{
  "abstract": "Introduction Since widespread availability of highly effective CFTRm elexacaftor/tezacaftor/ivacaftor, pregancy rates have doubled among fwCF in the UK. 1 Historically, CF-pregnancy has been high risk, and guidelines from pre-CFTRm era considered pre-conception FEV1<50% and/or pulmonary hypertension absolute contraindications,2 with lower lung function correlating with worse maternal and fetal outcomes including pre-term (<37 weeks) births.With improved female CF subfertility and general health the association of pre-conception lung function and obstetric outcomes warrants renewed investigation.Method Retrospective electronic health care records review of fwCF who completed pregnancies in a large, dedicated CF-Maternal Health Service September 2020-June 2025. Analysis of pregnancy outcomes according to pre-conception ppFEV1 impairment: Severe<50%, moderate 50–80%, mild >80%.Results There were 106 pregnancies over the time period: 16 terminations of pregnancy (1 for fetal abnormalities, 15 maternal choice); 19 1st trimester miscarriages; and 71 completed pregnancies (53 fwCF) with 73 live births (2 sets of twins).There were no maternal deaths or critical care admissions during pregnancy, and no infant deaths. Admissions for pulmonary exacerbations occurred in 20 pregnancies (28%). Most fwCF continued CFTRm throughout pregnancy in, of the 12 who paused CFTRm 9 (75%) restarted due to significant health decline.The majority of pregnancies (40/71, 56%) were in fwCF with moderate-severe FEV1 impairment. Severe lung function impairment was associated with a greater risk of antenatal IECF requiring hospitalisation.Abstract S71 Table 1 ppFEV1 >80% (n=31) ppFEV1 50- 80% (n=31) ppFEV1 <50% (n=9) p-value Mean ppFEV1 pre-conception mean ±SD) 97% ± 15 65% ± 7 42% ± 4 <0.001 Mean age (yrs, mean ±SD) 31 ± 4.7 31 ± 5.3 27.8 ± 5.8 0.17 CFTRm (all or part of pregnancy) n(%) 21 (68%) 28 (90%) 7 (78%) 0.35 Pre-term birth (<37 weeks) 5 (16%) 8 (26%) 3 (33%) 0.67 Gestation at delivery (weeks+days, mean ±SD) 37+5 ±10 days 37+3 ± 15 days 36+4 ± 11 days 0.24 Hospital admissions for IECF during pregnancy 5 (16%) 10 (32%) 5 (56%) 0.03 PE during pregnancy 0 1 0 1 Massive Haemoptysis in pregnancy 0 0 0 1 Pneumothorax in pregnancy 0 0 0 1 c-section delivery 13 (42%) 15 (48%) 7 (78%) 0.25 Conclusion CF-pregnancies are increasingly prevalent among fwCF previously cautioned against pregnancy. Overall reassuring outcomes among fwCF with moderate-severe spirometric impairment highlights the importance of continued health stabilisation conferred by CFTRm and dedicated specialist CF-pulmonary and obstetric support in this cohort, as they are still more likely to deliver pre-term and require admission to hospital during pregnancy. Research is ongoing to define optimal CF-obstetric management strategies and update the evidence base.References Edenborough FP, Borgo G, Knoop C, Lannefors L, Mackenzie WE, Madge S, et al. Guidelines for the management of pregnancy in women with cystic fibrosis. Journal of Cystic Fibrosis. 2008 Jan;7:S2–32.Ashcroft A, Chapman S, Mackillop L. The outcome of pregnancy in women with cystic fibrosis: a UK population-based descriptive study. BJOG. 2020 Dec 16;127(13):1696–703.",
  "authors": [
    {
      "affiliations": [
        "Royal Brompton Hospital, London, UK"
      ],
      "name": "A Downes"
    },
    {
      "affiliations": [
        "Royal Brompton Hospital, London, UK"
      ],
      "name": "L Weitnauer"
    },
    {
      "affiliations": [
        "Royal Brompton Hospital, London, UK"
      ],
      "name": "R Robinson"
    },
    {
      "affiliations": [
        "Royal Brompton Hospital, London, UK"
      ],
      "name": "E Diable"
    },
    {
      "affiliations": [
        "Chelsea and Westminster Hospital, London, UK"
      ],
      "name": "R Scott"
    },
    {
      "affiliations": [
        "Royal Brompton Hospital, London, UK"
      ],
      "name": "I Felton"
    }
  ],
  "title": "S71 Pre-conception lung function and the pregnancy outcomes among females with cystic fibrosis (fwCF) in the CF-transmembrane conductance regulator modulator (CFTRm) era",
  "uid": "e5e42f1a-74fc-5f34-af6f-c4791d2d27fb"
}