Table 2.
Primary and birth outcomes
|
Placebo group |
Metformin group |
Adjusted mean difference or OR (95 % CI) | p value | |||
|---|---|---|---|---|---|---|
| Mean (SD) or n (%) | N | Mean (SD) or n (%) | N | |||
| Primary outcome | ||||||
| Z score of birthweight percentile* | 0·2680 (1·0055) | 220 | 0·2464 (1·0179) | 214 | −0·029 (−0·217 to 0·158) | 0·76 |
| Birth outcome (all births) | ||||||
| Livebirth at ≥24 weeks' gestation | 220 (99%) | 222 | 214 (97%) | 221 | .. | .. |
| Stillbirth at ≥24 weeks' gestation, miscarriage, or termination of pregnancy | 2 (1%)† | 222 | 7 (3%)‡ | 221 | 3·597 (0·739 to 17·504)§ | 0·11 |
| Birth outcome (liveborn babies at ≥24 weeks' gestation) | ||||||
| Gestational age at delivery (days) | 275·9 (15·9) | 220 | 276·6 (11·7) | 214 | .. | .. |
| Male sex | 109 (50%) | 220 | 109 (51%) | 214 | .. | .. |
| Birthweight at delivery (g) | 3463 (660) | 220 | 3462 (548) | 214 | .. | .. |
| Birthweight percentile | 57·3 (27·9) | 220 | 56·9 (28·6) | 214 | .. | .. |
OR=odds ratio.
Percentile by gestational age, sex, and parity for livebirths at ≥24 weeks' gestation.
Two terminations of pregnancy, one for fetal abnormality (split hand and foot syndrome) and one after a spontaneous membrane rupture at 18 weeks' gestation.
Of the two stillbirths, one was at 31 weeks of a baby with a known cardiac anomaly and severe hydrops fetalis and one was an intrauterine death of a normally formed baby born at 38 weeks with a birthweight less than the third percentile for gestation. Of the four miscarriages, one was after a road traffic accident and three were spontaneous. One termination of pregnancy was done after a diagnosis of trisomy 21. None of the women returned diaries nor provided a blood sample for analysis of metformin.
OR from post-hoc analysis.