A new study published in Current Medical Science suggests thyroid diseases are an independent risk factor for platelet antibody positivity in pregnant women, which increases the risk of complications, including fetal and neonatal alloimmune thrombocytopenia (FNAIT).
Researchers in China analyzed blood samples from 5,037 pregnant women admitted for delivery between June 30, 2022, and April 7, 2024, to investigate the prevalence of platelet antibodies and factors linked to their development.
Overall, 387 of the 5,037 women tested positive for platelet antibodies, representing a positivity rate of about 8%. Rates increased significantly with maternal age, rising from just over 6% in women aged 25 years or younger to 10% in those aged 36 years or older. Women with a history of blood transfusion had a markedly higher positivity rate of nearly 26% compared with about 8% in those who had never had one.
The likelihood of a positive result also increased with the number of pregnancies and miscarriages. Women with three or more pregnancies had about a 12% positivity rate, compared with 5% among those with first-time pregnancies. Those with three or more miscarriages had a positivity rate of about 15%, more than double the rate in women with no miscarriage history.
Learn more about FNAIT causes and risk factors
Among pregnancy-related diseases, thalassemia showed the highest platelet antibody positivity rate at 16%, followed by thyroid diseases at nearly 12%. Further analysis revealed substantial variation between thyroid conditions, with the highest positivity rates observed in thyroid nodules, goiters, thyroid malignancies and Hashimoto’s thyroiditis.
The researchers noted that the association between thyroid disorders and platelet antibody positivity may reflect shared autoimmune mechanisms and immune dysregulation. Given the link between platelet antibodies and complications such as miscarriage and FNAIT, the researchers stated that the findings suggest thyroid status should be considered during antenatal risk assessment.
“Consequently, proactive antibody screening is warranted for pregnant women with thyroid disorders to mitigate the associated risks of miscarriage and FNAIT,” the authors conclude.
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