Screening

Carrier screening before and during pregnancy

The American College of Obstetricians and Gynecologists recommends universal hemoglobinopathy testing for those planning pregnancy.[39][42]​​ Hemoglobin electrophoresis or molecular genetic testing should be performed when planning pregnancy, or at the initial prenatal visit if there are no previous test results available.[39]  If a woman is found to be a carrier, her reproductive partner should be offered screening.[42] Information and counseling should be offered alongside screening.[42][43]​​

Thorough genetic counseling, including a discussion of reproductive options (including preimplantation genetic testing or prenatal diagnosis) should be offered to all individuals who test positive during screening.[61][39] 

Prenatal diagnosis

Preimplantation genetic testing to prevent a pregnancy with alpha-thalassemia major is an option for prospective parents considering in vitro fertilization.[37][61]

Available tests for patients with an at-risk pregnancy include chorionic villus sampling (typically performed at 10-12 weeks' gestation in the US; 11-14 weeks' gestation in the UK) and amniocentesis (typically performed after 15 weeks' gestation).[36]​​[37][61]​​ These are invasive tests and carry a risk of fetal loss.

Ultrasound is an important noninvasive means of detecting alpha-thalassemia major in at-risk pregnancies and may reduce the need for invasive testing.​​[62][63][64]​ It is usually performed relatively late in pregnancy.​

Noninvasive prenatal testing (NIPT) of cell-free fetal DNA in maternal circulation is emerging as a prenatal screening test for hemoglobinopathies such as thalassemia and sickle cell disease.[39][65][66]​ NIPT may be considered as a screening test to detect alpha-thalassemia major, used in combination with established methods for fetal diagnosis.[16]

Newborn screening

Alpha-thalassemia is not included in the United States Recommended Uniform Screening Panel for state newborn screening programs. However, current screening methodologies used to detect sickle cell disease (reported by all states) also detect alpha-thalassemia.[35]

Asymptomatic patient with microcytosis

Screening can be performed in an asymptomatic patient with mild anemia and microcytosis to establish a diagnosis and thus avoid unnecessary and perhaps even harmful iron supplementation.

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