Table 4 Characteristics associated with uncomplicated pregnancy in women with obesity but no other early pregnancy complicating factors
All women | Uncomplicated pregnancy (n = 21,776) | Complicated pregnancy (n = 16,279) | Crude RRa (95% CI) | Adjusted RRa (95% CI) | |||
|---|---|---|---|---|---|---|---|
N | Mean / n | SD / % | n | % | |||
Maternal age (years) | |||||||
Mean (SD) | 81,014 | 30·1 | 5·1 | 35·0 | 4·9 | NA | NA |
/1-year increase | NA | NA | NA | NA | NA | 0·99 (0·98–0.99) | 0·99 (0·98–0·99) |
Pre-pregnancy BMI | |||||||
Mean (SD) | 81,014 | 30·9 | 5·1 | 35·6 | 5·1 | NA | NA |
/unit increase in log (BMI) | NA | NA | NA | NA | NA | 0·32 (0·29–0·36) | 0·31 (0·27–0·34) |
PAPP-A (MoM) | |||||||
≥ 0·3 | 37,116 | 21,332 | 57·5% | 15,784 | 42·5% | Reference | Reference |
< 0·3 | 939 | 444 | 47·3% | 495 | 52·7% | 0.82 (0.77–0.88) | 0.82 (0.77–0.88) |
Missing | 42,959 | 25,446 | 59·2% | 17,513 | 40·8% | 1·03 (1·02–1·04) | 1·00 (0·99–1·02) |
Neighbourhood income level | |||||||
Quintile 1 (lowest) | 20,844 | 12,208 | 58·6% | 8636 | 41·4% | 1·00 (0·98–1·02) | 0·98 (0·96–0·998) |
Quintile 2 | 16,193 | 9316 | 57·5% | 6877 | 42·5% | 0·98 (0·96–0·999) | 0·97 (0·96–0·99) |
Quintile 3 | 16,390 | 9615 | 58·7% | 6775 | 41·3% | Reference | Reference |
Quintile 4 | 17,675 | 10,275 | 58·1% | 7400 | 41·9% | 0·99 (0·97–1·01) | 1·00 (0·98–1·02) |
Quintile 5 (highest) | 9912 | 5808 | 58·6% | 4104 | 41·4% | 1.00 (0.98–1.02) | 1·01 (0·99–1·04) |
Parity | |||||||
Nulliparous | 31,380 | 17,738 | 56·5% | 13,642 | 43·5% | Reference | Reference |
Multiparous | 49,634 | 29,484 | 59·4% | 20,150 | 40·6% | 1·05 (1·04–1·06) | 1·09 (1·07–1·10) |
Ethnicity | |||||||
Caucasian | 35,513 | 20,665 | 58·2% | 14,848 | 41·8% | Reference | Reference |
Asian | 6006 | 3103 | 51·7% | 2903 | 48·3% | 0·89 (0·87–0·91) | 0·88 (0·85–0·90) |
Black | 4676 | 2850 | 60·9% | 1826 | 39·1% | 1·05 (1·02–1·07) | 1·03 (1·01–1·06) |
Other | 3107 | 1705 | 54·9% | 1402 | 45·1% | 0·94 (0·91–0·98) | 0·93 (0·90–0·96) |
Unknown | 31,712 | 18,899 | 59·6% | 12,813 | 40·4% | 1·02 (1·01–1·04) | 0.99 (0.98–1.01) |
Conception type | |||||||
In-vitro fertilization | 1254 | 570 | 45·5% | 684 | 54·5% | 0·77 (0·73–0·82) | 0·85 (0·80–0·90) |
Intrauterine insemination | 2027 | 1022 | 50·4% | 1005 | 49·6% | 0·86 (0·82–0·90) | 0·92 (0·88–0·96) |
Spontaneous | 77,733 | 45,630 | 58·7% | 32,103 | 41·3% | Reference | Reference |