Influence of alpha-thalassemia trait on the prevalence and severity of anemia in pregnancy among women in Kuwait

alpha -Thalassemia is very common in the Kuwaiti population, but its influe nce on anemia of pregnancy has not been previously investigated. We have sc reened a group of 59 anemic (Hb <11 g/dl) pregnant women for the <alpha>-th al-2 (-alpha -3.7 kb) deletion which is the commonest alpha -thal allele in this community, using a polymerase chain reaction method. A control group of 35 nonanemic (Hb greater than or equal to 11 g/dl) pregnant women was st udied for comparison. All the women were in the second or third trimester o f pregnancy. Among the 94 women in both groups, 69 (73.4%) had a normal com plement of alpha -globin genes (alpha alpha/alpha alpha), 18 (19.1%) were h eterozygotes (-alpha/alpha alpha) and 7 (7.4%) were homozygotes (-alpha/-al pha) giving an allele frequency of 17.0%. Among the anemic group, there wer e 44 (74.6%) individuals with a normal genotype, 9 (15.3%) heterozygotes an d 6 (10.2%) homozygotes. In the nonanemic group, the corresponding prevalen ce figures were 25 (71.4%), 9 (25.7%) and 1 (2.9%), respectively. The diffe rence between these distributions was statistically significant (chi (2) = 37.5, p < 0.0001). However, the mean Hb values were similar in heterozygote s, homozygotes and normal individuals. We, therefore, conclude that while t he <alpha>-thal trait affects the prevalence of anemia among pregnant Kuwai ti women, it does not affect its severity. Copyright (C) 2001 S. Karger AG, Basel.