Table 1

Descriptive statistics of women with RA included in the PreCARA cohort (N=171), PARA cohort (N=249) and the general population cohort (N=32 532*)

VariablePreCARA cohortPARA cohortGeneral populationP value
Maternal age at delivery (years), mean (SD)31.7±3.932.8±3.8Unavailable0.050
Disease duration at inclusion (years), median (IQR)6.5 (3.2–10.7)4.9 (2.2–9.8)n/a0.032
DAS28-CRP, third trimester, mean (SD)2.2±0.73.4±1.1n/a<0.001
DAS28-CRP, 12 weeks post partum, mean (SD)2.2+0.83.6±1.2n/a<0.001
HAQ, third trimester, median (IQR)0.50 (0.13–0.88)0.75 (0.25–1.25)n/a<0.001
Nulliparity76 (44.4)124 (51.5)5412 (48)0.153
RF and/or ACPA positive151 (88.3)186 (74.7)n/a<0.001
Presence of erosions54 (31.6)150 (60.2)n/a<0.001
Birth weight (g), mean (SD)3217±5503324±594Unavailable0.063
 Birth weight <2500 g15 (8.8)23 (9.2)602 (5)0.888
Preterm delivery (gestational age <37 weeks)19 (11.1)28 (11.2)692 (6)0.975
Education level (years), median (IQR)16 (14–18)15 (13–17)Unavailable0.001
Smoking6 (3.5)22 (8.8)Unavailable0.032
Medication post partum††
 Methotrexate44 (25.7)104 (41.8)n/a<0.001
 Prednisone69 (40.4)107 (43.0)n/a0.596
 Hydroxychloroquine93 (54.5)24 (9.6)n/a<0.001
 Sulfasalazine101 (59.1)87 (34.9)n/a<0.001
 TNF inhibitors‡‡80 (46.8)33 (13.3)n/a<0.001
 Tocilizumab9 (5.3)0 (0.0)n/a<0.001
 Golimumab1 (0.6)0 (0.0)n/a<0.001
 Abatacept2 (1.2)0 (0.0)n/a<0.001
 Azathioprine3 (1.8)4 (1.6%)n/a0.876
 Leflunomide3 (1.8)3 (1.2)n/a0.613
  • Values are numbers (%) unless indicated otherwise.

  • *Not all 32 532 participants were available at each time point.

  • †Any use during 6 months after delivery, either alone or in combination.

  • ‡Certolizumab pegol, etanercept, adalimumab or infliximab.

  • ACPA, anticitrullinated protein antibody; DAS28-CRP, 28-joint count Disease Activity Score using C reactive protein levels; HAQ, Health Assessment Questionnaire; PARA, Pregnancy-iinduced Amelioration of Rheumatoid Arthritis; PreCARA, Preconceptional Counselling in Active Rheumatoid Arthritis; RA, rheumatoid arthritis; RF, rheumatoid factor; TNF, tumour necrosis factor.