Examination and Sampling of Chorionic Villi for the Diagnosis of Beta-Thalassemia Major in the First Trimester of Pregnancy in Southwestern Iran

Beta thalassemia is one of the most common hereditary diseases in Iran. The birth of a child with thalassemia causes many social and economic problems for parents and the health care system. Nowadays, prenatal screening programs to detect beta thalassemia have received much attention in the country. The aim of the present study was the determination and sampling of chorionic villi for the diagnosis of beta-thalassemia major in the first trimester of pregnancy in south-western Iran.

The present descriptive-prospective and practical study was conducted in 2021 on couples suffering from thalassemia minor and referred to the Narges Genetics Laboratory in Ahwaz, Iran. For preventive measures, blood samples were taken from volunteers. At that point, the couples who had HbA2 above 3.5 and were in the 10th to 13th week of pregnancy continued the treatment by performing chorionic villus sampling in order to evaluate the health of the fetus. Chorionic villus sampling was performed under local anesthesia with a needle from the abdominal area of pregnant women, and about 5-10 cc of placental trophoblast villi were collected. The collected data were analyzed using t-test and chi-square statistical tests.

A total of 91 pregnant women underwent chorionic villus sampling. Thirty-eight individuals (41.8%) had thalassemia minor, 25 individuals (27.5%) had thalassemia major, the familial relationship between couples was also examined, and there was no significant association between the familial relationship and occurrence of thalassemia major. 20 people (30%) had a child with thalassemia major and 60 people (66%) had a child with thalassemia minor. Fetuses with thalassemia major in mothers with blood type A+, 38 subjects (42%) and O+ 35 subjects (38.4%), the prevalence of thalassemia major was higher in the Fars subjects, the highest in 39 subjects (42.8%), and the lowest was the Kurdish people with one person (1 percent).

The technique of chorionic villus sampling is an accurate method with no significant risk to both mother and fetus. This method can be used to diagnose beta thalassemia before birth.