlation analysis (SCA) was conducted to examine the association between serum vaspin level and birth-weight. RESULTS: HDL-C level in GDM was lower than NGR group (P<0.05), and there were no statistical differences in TC, TG, LDL-C, FPG, FINS and HOMA-IR between the two groups. Serum vaspin level, mRNA and protein expression levels of vaspin in GDM were higher than NGR group (P<0.05). Serum vaspin level was not significantly correlated with FINS and HOMA-IR, but had a positive correlation with birth-weight (P=0.023). CONCLUSION: Serum vaspin level cannot serve as an independent predictor of IR. The increased serum vaspin level and increased vaspin mRNA and protein expression in adipose tissues in GDM women indicate that vaspin may be involved in the pathogenesis of GDM, but its exact mechanism needs further study.