Although successful pregnancy is not an uncommon outcome in patients with homozygous beta thalassemia over the last 20 years, most of these have been reported in case reports and small series, while many publications do not appear to distinguish between pregnancies in thalassemia intermedia and those in thalassemia major. For example, of the total of 150 pregnancies in women with thalassemia reported in the literature from 1984 to 2004, 74 pregnancies appear clearly to be documented in patients with thalassemia major, while in the other 76, a reportedly late onset of transfusions suggests a milder phenotype of thalassemia intermedia. We examined the records of all thalassemia patients managed at the Toronto General Hospital, Canada (n = 82 patients with thalassemia major; 23 patients with thalassemia intermedia; 7 patients with hemoglobin E thalassemia = 112 patients over 18 years, of whom 54 are female) to determine the incidence and complications of pregnancy in our population. A surprisingly high number (17) and proportion (31%) of all female thalassemia patients over age 18 years have attempted to become pregnant. A total of 14 (82% of those who attempted pregnancy) of patients (9 thalassemia major; 4 thalassemia intermedia; 1 Hemoglobin E thalassemia) successfully conceived 26 times. The maternal age at first attempt to become pregnant was 29.6 ± 4.9 (range 18–37) years; average age at delivery was 27.2 ± 4.1 (range 19–33) years. Of the 26 conceptions, 20 were carried to term; 19 live births resulted. Six abortions and one fetal death occurred. Deferoxamine was avoided in all patients during pregnancy; control of body iron was followed using hepatic iron concentration. Pre-pregnancy hepatic iron concentration, obtained 2.8 ± 1.8 (range 1–7) years prior to conception, was 9.3 ± 7.9 (range 0.9–31) mg/gram dry weight; post partum hepatic iron concentration, obtained 3 ± 3.2 (range 0.2–10) years following parturition, was 17.4 ± 9.6 (range 1.25–32.5) mg/gram dry weight. There were one reported significant worsening in cardiac function during pregnancy; diabetes (present in one woman prior to pregnancy) developed in another woman during pregnancy. Other complications occurring or worsening during pregnancy included immune thrombocytopenic purpura and post- transfusional thrombocytopenia. In 13 of the 58 men in this population, 13 (8 with thalassemia major; 4 with thalassemia intermedia and one with Hemoglobin E thalassemia) fathered 20 children at 33.5 ± 4.8 (range 24–44) years. These data report the largest North American series of pregnancy in thalassemics and their partners and while raising issues of the safety of pregnancy in thalassemic women offer encouragement to those patients managed with adequate control of body iron burden.

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