Dear Editor,

We wants to share ideas on the publication “A potential marker for predicting poor ovarian reserve (POR) in the infertile women⁽¹⁾.” To determine the association between the level of serum copeptin and the presence of POR in infertile women, Görkem and Yıldırım⁽¹⁾ conducted their research. According to Görkem and Yıldırım⁽¹⁾, this investigation verified that the infertile women with POR had a higher blood copeptin concentration and that copeptin may have a predictive value for developing POR. To elucidate the potential impacts of copeptin in the POR pathogenesis, future large-scale prospective investigations are necessary⁽¹⁾. We both agree that copeptin may be effective for ovarian reserve prediction. But it’s important to be aware of any confounding factors. The interpretation needs to be careful in areas where hemoglobinopathy is prevalent. High levels of copeptin have been linked to thalassemia⁽²⁾.