The Presence of Thyroid Peroxidase Antibody Is Associated with Lower Placental Weight in Maternal Thyroid Dysfunction

Abstract

Thyroid dysfunction (TD) is caused by thyroid peroxidase (TPO) antibody, as seen in Hashimoto's disease. TD is a common problem of reproductive age and may impair fetal development. Here, we determined the effect of TPO antibody on perinatal outcomes in Japanese women with TD before conception. A retrospective study involving cases of maternal TD with term singleton birth was conducted. The subjects with TD were divided into two groups according to the presence (n = 22) or absence (n = 20) of TPO antibody. The control groups matched for age, parity, and gestational weeks were selected for TPO antibody-positive (n = 44) and -negative TD subjects (n = 40), respectively. Using the standard curve of Japanese placental weight, the frequency of placental weight less than the 50th percentile (small placenta) was examined. Placental weight was lower among TPO antibody-positive TD subjects, compared with TPO antibody-negative TD subjects (p < 0.01). However, other outcomes were similar between the groups. Importantly, compared with control mothers, placental weight was significantly lower (p < 0.01), birth weight tended to be lower (p = 0.07), and the incidence of gestational diabetes mellitus was higher (p = 0.02) among TPO antibody-positive subjects. There was no significant difference in placental weight between TPO antibody-negative subjects and controls. The frequency of small placenta was significantly higher in TPO antibody-positive subjects (odds ratio: 16.7) even when considering diabetes and pregnancy induced hypertension. Thus, the presence of TPO antibody is associated with lower placental weight among Japanese women having TD.

Pregnancy Outcomes in Thyroid Cancer Survivors: A Propensity Score-Matched Cohort Study

“…maternal, infant, and placental weight gain. However, TPO-Ab may also have played a role, as recent studies have shown that placental and fetal birth weights were lower in TPO-Ab-positive subjects (18)(19)(20). Therefore, we adjusted for fT4 and TPO-Ab separately.…”

“…Initially, we thought that the changes in metabolic status caused by thyroid cancer treatment and TSH suppressive therapy altered the body’s metabolic status and reduced maternal, infant, and placental weight gain. However, TPO-Ab may also have played a role, as recent studies have shown that placental and fetal birth weights were lower in TPO-Ab-positive subjects ( 18 – 20 ). Therefore, we adjusted for fT4 and TPO-Ab separately.…”

Does thyroid autoimmunity affect the reproductive outcome in women with thyroid autoimmunity undergoing assisted reproductive technology?

“…Pregnancy women with positive TPO‐Ab had a higher prevalence of anxiety and depression than that of pregnant women without TPO‐Ab 32 . Besides, pregnant women with TPO‐Ab+ were reported to have lower placental and birthweight, and a higher incidence of gestational diabetes mellitus 33 …”

“…32 Besides, pregnant women with TPO-Ab+ were reported to have lower placental and birthweight, and a higher incidence of gestational diabetes mellitus. 33 As the incidence of TPO-Ab increases with advanced age, 15 it is speculated that the increased risk of pregnancy loss in women with TPO-Ab may be due to the confounding effect of aging. In this study, there were no significant differences in age distributions between the four study groups, and TPO-Ab + and TPO-Ab − women (30.68 ± 4.5 vs 31.34 ± 4.90, P = .323).…”

Associations between thyroid function and gestational diabetes mellitus in Chinese pregnant women: a retrospective cohort study

“…Both hypothyroidism/SCH [ 12 , 24 , 25 ] and TPO Ab-positivity [ 14 , 19 , 26 ] were suggested to be associated with a higher risk of GDM, and this risk is further increased when these statuses co-occur [ 24 , 27 ]. However, this pattern could not be supported in several other studies, as no significant associations between these factors were identified [ 14 , 17 , 18 , 20 ].…”