A1C but not serum glycated albumin is elevated in late pregnancy owing to iron deficiency.
OBJECTIVE
A1C levels have been shown to be elevated in relation to glycemia in late pregnancy, although the precise mechanisms remain undetermined. We hypothesized that iron deficiency is involved in the A1C increase in late pregnancy.


METHODS
In study 1, A1C, serum glycated albumin, erythrocyte indexes, and iron metabolism indexes were determined in 47 nondiabetic pregnant women not receiving iron supplementation who were divided into four groups according to gestational period (group I, 21-24 weeks; group II, 25-28 weeks; group III, 29-32 weeks; and group IV, 33-36 weeks). In study 2, these determinants were obtained at two gestational periods (20-23 weeks and 32-33 weeks) in 17 nondiabetic pregnant women.


RESULTS
In study 1, A1C levels were higher in groups III and IV than those in groups I and II, whereas serum glycated albumin levels were not different among these four groups. Hemoglobin, mean corpuscular hemoglobin (MCH), serum transferrin saturation, and serum ferritin were lower in groups III and IV. A1C levels were negatively correlated with MCH, serum transferrin saturation, and serum ferritin. In study 2, A1C levels were significantly increased at gestational weeks 32-33 from those at weeks 20-23, whereas serum glycated albumin levels did not differ between the two gestational periods. MCH, serum transferrin saturation, and serum ferritin were decreased at gestational weeks 32-33. A1C levels showed a negative correlation with MCH, serum transferrin saturation, and serum ferritin.


CONCLUSIONS
A1C levels were elevated in late pregnancy owing to iron deficiency. Serum glycated albumin may offer a better index for monitoring glycemic control in pregnancy.
Hashimoto
Kunihiko
K
Department of Medicine, Aizenbashi Hospital, Osaka, Japan.
Noguchi
Sanai
S
Morimoto
Yasuhiko
Y
Hamada
Shinichi
S
Wasada
Kenshi
K
Imai
Shiro
S
Murata
Yuji
Y
Kasayama
Soji
S
Koga
Masafumi
M
D000328:Adult; D018798:Anemia, Iron-Deficiency / Q000097:blood*; D016640:Diabetes, Gestational / Q000097:blood; D004912:Erythrocytes / Q000378:metabolism; D005260:Female; D006442:Glycated Hemoglobin / Q000378:metabolism*; D017127:Glycation End Products, Advanced; D006801:Humans; D008137:Longitudinal Studies; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood*; D011262:Pregnancy Trimester, Second; D011263:Pregnancy Trimester, Third; D012016:Reference Values; D012709:Serum Albumin / Q000378:metabolism*; D000093423:Glycated Serum Albumin
D006442:Glycated Hemoglobin; D017127:Glycation End Products, Advanced; D012709:Serum Albumin; D000093423:Glycated Serum Albumin