{
  "abstract": "Objective To estimate risk and to identify risk factors for preterm birth in pregnant women with psoriatic arthritis (PsA) in relation to maternal characteristics, treatment and disease activity, both before and during pregnancy.Methods We linked clinical rheumatology registers to medical birth registers in Sweden, Denmark and Norway and identified PsA pregnancies and control pregnancies 2006–2021, matched 1:10 on age, parity, country and birth year. Adjusted ORs (aORs) for preterm birth in PsA pregnancies vs control pregnancies were calculated overall and stratified by maternal characteristics, antirheumatic treatment and disease load (9 months before and during pregnancy).Results We observed 54 preterm births among 688 PsA pregnancies (7.8%) versus 312 among 6880 control pregnancies (4.5%); aOR, 95% CI: 1.80, 1.29 to 2.51. The risk estimate was largely unaffected by parity, smoking and body mass index. PsA pregnancies exposed to a combination of biologic and conventional synthetic disease-modifying antirheumatic drugs (DMARDs) and/or glucocorticoids during pregnancy had a markedly increased risk of preterm birth compared with control pregnancies (4.44, 2.07 to 9.50), whereas exposure to biological DMARD (bDMARD) monotherapy (primarily tumour necrosis factor inhibitors) had not (0.73, 0.22 to 2.42). High disease load before pregnancy was associated with increased risk. The proportion of preterm birth was higher in those stopping bDMARD during the first trimester (21%) opposed to those continuing past the first trimester (10%) based on few events.Conclusion We identified an 80% increased risk of preterm birth in PsA pregnancies compared with control pregnancies. Antirheumatic combination therapy during and high disease load before pregnancy constituted risk factors. Discontinuing bDMARD treatment in early pregnancy further increased the risk. Our findings support that a subgroup of PsA pregnancies should be considered high-risk pregnancies.",
  "authors": [
    {
      "affiliations": [
        "COPECARE (Copenhagen Center for Arthritis Research, Centre for Rheumatology and Spine Diseases), HovedOrtoCentret, Rigshospitalet, Copenhagen, Denmark",
        "Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark"
      ],
      "name": "Anne Emilie Pape Secher"
    },
    {
      "affiliations": [
        "Clinical Epidemiology Division, Department of Medicine Solna, Karolinska Institute, Stockholm, Sweden"
      ],
      "name": "Fredrik Granath"
    },
    {
      "affiliations": [
        "Clinical Epidemiology Division, Department of Medicine Solna, Karolinska Institute, Stockholm, Sweden"
      ],
      "name": "Katarina Remaeus"
    },
    {
      "affiliations": [
        "COPECARE (Copenhagen Center for Arthritis Research, Centre for Rheumatology and Spine Diseases), HovedOrtoCentret, Rigshospitalet, Copenhagen, Denmark",
        "Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark",
        "DANBIO, Rigshospitalet, Copenhagen, Denmark"
      ],
      "name": "Bente Glintborg"
    },
    {
      "affiliations": [
        "Department of Gynecology, Fertility and Obstetrics, Juliane Marie Centre, Rigshospitalet, Copenhagen, Denmark",
        "Research Unit of Gynaecology and Obstetrics, Department of Clinical Research, University of Southern Denmark, Odense, Denmark"
      ],
      "name": "Ane Lilleøre Rom"
    },
    {
      "affiliations": [
        "Center for Treatment of Rheumatic and Musculoskeletal Diseases (REMEDY), Diakonhjemmet Hospital, Oslo, Norway",
        "Research Unit, Sørlandet Sykehus HF, Kristiansand, Norway"
      ],
      "name": "Brigitte Michelsen"
    },
    {
      "affiliations": [
        "COPECARE (Copenhagen Center for Arthritis Research, Centre for Rheumatology and Spine Diseases), HovedOrtoCentret, Rigshospitalet, Copenhagen, Denmark",
        "Department of Clinical Medicine, University of Copenhagen, Copenhagen, Denmark"
      ],
      "name": "Merete Lund Hetland"
    },
    {
      "affiliations": [
        "Clinical Epidemiology Division, Department of Medicine Solna, Karolinska Institute, Stockholm, Sweden",
        "Centre for Rheumatology, Academic Specialist Center, Karolinska Institute, Stockholm, Sweden"
      ],
      "name": "Karin Hellgren"
    }
  ],
  "title": "Preterm birth in women with psoriatic arthritis: what are the risks and risk factors? A collaborative cohort study from Sweden, Denmark and Norway",
  "uid": "c16d54d1-5282-50f7-95b4-0be2e2e3fdf2"
}