Advanced Ultrasound in Diagnosis and Therapy (Mar 2018)
Ultrasonographic Assessment of Thyroid Nodules in Two Groups of Pregnant Women: Is the Nodular Phenotypic Expression Dependent on Obstetric and/or Environmental Factors?
Abstract
Objective: To evaluate the association between the obstetric and environmental factors and the phenotypic expression of thyroid nodules (TN) in two groups of women with differences in terms of race and regional localization. Methods: A retrospective study in 92 non-healthy pregnant women (51 Chinese and 41 Congolese) who consulted the endocrinology. Ultrasonographic characteristics of TN as well as thyroid hormone levels were evaluated. Results: The obstetric history was more loaded in the Congolese group than in the Chinese. The prevalence of TN was 10 times higher in Congolese women than in Chinese (odds ratio (OR) = 10.1, P < 0.001), and was correlated to the parity in the two study populations (three times higher in women with more than three births in the past (OR = 3.3, P < 0.001 vs nulliparous)). Multiple thyroid nodules (MTN) were associated with parity in the Congolese women (OR = 4.5, P = 0.04). Mean value of maximal diameter (32.8 ± 3 mm vs 7.2 ± 1 mm, P = 0.001) and that of volume (29.1 ± 4 mL vs 0.2 ± 0.1 mL, P = 0.003) of single/dominant nodules were greater in the Congolese women than in the Chinese. Most of Single/Dominant (S/D) nodules (47.1%) were anechoic in the Chinese, while heterogeneous in the Congolese group (51.4%). Conclusion: Parity plays a substantial role in the occurrence of TN. Nodular phenotypic expression may vary according to regions (or environments), and probably interaction between genetic predispositions (possibly) and other factors (as parity and iodine deficiency) could have a paramount role in controlling that phenotypic expression.
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