Effect of the Cut-Off Level for Thyroid-Stimulating Hormone on the Prevalence of Subclinical Hypothyroidism among Infertile Mexican Women
Lidia Arce-Sánchez,
Salvatore Giovanni Vitale,
Claudia Montserrat Flores-Robles,
Myrna Souraye Godines-Enriquez,
Marco Noventa,
Carmen Marcela Urquia-Figueroa,
Nayeli Martínez-Cruz,
Guadalupe Estrada-Gutierrez,
Salvador Espino y Sosa,
José Romo-Yañez,
Araceli Montoya-Estrada,
Enrique Reyes-Muñoz
Affiliations
Lidia Arce-Sánchez
Department of Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Salvatore Giovanni Vitale
Unit of Gynecology and Obstetrics, Department of General Surgery and Medical Surgical Specialties, Uni versity of Catania, 95123 Catania, Italy
Claudia Montserrat Flores-Robles
Department of Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Myrna Souraye Godines-Enriquez
Deputy Director of Education in Health Sciences, National Institute of Perinatology, Ministry of Health, Mexico City 11000, Mexico
Marco Noventa
Unit of Gynecology and Obstetrics, Department of Women and Children’s Health, University of Padua, 35122 Padua, Italy
Carmen Marcela Urquia-Figueroa
Deputy Director of Education in Health Sciences, National Institute of Perinatology, Ministry of Health, Mexico City 11000, Mexico
Nayeli Martínez-Cruz
Department of Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Guadalupe Estrada-Gutierrez
Research Direction, Instituto Nacional de Perinatología, “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Salvador Espino y Sosa
Clinical Research Branch, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
José Romo-Yañez
Coordination of Gynecological and Perinatal Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Araceli Montoya-Estrada
Coordination of Gynecological and Perinatal Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
Enrique Reyes-Muñoz
Coordination of Gynecological and Perinatal Endocrinology, Instituto Nacional de Perinatología “Isidro Espinosa de los Reyes”, Montes Urales 800, Mexico City 11000, Mexico
The primary aim of this study was to compare the prevalence of subclinical hypothyroidism (SCH) using two different cut-off levels for TSH values (≥2.5 mIU/L versus ≥4.1 mIU/L). The secondary objective was to analyze the clinical-biochemical characteristics in women with and without SCH. This was a retrospective cross-sectional study. In total, 1496 Mexican women with infertility were included: Group 1, women with TSH levels ranging between 0.3 and 2.49 mIU/L, n = 886; Group 2, women with TSH between 2.5 and 4.09 mIU/L, n = 390; and Group 3, women with TSH ≥4.1 mIU/L n = 220. SCH prevalence was 40.7% (CI 95%: 38.3–43.3%) with TSH cut-off ≥ 2.5 mIU/L, and 14.7% (CI 95%: 12.7–16.5%) with TSH cut-off ≥ 4.1 mIU/L, (p = 0.0001). The prevalence of overweight was higher in Group 2 than in Groups 1 and 3. Thyroid autoimmunity, obesity and insulin resistance were higher in Group 3 than in Group 1 (p < 0.05). No other differences were observed between groups. Conclusions: The prevalence of SCH in our selected patients increased almost three times using a TSH cut-off ≥ 2.5 mIU/L compared with a TSH cut-off ≥ 4.1 mIU/L. Women with TSH ≥4.1 mIU/L compared with TSH cut-off ≤ 2.5 mIU/L more often presented with obesity, thyroid autoimmunity and insulin resistance.