{
  "abstract": "Background\n\nJanus kinase inhibitors (JAKi) are increasingly being used in the management of autoimmune diseases across rheumatology, gastroenterology, and dermatology, including in women of childbearing age. Consequently, pregnancies occurring during JAKi treatment are becoming more common. However, uncertainties regarding their safety during pregnancy remain, and current human data are insufficient to allow a comprehensive assessment of fetal risk.Methods\n\nObservational data of pregnancies with first trimester JAKi exposure, recorded in the German Embryotox database, was analyzed. Pregnancies were prospectively enrolled between January 1, 2017, and November 15, 2025. Study endpoints included major congenital anomalies, pregnancy loss, and neonatal parameters.Results\n\nThe cohort comprised a total of 44 pregnancies exposed to baricitinib (n = 17), filgotinib (n = 3), tofacitinib (n = 8), or upadacitinib (n = 16). A total of 32 live births were recorded. Among these, two major congenital anomalies were observed, one ventricular septal defect and one hypospadias. Five spontaneous abortions occurred, including one case of fetal anencephaly, and seven elective terminations of pregnancy were reported. Additional neonatal assessments revealed two preterm births at 36 weeks' gestation, three infants born small for gestational age, and two newborns large for gestational age.Conclusions\n\nThe current evidence is insufficient to establish or exclude an association between JAK inhibitor exposure and adverse fetal outcomes. To date, the potential for harmful effects cannot be ruled out due to the limited available data. Therefore, routine use of JAKi during pregnancy is not recommended and treatment should be approached with caution, and requires a critical risk-benefit assessment until further data is obtained.Trial registration\n\nThe study was retrospectively registered in the German Clinical Trials Register on March 16, 2026 (DRKS00039622).",
  "abstract_shown": true,
  "affiliations": [
    "Charité - University Medical Center Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Embryotox Center of Clinical Teratology and Drug Safety in Pregnancy, Augustenburger Platz 1, 13353, Berlin, Germany. anna.habbel@charite.de.",
    "Charité - University Medical Center Berlin, Corporate Member of Freie Universität Berlin and Humboldt-Universität zu Berlin, Institute of Clinical Pharmacology and Toxicology, Embryotox Center of Clinical Teratology and Drug Safety in Pregnancy, Augustenburger Platz 1, 13353, Berlin, Germany."
  ],
  "article_type": "research article",
  "arxiv": null,
  "author_total": 4,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Anna-Sophia Habbel"
    },
    {
      "affs": [
        1
      ],
      "name": "Evelin Beck"
    },
    {
      "affs": [
        1
      ],
      "name": "Anne Mueller"
    },
    {
      "affs": [
        1
      ],
      "name": "Katarina Dathe"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/4ggmrn2wyp89k.bib",
  "cited_by": 0,
  "doi": "10.1186/s40360-026-01263-4",
  "fulltext_url": "https://europepmc.org/articles/PMC13688848",
  "id": "4ggmrn2wyp89k",
  "issns": [
    "2050-6511"
  ],
  "landing_url": "https://europepmc.org/article/MED/42908038",
  "language": "eng",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "article",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "RA1190-1270"
    ],
    [
      "lcc",
      "RM1-950"
    ],
    [
      "openalex",
      "2739|Pregnancy and Medication Impact"
    ]
  ],
  "openalex": "W7223010251",
  "pdf_url": "https://europepmc.org/articles/PMC13688848?pdf=render",
  "pmcid": "PMC13688848",
  "pmid": "42908038",
  "published": "2026-10-20",
  "publisher": "BMC",
  "ris": "https://research.draconitic.com/paper/4ggmrn2wyp89k.ris",
  "sources": [
    {
      "first_seen": "2026-10-30T12:19:53Z",
      "native_id": "MED:42908038",
      "source": "europepmc",
      "url": "https://europepmc.org/article/MED/42908038"
    },
    {
      "first_seen": "2026-10-30T13:46:20Z",
      "native_id": "3ba17ae554d5434689f3b093363029b2",
      "source": "doaj",
      "url": "https://doi.org/10.1186/s40360-026-01263-4"
    }
  ],
  "subjects": [
    {
      "field": "medicine",
      "origin": "openalex:2739|Pregnancy and Medication Impact",
      "subfield": "epidemiology-public-health"
    }
  ],
  "title": "Pregnancy outcome after first-trimester exposure to JAK inhibitors - an evaluation of the German Embryotox cohort.",
  "title_text": "Pregnancy outcome after first-trimester exposure to JAK inhibitors - an evaluation of the German Embryotox cohort.",
  "type": "peer-reviewed",
  "updated_at": "2026-10-30T13:46:20Z",
  "url": "https://research.draconitic.com/paper/4ggmrn2wyp89k",
  "venue": "BMC pharmacology & toxicology",
  "versions": []
}