Effects of thalassemia on pregnancy outcomes of women with gestational diabetes mellitus

Aim To explore the effect of thalassemia on pregnancy outcomes of women with gestational diabetes mellitus (GDM). Methods This retrospective study reviewed the medical records of women with GDM delivered at the Chongqing Maternal and Child Health Hospital in China between July 2017 and December 2020. The live singleton pregnancies with alpha or beta-thalassemia were identified as the thalassemia group, included alpha-thalassemia subgroup and beta-thalassemia subgroup, whereas pregnant women without thalassemia were randomly selected as the non-thalassemia group according to a control-to-case ratio of 10:1 by computerized randomization. Logistic regression analyses were used to explore the potential association between thalassemia and pregnancy outcomes. Results A total of 223 pregnant women with GDM and thalassemia were analyzed, including women with alpha-thalassemia (n = 143) and beta-thalassemia (n = 80). There were no significant differences in the incidence of adverse neonatal outcomes such as preterm birth and low-birth weight among groups. However, among pregnancy complications, significant differences were detected in the incidence of placenta increta, polyhydramnios, and postpartum anemia between the thalassemia group and the non-thalassemia group. Logistic regression results indicated that beta-thalassemia increased the risk of polyhydramnios (odds ratio [OR] = 3.95, 95% confidence interval [CI]: 1.14-13.65, p = 0.030) and chorioamnionitis (OR = 3.61, 95%CI: 1.04-12.49, p = 0.043) compared with the non-thalassemia group. Conclusion In our study, thalassemia did not increase adverse neonatal outcomes, but beta-thalassemia increased the risk of pregnancy complications, including polyhydramnios and chorioamnionitis.