Table 3. Study Participant Birth Outcomes.
| Metformin plus insulin | Insulin plus placebo | % Unadjusted difference median, or mean (95% CI)a | |
|---|---|---|---|
| Gestational age at birth, median (IQR), wkb | 37.4 (36.1-38.6) | 37.3 (35.8-38.3) | 0.14 (−0.14 to 0.29) |
| Cesarean delivery, No. (%)c | 237/377 (63) | 236/376 (63) | 0.11 (−7.28 to 7.50) |
| Primary, no labor | 101 (43) | 108 (46) | |
| Primary, after labor | 11 (5) | 19 (8) | |
| Repeat, no labor | 51 (22) | 33 (14) | |
| Repeat, after labor | 74 (31) | 76 (32) | |
| Macrosomia as indication | 11 (5) | 21 (9) | |
| Birthweight, mean (SD), gb | 3089 (74) | 3244 (78) | −155 (−265 to −45) |
| Birthweight z score, mean (SD)b,d | 0.49 (1.12) | 0.81 (1.18) | −0.32 (−0.48 to −0.15) |
| Neonatal fat mass, mean (SD), kge | 0.46 (0.30) | 0.50 (0.24) | −0.04 (−0.09 to 0.01) |
| Infant male sex, No. (%) | 185/379 (48) | 204/375 (53) | −5.59 (−12.72 to 1.54) |
Unadjusted difference for the median is reported using the Hodges-Lehmann estimator and Moses confidence limits using PROC NPAR1WAY in SAS 9.4.
Gestational age at birth and birthweight is only reported for live births having delivery data, 376 participants in the metformin plus insulin group and 370 participants in the insulin plus placebo group.
Denominators were 377 for the metformin plus insulin group and 376 for the insulin plus placebo group. Cesarean delivery and its subcategory percentages are calculated from these denominators, and subcategory percentages may not sum to 100% due to rounding.
Birthweight z score is calculated using z score for gestational age by weeks = (birthweight – mean)/standard deviation.
Neonatal fat mass was only collected on a proportion of neonates, 227 in the metformin plus insulin group and 210 in the insulin plus placebo group. Neonatal fat mass determined by anthropometric measurements using the formula: fat mass = 0.39055(birthweight) +0.0453(flank skinfold) – 003237(length) +0.54657 and calculated on 422 (55%) neonates.