Table 2. Comparison of characteristics of women with normal glucose tolerance, impaired glucose tolerance and diabetes.
| Normal glucose tolerance (n = 250) | Impaired glucose tolerance(n = 142) | Diabetes (n = 15) | p-value | |
|---|---|---|---|---|
| Pre-pregnancy characteristics | ||||
| Age (years) | 31.6±5.5 | 32.6±6.2 | 35.6±5.8 | 0.02 |
| 95% BCa C.I. | 30.2–31.8 | 31.1–33.6 | 31.2–37.5 | 0.04 |
| parity | ||||
| primiparous | 67 (26.9) | 35 (24.8) | 2 (13.3) | 0.49 |
| multiparous | 183 (73.1) | 107 (75.2) | 13 (86.7) | |
| Family history of type 2 diabetes | ||||
| Yes | 172 (68.7) | 112 (78.7) | 13 (86.7) | 0.04 |
| Pre-pregnancy BMI | 27.4 ±5.6 | 28.3 ±5.5 | 34.3 ±5.5 | <0.01 |
| 95% BCa C.I. | 26.3–28.1 | 27.2–29.4 | 30.8–37.8 | <0.01 |
| BMI < 25 | 84 (33.6) | 43 (30.4) | 0 (0.0) | <0.01 |
| BMI 25.1–29.9 | 58 (23.2) | 33 (23.2) | 1 (6.7) | |
| BMI ≥ 30 | 108 (43.2) | 66 (46.4) | 14 (93.3) | |
| Pregnancy characteristics | ||||
| Pregnancy glucose level | ||||
| Fasting | 4.6 ± 0.69 | 4.8 ±0.64 | 5.5 ±0.77 | <0.01 |
| 95% BCa C.I. | 4.6–4.8 | 4.7–4.9 | 5.1–6.1 | <0.01 |
| I hour | 7.6 ±1.9 | 7.9 ±2.2 | 8.1 ±2.2 | 0.28 |
| 95% BCa C.I. | 7.22–7.87 | 7.37–8.61 | 8.91–10.92 | 0.16 |
| 2 hours | 6.3 ± 2.1 | 6.6 ± 2.1 | 7.6 ±2.2 | 0.04 |
| 95% BCa C.I. | 5.90–6.58 | 6.08–7.18 | 8.60–9.01 | 0.03 |
| GDM | ||||
| Yes | 58 (23.2) | 60 (42.3) | 15 (100.0) | <0.01 |
| Treatment of GDM | ||||
| Diet | 56 (96.6) | 56 (93.3) | 9 (60.0) | <0.01 |
| insulin | 2 (3.4) | 4 (6.7) | 6 (40.0) | |
| Post-pregnancy anthropometric measurements | ||||
| Current BMI (kg/m2) | ||||
| BMI (mean ±SD) | 29.3 ± 6.2 | 31.1 ± 6.6 | 36.2 ± 4.8 | 0.01 |
| 95% BCa C.I. | 28.0–29.9 | 29.7–32.2 | 33.9–39.7 | <0.01 |
| BMI< 25 | 69 (27.7) | 26 (18.4) | 0 (0.0) | <0.01 |
| BMI 25.1–29.9 | 75 (30.1) | 37 (26.2) | 2 (13.3) | |
| BMI ≥ 30 | 105 (42.2) | 78 (55.3) | 13 (86.7) | |
| WC (mean ±SD) (cm) | 82.4 ± 14.4 | 87.2 ± 13.0 | 89.2± 10.0 | <0.01 |
| 95% BCa C.I. | 76.26–79.85 | 79.76–85.67 | 87.22–94.07 | <0.01 |
| Breast feeding (at 4 months) | 110 (44.0) | 65 (45.7) | 6 (40.0) | 0.42 |
| Hormonal contraceptive use | 111 (44.4) | 53 (37.1) | 7(46.7) | 0.34 |
| Systolic Blood Pressure | 112.9±13.5 | 113.4±17.5 | 115.2±14.6 | 0.80 |
| 95% BCa C.I. | 110.61–114.99 | 108.53–116.92 | 112.85–121.90 | 0.83 |
| Diastolic blood pressure | 67.8±9.2 | 71.6±8.7 | 72.5±7.2 | 0.01 |
| 95% BCa C.I. | 66.35–69.32 | 69.41–73.45 | 73.56–75.11 | 0.03 |
95% BCa C.I., 95% Bias Corrected and accelerated Confidence Interval; GDM, Gestational diabetes; BMI, Body Mass Index; WC, Waist circumference
All women who developed type 2 diabetes had history of GDM and none of the women who were normoglycemic during pregnancy developed type 2 diabetes. The RR of all factors for development of glucose intolerance is shown in Table 3. History of GDM in the index pregnancy almost doubled the risk of developing postpartum glucose intolerance; (RR 1.91, 95% confidence intervals (C.I.) (1.31 to 2.78), P<0.01). Similarly, women with BMI ≥ 30 kg/m2, had almost double the risk of developing postpartum glucose intolerance compared to women with lower BMI, (RR 1.79, 95% C.I. (1.17–2.97), P = 0.02) (Table 3). In addition higher diastolic blood pressure increased the risk of developing diabetes and IGT (RR 1.03, 95% C.I. (1.001–1.066), P = 0.04).