Objective: To analyze the effects of thalassemia minor on the incidence of amniotic fluid abnormalities and the blood loss of pregnant women during delivery based on the database.
Methods: PubMed, EMBASE, EBSCO, Web of Knowledge and Ovid databases were searched for articles on the incidence of amniotic fluid abnormalities and the amount of bleeding during delivery in pregnant women with mild thalassemia; it can also be combined with manual retrieval for literature review. The data retrieval period was from the establishment of the database to June 2022. According to the Newcastle Ottawa scale score, the quality of the six included literature was evaluated, and the Revman processing software was used for meta-analysis.
Results: The 6 included articles are all high-quality literature, including 364 cases in the case group and 689 cases in the control group. The publication years of the literature are mainly from 2013 to 2021, and they are all high-quality literature. All literature was blinded, and a total of 4 pregnancy outcomes were extracted from the 6 included literature, including oligohydramnios/oligohydramnios, postpartum hemorrhage, preterm delivery, and cesarean section. Compared to normal pregnant women, the level of postpartum bleeding in thalassemia pregnant women was significantly increased [RR = 2.40, 95% CI (1.63-3.54), P < .05], and the difference was statistically significant. Compared to normal pregnant women, thalassemia pregnant women have a significantly higher risk of developing excessive/insufficient amniotic fluid [RR = 2.71, 95% CI (2.52-2.81), P < .01], and the difference is statistically significant. Compared to normal pregnant women, pregnant women with thalassemia have a significantly higher risk of premature birth [RR = 3.02, 95% CI (1.84~4.96), P < .05], and the difference is statistically significant. Compared to normal pregnant women, the risk of cesarean section in thalassemia pregnant women is significantly increased [RR = 1.68, 95% CI (1.39-2.02), P < .05], and the difference is statistically significant.
Conclusion: Thalassemia minor can increase the incidence of amniotic fluid abnormalities and the amount of bleeding during labor. In the future, we should strengthen the health education of pregnant women, improve the understanding of the disease, avoid or reduce the impact of thalassemia on newborns, improve the pregnancy outcome, and provide a more reliable basis for clinical decision-making.However, there are still certain limitations: (1) the literature selected in the study for the past 5 years is relatively small, and they are all single center, retrospective studies, and have a small sample size, resulting in insufficient accuracy of the results of the meta-analysis; (2) Some literature lacks blind methods, which may lead to language bias and implementation bias in the results; (3) The research time is still short, and it has not been clear how different types of thalassemia affect abnormal amniotic fluid volume and postpartum bleeding.