The effect of thyroid function and estrogen levels on Body Mass Index in women of reproductive age

Assel Issabayeva; Aigul Durmanova; Gul; Ulpan Ibraikhanova

doi:10.1530/endoabs.90.P202

Background: Obesity in women of reproductive age has a number of negative metabolic consequences, including dyslipidemia, type 2 diabetes, cardiovascular diseases, certain types of cancer. It is associated with increased ovulatory dysfunction, complications during pregnancy, endometriosis and endocrine abnormalities, including thyroid dysfunction.

Aim: To study the prevalence of BMI and its correlation with thyroid disorders, female sex hormones and presence of endometrial hyperplasia.

Materials and methods: A single-center, retrospective, observational study included 250 women aged between 18-45 years. The anthropometric measurements, laboratory and outcomes data were compared.

Results: Additional statistical analysis included correlation matrix between several numeric variables (Table 1). Investigation the presence of association between seven numeric variables revealed six statistically significant correlations. Specifically, values of BMI negatively correlated with estradiol (r=-0.14) and T4 levels (r=-0.18). Also, a statistically significant positive correlation was detected between BMI and TSH variables (r=0.21). The strongest correlation was observed between LH and FSH levels (r=0.77). Elevation in values of LH corresponds to an increase in FSH levels. Estradiol levels possessed a low positive correlation with LH levels (r=0.16). The TSH is negatively related to T4 variable (r=-0.17). Lastly, the association between T4 and T3 levels entailed a moderate positive correlation (r=0.6). Moreover, 132 (84.08%) women with BMI >30 and 86 (95.56%) women with BMI<30.

Table 1 Correlation of BMI level with clinical/biochemical variables.
	BMI	Estradiol	LH	FSH	TSH	T4	T3
BMI	1.0000
Estradiol	-0.1383*	1.0000
LH	0.0047	0.1640*	1.0000
FSH	0.0331	-0.1180	0.7730*	1.0000
TSH	0.2053*	0.0365	-0.0725	-0.0545	1.0000
T4	-0.1847*	-0.0024	-0.0461	-0.0626	-0.1716*	1.0000
T3	0.0454	-0.0421	-0.0155	-0.0129	-0.0742	0.5987*	1.0000
BMI, body mass index; LH, luteinizing hormone; FSF, follicle-stimulating hormone; TSH, thyroid stimulating hormone; T4, free thyroxine*P<0.05

Conclusion: Obesity in women is one of the prevalent global public health problem that crucial in all stages of women’s life. Weight gain in women of reproductive age leads to a low estradiol level and, as a result, to ovulatory dysfunction, thus underweight women have an increased risk of experiencing early menopause. We suggest that the relationship between obesity, low estradiol, thyroid disorders are bidirectional. All values are three common conditions and there is an intriguing relationship between these entities, of course, further investigation is warranted in this field.

Endocrine Abstracts

P202