Table 1

Characteristics of patients (SLE) and population controls, reported as n (%) unless specified as mean (SD)

CharacteristicSLEPopulation controlsP value
Number of deliveries180498 849
Maternal age (years), mean (SD)31.5 (5.0)30.4 (5.1)0.004
 <35138 (76.7)402 064 (80.6)
 ≥3542 (23.3)96 569 (19.4)
 Missing
Parity0.91
 No children77 (42.8)209 978 (42.1)
 ≥1 child103 (57.2)288 871 (57.1)
 Missing
Smoking in pregnancy12 (6.9)47 137 (11.2)0.09
 Missing679 171
BMI first trimester, mean (SD)23.8 (4.9)24.3 (4.8)0.30
 Underweight (<18.5)7 (8.3)8298 (4.1)
 Normal weight (18.5–24.9)50 (59.5)123 903 (61.5)
 Overweight (≥25)27 (32.1)69 294 (34.4)
 Missing96297 354
  • BMI, body mass index; SLE, systemic lupus erythematosus.