Iron status in Danish women aged 35–65 years

Abstract

Iron status was assessed by serum (S‐) ferritin and hemoglobin (Hb) in a population survey comprising 883 non‐gravid Danish women in age cohorts of 35, 45. 55, and 65 years. Premenopausal women (n = 676) had lower S‐ferritin, median 42 μg/1, than postmenopausal women (n = 207), median 80 μg/1 (p<0.0001). Of premenopausal women, 12.1% had S‐ferritin ≤ 20 μg/1 (i.e. depleted iron stores), and 35.6% S‐ferritin of 21–40 μg/1 (i.e. small iron stores). Corresponding figures in postmenopausal women were 0.5%, and 13.2%. Premenopausal blood donors (n = 88) had lower S‐ferritin than non‐donors (p<0.001). In premenopausal women, S‐ferritin levels were strongly dependent on the duration of menstrual bleeding (p < 0.0001). which in turn was related to the method of contraception. Women (n = 64) using hormonal contraceptives (the pill) had menstrual bleeding of shorter duration than those (n = 511) not using pills or intrauterine devices (IUD), who in turn had bleeding of shorter duration than those (n= 101) using IUD. Median S‐ferritin in pill users was 62 μg/L in those not using pills or IUD 42 μg/L and in IUD users 36 μg/l. S‐ferritin values < 40 μg/l (i.e. small and depleted iron stores) were seen in 25%) of pill users. in 48% of those not using pills nr IUD, and in 61% of IUD users. Hb values in premenopausal women were mean 134 ± 10 (SD) g/1 (8.3±0.6 mmol/l), median 132 g/l (8.2 mmol/l). being slightly lower than in postmenopausal women, mean 137 ± 10 g/l (8.5±0.6 mmol/1), median 135 g/l (8.4 mmol/ 1) (p<0.001). Iron deficiency anemia (i.e. S‐ferritin ≤20 μg/l and Hb < 121 g/l) was found in 3.0%) of premenopausal and in none of postmenopausal women.