Maternal characteristics and pregnancy outcomes of women with false positive early GDM (early+/late−) and true GDM (early+/late+)
| False positive early GDM (early+/late−) n=69 | True GDM (early+/late+) n=77 | P value | OR (95% CI) | |
| Maternal age (years) | 37 (19–47) | 36 (23–45) | 0.62 | |
| Prepregnancy BMI (kg/m2) | 21.8 (16.4–43.1) | 24.0 (17.3–41.8) | 0.001 | |
| Prepregnancy BMI:<18.5 kg/m2 | 8 (11.6%) | 5 (6.5%) | 0.39 | |
| Prepregnancy BMI: 18.5–25 kg/m2 | 44 (63.8%) | 38 (49.4%) | 0.096 | |
| Prepregnancy BMI:≥25 kg/m2 | 17 (24.6%) | 34 (44.2%) | 0.016 | |
| Primipara | 29 (42%) | 33 (43%) | 1.00 | |
| Smoking during pregnancy | 1 (1.4%) | 0 (0%) | ||
| Weight gain until second OGTT (kg) | 4 (−9.3–15) | 4.5 (−4.8–15.8) | 0.75 | |
| Weight gain until delivery (kg) | 8.9 (−11–19.2) | 7.7 (−5.0–18.0) | 0.25 | |
| HbA1c on baseline (%) | 5.2 (4.6–5.9) | 5.4 (4.6–6.3) | <0.001 | |
| HbA1c at second OGTT (%) | 5.1 (4.6–6.0) | 5.4 (4.8–6.1) | <0.001 | |
| HbA1c at delivery (%) | 5.5 (4.8–6.1) | 5.7 (5.0–7.5) | <0.001 | |
| Nutrition therapy (%) | Not applicable | 56 (73%) | ||
| Insulin therapy (%) | Not applicable | 21 (27%) | ||
| Hypertensive disorders of pregnancy (%) | 12 (17%) | 13 (17%) | 1.00 | |
| Birth weight (g) | 3002 (1896–3786) | 2976 (1552–4058) | 0.66 | |
| Gestational age (weeks) | 39.3 (34.0–42.1) | 38.7 (33.8–41.7) | 0.009 | |
| Preterm birth | 1 (1.4%) | 10 (12%) | 0.010 | 0.0985 (0.0122 to 0.791) |
| Macrosomia | 0 (0%) | 1 (1.3%) | ||
| Shoulder dystocia | 0 (0%) | 1 (1.3%) | ||
| Large for gestational age | 6 (8.7%) | 15 (20%) | 0.10 | 0.394 (0.143 to 1.080) |
| Cesarean delivery | 29 (42%) | 25 (32%) | 0.30 | 1.508 (0.767 to 2.963) |
| Emergency cesarean delivery | 12 (17%) | 10 (13%) | 0.49 | 1.411 (0.567 to 3.506) |
| Admission to NICU | 6 (8.7%) | 18 (23%) | 0.024 | 0.312 (0.116 to 0.840) |
| Neonatal hypoglycemia | 4 (5.8%) | 3 (3.9%) | 0.71 | 1.497 (0.323 to 6.942) |
| Neonatal hyperbilirubinemia | 7 (10%) | 11 (14%) | 0.46 | 0.667 (0.243 to 1.831) |
| Respiratory distress syndrome | 0 (0%) | 0 (0%) |
The values are expressed as mean (range) or number (%).
BMI, body mass index; GDM, gestational diabetes mellitus; HbA1c, glycated hemoglobin; NICU, neonatal intensive care unit; OGTT, oral glucose tolerance test.