Screening for Anemia and Iron Deficiency in the Adult Portuguese Population
Table 2
Prevalence and prevalence ratio of anemia in nonpregnant and pregnant women stratified by age group and pregnancy trimester.
Group
Anemia
N
n
Prevalence, % (95% CI)
PR (95% CI)
Total
NPW in fertile agea
3500
1812
51.8 (50.1–53.4)
1 (reference)
Pregnant women
1125
430
38.2 (35.4–41.1)
0.74 (0.68–0.80)
1st trimester
41
11
26.8 (14.2–42.9)
0.52 (0.31–0.86)
2nd trimester
633
200
31.6 (28.0–35.4)
0.61 (0.54–0.69)
3rd trimester
451
219
48.6 (43.9–53.3)
0.94 (0.85–1.04)
18–26 years
NPW in fertile agea
870
445
51.1 (47.8–54.5)
1 (reference)
Pregnant women
203
74
36.5 (29.8–43.5)
0.71 (0.59–0.86)
1st trimester
10
0
0.0 (0.0–30.8)
-b
2nd trimester
117
33
28.2 (20.3–37.3)
0.55 (0.41–0.74)
3rd trimester
76
41
53.9 (42.1–65.5)
1.06 (0.85–1.31)
27–35 years
NPW in fertile agea
1285
634
49.3 (46.6–52.1)
1 (reference)
Pregnant women
723
281
38.9 (35.3–42.5)
0.79 (0.71–0.88)
1st trimester
23
10
43.5 (23.2–65.5)
0.88 (0.55–1.41)
2nd trimester
414
133
32.1 (27.6–36.9)
0.65 (0.56–0.76)
3rd trimester
286
138
48.3 (42.3–54.2)
0.98 (0.86–1.12)
36–44 years
NPW in fertile agea
1345
733
54.5 (51.8–57.2)
1 (reference)
Pregnant women
199
75
37.7 (30.9–44.8)
0.69 (0.58–0.83)
1st trimester
8
1
12.5 (0.3–52.7)
0.23 (0.04–1.44)
2nd trimester
102
34
33.3 (24.3–43.4)
0.61 (0.46–0.81)
3rd trimester
89
40
44.9 (34.4–55.3)
0.83 (0.65–1.04)
CI, confidence interval; N, total number of participants; n, number of participants with anemia; NPW, nonpregnant women; PR, prevalence ratio. aSubgroups of nonpregnant women matched to the same age groups of the pregnant women. bPoisson regression was not performed because the prevalence equals zero. value <0.05, value <0.01, value <0.001; Wald chi-square test.