Ultrasound Assessment of Thyroid Volume in Pregnancy in the Niger Delta Region of Nigeria

Background: During normal pregnancy, the size of the thyroid gland and hormone production increase. There is increased thyroid stimulation in pregnancy, which leads to an increase in the size of the thyroid gland.

Objectives: To determine changes in thyroid volume (TV) in pregnancy and relationship with maternal age, parity, GA, weight, height and body mass index (BMI).

Subjects and Methods: This was a descriptive, cross‐sectional study which was conducted at four health facilities in Bayelsa State, Nigeria, between November, 2022 and May, 2023. Statistical Product and Service Solutions for Windows® version 25, SPSS Inc.; Chicago, USA was used for data analysis. Descriptive statistics (mean, standard deviation, frequency, and percentages) were reported. Pearson correlation coefficient was used to determine the relationship between thyroid dimensions and volume and age, parity, GA, height, weight, and BMI. Statistical significance was set at P value <0.05.

Results: Thyroid volume increased significantly (p=0.001) with GA, with a mean TV of 3.80 ± 0.00 cm3 at 20 weeks’ GA and 7.75 ± 3.01 cm3 at 40 weeks. Mean TV also showed significant positive correlations with maternal age (ɼ=0.15; p=0.003), parity (ɼ=0.42; p=0.009), weight (ɼ = 0.47; p=0.001) and BMI (ɼ = 0.38; p=0.001). Maternal height had no effect on TV (ɼ=0.08; p=0.143).

Conclusion: Our study revealed significant positive correlations between TV and maternal age, parity, GA, weight and BMI in normal pregnancy.