Characteristics of the studies participants
| Baseline characteristics of participants | Sample size | Age mean±SD (year) | BMI mean±SD | |||
| Metformin | Control | Metformin | Control | Metformin | Control | |
| Coetzee and Jackson45 | 20 | 89 | – | – | – | – |
| Hellmuth et al46 | 7 | 18 | – | – | – | – |
| Jakubowicz et al47 | 65 | 31 | 29.5±3.7 | 30.0±3.2 | 27.1±1.7 | 26.9±0.4 |
| Palomba et al43 | 31 | 16 | 26.4±2.9 | 25.9±2.7 | 27.0±2.9 | 26.7±2.8 |
| Moll et al44 | 111 | 114 | 27.9±3.7 | 28.4±4.7 | 28.5±7.1 | 27.8±6.7 |
| Hameed et al48 | 31 | 26 | 30.2±3.87 | 28.1±4.35 | 29.22±2.31 | 28.35±1.97 |
| Panchaud et al35 | 392 | 431 | 35 (31–39)* | 35 (31–38) | BMI† ≤30: 126 (28%) BMI >30: 106 (23%) | BMI† ≤30: 152 (32%) BMI >30: 17 (4%) |
| Diav-Citrin et al31 | 170‡ | 623‡ | PGDM: 36.4±5.4 | 32.0±5.2 | PGDM§: 31 (27-35) | 23 (21–29)§ |
| PCOS: 30.9±4.9 | 31.0±4.8 | PCOS§: 29 (24-37) | 23 (21–29)§ | |||
| Scherneck et al29 | 336¶ | 1011¶ | 23 (21–29)§ | 32 (28–35)§ | 29.4 (23.3–35.5)§ | 29.2 (23.8–35.4)§ |
| Kelty et al49 | 108** | 108** | ||||
| Lin et al50 †† | 626 | 222 | 33.51±4.31 | 34.48±4.02 | ||
*The mean of age (IQR) is for all metformin group including all indication (n=458).
†Number (percentage) is for all metformin group including all indication (n=458). 49% and 65% missing in metformin and control group, respectively.
‡For treatment group 119 PGDM and 51 PCOS. Control groups: 93 for PGDM; 530 for PCOS.
§Median (IQR).
¶All indication (PGDM and PCOS and other).
**Number of babies.
††Live birth: 609 and 214 in metformin and control group, respectively.
BMI, body mass index; PCOS, polycystic ovary syndrome; PGDM, pregestational diabetes mellitus.