Journal of Endocrinology and Metabolism, ISSN 1923-2861 print, 1923-287X online, Open Access |
Article copyright, the authors; Journal compilation copyright, J Endocrinol Metab and Elmer Press Inc |
Journal website http://www.jofem.org |
Original Article
Volume 8, Number 6, December 2018, pages 139-143
Iron Supplementation in Non-Anemic Pregnancy and Risk of Developing Gestational Diabetes Mellitus
Tables
Characteristics | Early iron group (n = 966) | Control group (n = 969) | P-value |
---|---|---|---|
n (%) or mean ± SD | n (%) or mean ± SD | ||
A P-value < 0.05 indicates statistical significance. BMI: body mass index; GDM: gestational diabetes mellitus; SD: standard deviation. | |||
Age (years) | 28.5 ± 5.6 | 26.4 ± 6.5 | < 0.001 |
Maternal age ≥ 30 years | 415 (43.0) | 321 (33.1) | < 0.001 |
Gravidity | 0.871 | ||
1 | 385 (39.7) | 370 (38.2) | |
2 | 384 (39.8) | 394 (40.7) | |
3 | 145 (15.0) | 148 (15.3) | |
4 or more | 54 (5.5) | 57 (5.8) | |
BMI (kg/m2) | 22.8 ± 4.3 | 23.4 ± 4.3 | 0.002 |
Pre-pregnancy BMI > 25 kg/m2 | 230 (23.8) | 288 (29.7) | 0.003 |
First booking hemoglobin (g/dL) | 12.3 ± 1.2 | 12.3 ± 0.8 | 0.308 |
First booking hemoglobin ≥ 13 g/dL | 219 (22.7) | 208 (21.5) | 0.547 |
Previous GDM | 0 (0.0) | 1 (0.1) | 1.000 |
Previous infant birth weight > 4 kg | 9 (0.9) | 10 (1.0) | 1.000 |
Previous unexplained infant death | 0 (0.0) | 2 (0.2) | 0.500 |
Family history of diabetes | 133 (13.8) | 91 (9.4) | 0.003 |
Drug adherence ≥ 75% | 689 (71.4) | 668 (68.9) | 0.253 |
Early iron group (n = 966) | Control group (n = 969) | P-value | |
---|---|---|---|
n (%) | n (%) | ||
A P-value < 0.05 indicates statistical significance. A1: subtype of gestational diabetes mellitus which does not require anti-hyperglycemic drug; A2: subtype of gestational diabetes mellitus which requires anti-hyperglycemic drug. | |||
Gestational diabetes mellitus | < 0.001 | ||
Type A1 | 75 (7.8) | 35 (3.6) | |
Type A2 | 19 (2.0) | 19 (2.0) |
Binomial regression | Multinomial regression | |
---|---|---|
RR (95% CI); P-value | RR (95% CI); P-value | |
A P-value < 0.05 indicates statistical significance. aType A1 compared to no gestational diabetes mellitus. bType A2 compared to no gestational diabetes mellitus. Factor 1: maternal age, pre-pregnancy BMI, history of DM in first-degree relatives; Factor 2: maternal age ≥ 30 years, pre-pregnancy BMI ≥ 25 kg/m2, history of DM in first-degree relatives; Factor 3: maternal age ≥ 30 years, pre-pregnancy BMI ≥ 25 kg/m2, history of DM in first-degree relatives, previous GDM, previous infant birth weight > 4 kg; Factor 4: maternal age ≥ 30 years, pre-pregnancy BMI ≥ 25 kg/m2, history of DM in first-degree relatives, previous GDM, previous infant birth weight > 4 kg, drug adherence, first hemoglobin level result. BMI: body mass index; CI: confidence interval; DM: diabetes mellitus; GDM: gestational diabetes mellitus; RR: relative risk. | ||
Univariable analysis | 1.83 (1.29, 2.59); 0.001 | 2.25 (1.49, 3.39); < 0.001a 1.05 (0.55, 2.00); 0.883b |
Multivariable analysis adjusted for | ||
Factor 1 | 1.65 (1.15, 2.39); 0.007 | 1.98 (1.29, 3.03); 0.002a |
Factor 2 | 1.68 (1.17, 2.41); 0.005 | 2.01 (1.32, 3.06); 0.001a |
Factor 3 | 1.57 (1.10, 2.25); 0.014 | 2.00 (1.31, 3.05); 0.001a |
Factor 4 | 1.56 (1.09, 2.24); 0.016 | 1.98 (1.29, 3.02); 0.002a |
Early iron group (n = 966) | Control group (n = 969) | P-value | |
---|---|---|---|
n (%) or mean ± SD | n (%) or mean ± SD | ||
A P-value < 0.05 indicates statistical significance. aHemoglobin level < 11 g/dL. SD: standard deviation. | |||
Gestational age at birth | 38.3 ± 1.4 | 38.3 ± 1.4 | 0.962 |
Infant birth weight (g) | 3,134.8 ± 431.7 | 3,096.6 ± 436.2 | 0.053 |
Maternal hemoglobin level at delivery (g/dL) | 12.4 ± 1.2 | 12.3 ± 1.1 | 0.521 |
Maternal anemia at deliverya | 48 (12.0) | 40 (11.1) | 0.734 |