Table 3 The risk of perinatal complications categorized by maternal presence of polycystic ovary syndrome (PCOS) and exposure to metformin
|  | PCOS(−) Metformin(−) | PCOS(−) Metformin(+) | PCOS(+) Metformin(−) | PCOS(+) Metformin(+) | PCOS(−) Metformin(+) | PCOS(+) Metformin(−) | PCOS(+) Metformin(+) | PCOS(−) Metformin(+) | PCOS(+) Metformin(−) | PCOS(+) Metformin(+) |
|---|---|---|---|---|---|---|---|---|---|---|
Number (%) | Crude, OR (95% CI) | Adjusted, OR (95% CI)b | ||||||||
994,102 | 870 | 21,486 | 347 | Â | Â | Â | Â | Â | Â | |
Preterm birth (< 37 w)a | ||||||||||
 Yes | 43,597 (4.4) | 91 (10.53) | 1344 (6.28) | 24 (6.92) | 2.56 (2.05–3.19) | 1.46 (1.38–1.54) | 1.62 (1.07–2.44) | 0.98 (0.78–1.24) | 1.30 (1.23–1.38) | 0.87 (0.56–1.35) |
 No | 947,422 (95.6) | 773 (89.47) | 20,041 (93.72) | 323 (93.08) |  |  |  |  |  |  |
Stillbirth | ||||||||||
 Yes | 3083 (0.31) | 6 (0.69) | 101 (0.47) | 0 (0) | 2.23 (1.00–4.98) | 1.52 (1.24–1.86) | – | 0.88 (0.39–2.02) | 1.30 (1.06–1.59) | – |
 No | 991,019 (99.69) | 864 (99.31) | 21,385 (99.53) | 347 (100) |  |  |  |  |  |  |
Low birth weight (< 2500 g) | ||||||||||
 Yes | 30,385 (3.06) | 33 (3.79) | 906 (4.22) | 12 (3.46) | 1.25 (0.88–1.77) | 1.40 (1.30–1.50) | 1.14 (0.64–2.02) | 0.92 (0.65–1.31) | 1.29 (1.20–1.38) | 0.87 (0.49–1.57) |
 No | 963,717 (96.94) | 837 (96.21) | 20,580 (95.78) | 335 (96.54) |  |  |  |  |  |  |
Macrosomia (>  4000 g) | ||||||||||
 Yes | 186,133 (18.72) | 224 (25.75) | 4197 (19.53) | 78 (22.48) | 1.51 (1.29–1.76) | 1.05 (1.02–1.09) | 1.26 (0.98–1.63) | 0.75 (0.63–0.89) | 0.98 (0.94–1.02) | 0.86 (0.66–1.13) |
 No | 807,969 (81.28) | 646 (74.25) | 17,289 (80.47) | 269 (77.52) |  |  |  |  |  |  |
Apgar 5 min < 7a | ||||||||||
 Yes | 11,109 (1.12) | 16 (1.85) | 337 (1.58) | 10 (2.88) | 1.66 (1.02–2.73) | 1.41 (1.27–1.58) | 2.62 (1.40–4.91) | 0.72 (0.44–1.2) | 1.17 (1.05–1.31) | 1.37 (0.73–2.55) |
 No | 979,910 (98.88) | 848 (98.15) | 21,048 (98.42) | 337 (97.12) |  |  |  |  |  |  |
SGA | ||||||||||
 Yes | 23,152 (2.33) | 17 (1.95) | 491 (2.29) | 8 (2.31) | 0.84 (0.52–1.35) | 0.98 (0.89–1.08) | 0.99 (0.49–2.00) | 0.95 (0.58–1.54) | 0.92 (0.84–1.01) | 0.90 (0.45–1.82) |
 No | 970,950 (97.67) | 853 (98.05) | 20,995 (97.71) | 339 (97.69) |  |  |  |  |  |  |
LGA | ||||||||||
 Yes | 33,315 (3.35) | 125 (14.37) | 1000 (4.65) | 31 (8.93) | 4.84 (3.95–5.93) | 1.41 (1.31–1.51) | 2.83 (1.94–4.13) | 0.54 (0.42–0.69) | 1.11 (1.03–1.20) | 0.75 (0.45–1.25) |
 No | 960,787 (96.65) | 745 (85.63) | 20,486 (95.35) | 316 (91.07) |  |  |  |  |  |  |