Changes in hemoglobin F levels in pregnant women unaffected by clinical fetomaternal hemorrhage

Abstract

Complete automation of high-performance liquid chromatography (HPLC) for determination of hemoglobin F (%Hb F) and hemoglobin A1c (%Hb A1c) levels has made this procedure available in many clinical laboratories. However, the physiological changes in %Hb F during pregnancy and the effects of physiological and supraphysiological levels of %Hb A1c on measurement of %Hb F have not been studied extensively. Simultaneous determination of %Hb F and %Hb A1c was conducted in 490 blood samples obtained before (n = 21), during 1 st (n = 150), 2 nd (n = 116), and 3 rd (n = 192) trimesters of pregnancy, and postpartum (n = 11) from 357 women, including 60 women with hyperglycemia but unaffected by clinical fetomaternal hemorrhage, by HPLC. Mean (SD) Hb F levels were 0.71% (0.25%) before pregnancy. The value of 0.82% (0.47%) during 1 st trimester decreased significantly to 0.66% (0.35%) during 2 nd trimester and to 0.58% (0.38%) during 3 rd trimester. The level was 0.62% (0.31%) approximately one year after delivery. Thus, %Hb F was highest during 1 st trimester of pregnancy. The effects of varied %Hb A1c levels on %Hb F measurements were clinically negligible. Our data may be used as reference intervals of %Hb F determined with HPLC during pregnancy.

Haemoglobin F, A2, and S levels in subjects with or without sickle cell trait in south-eastern Gabon

“…Our study showed higher HbF levels in women, but the difference was not significant, similar to a study by Chang et al [11] Multivariate analysis showed that risk factors, such as age and sex, have a generally weak effect relative to genetic determinants. The HbF level in non-pregnant women in our study and in those in a Japanese study was similar, despite genetic differences between these two populations, confirming a standard level of 0.7% among non-pregnant women [12]. The pregnant women in our study were probably mostly in the 3rd trimester, based on the Japanese study.…”

“…No association was found in our study between HbF and sex or pregnancy, whereas other studies have shown the opposite [11,12]. Our study showed higher HbF levels in women, but the difference was not significant, similar to a study by Chang et al [11] Multivariate analysis showed that risk factors, such as age and sex, have a generally weak effect relative to genetic determinants.…”

“…The pregnant women in our study were probably mostly in the 3rd trimester, based on the Japanese study. The lack of association in our study may be due to the small sample size of pregnant women, as the mean values were similar to those reported in the Japanese study [12].…”

Single Nucleotide Polymorphisms in XMN1-HBG2, HBS1L-MYB, and BCL11A and Their Relation to High Fetal Hemoglobin Levels That Alleviate Anemia

“…The presence of SNPs may have implications in a disease, such as increased HbF levels in common and complex diseases or conditions, e.g., drug-induced conditions, SCD, β-thalassemia, anemia, diabetes, chronic kidney failure, malignancies, or obesity in many regions of the world, such as Europe, the Middle East, and Southeast Asia, including Malaysia [ 20 , 38 , 39 , 40 , 41 , 42 , 43 , 44 ]. Several SNPs, such as rs11886868, rs766432, rs9399137, rs742144, rs9399137, rs28384513, and rs4671393, are associated with erythropoiesis and HbF augmentation ( Table 1 and Figure 2 ) [ 45 , 46 , 47 ].…”

The prevalence of an elevated F cell population in a maternal and gynaecology cohort

“…The HbF level can increase when the erythropoietic process is stressed (Davis, ). As pregnancy is accompanied by an increase in the circulating blood volume of 40%, acute erythropoiesis that occurs in the first trimester may contribute to the elevation of first‐trimester HbF levels (Yamada et al, ). Normal adult erythrocytes contain 1–2% HbF.…”