title: A Time Interval of More Than 18 Months Between a Pregnancy and a Roux-en-Y Gastric Bypass Increases the Risk of Iron Deficiency and Anaemia in Pregnancy.
abstract: The aim of the study is to explore the impact of time between Roux-en-Y gastric bypass (RYGB) and pregnancy on obstetrical outcome and nutritional derangements.
  
  
  
  In a retrospective cross-sectional study of pregnant women admitted for antenatal care at two tertiary hospitals, we examined 153 women with RYGB and a singleton pregnancy of at least 24 weeks. The women were stratified according to a pregnancy <18 months (40 women) or ≥18 months (113 women) after RYGB. Main outcome measures were nutritional parameters and glycated haemoglobin 1Ac (HbA1c) in second and third trimester of pregnancy, gestational hypertension, length of pregnancy, mode of delivery and foetal birth weight.
  
  
  
  The two groups were comparable regarding age, parity and prepregnancy body mass index. The frequency of iron deficiency anaemia (ferritin <12 μg/L and haemoglobin <6.5 mmol/L/10.5 g/dL) was significantly higher in the late group, 29 vs. 8 % in the early group, p = 0.010. No differences were found for vitamin B12, vitamin D and zinc. Median HbA1c was significantly higher in the late group than in the early group (33 vs. 31 mmol/mol, p = 0.027). There were no significant differences in the risk of adverse pregnancy outcome or birth weight between the two groups.
  
  
  
  A long surgery-to-pregnancy time interval after a RYGB increases the risk of iron deficiency anaemia but not of other nutritional deficits. Time interval does not seem to have an adverse effect on the obstetrical outcome, including intrauterine growth restriction. Specific attention is needed on iron deficit with increasing surgery-to-pregnancy time interval.
authors.affiliation: Department of Obstetrics and Gynecology, Copenhagen University Hospital Herlev, Herlev, Denmark.
authors.forename: Mie
authors.initials: M
authors.lastname: Crusell
authors.affiliation: Department of Obstetrics andGynecology, Copenhagen University Hospital Hvidovre, Hvidovre, Denmark.
authors.forename: Lisbeth
authors.initials: L
authors.lastname: Nilas
authors.affiliation: Department of Obstetrics and Gynecology, Copenhagen University Hospital Herlev, Herlev, Denmark.
authors.forename: Jens
authors.initials: J
authors.lastname: Svare
authors.affiliation: Department of Obstetrics and Gynecology, Copenhagen University Hospital Herlev, Herlev, Denmark. jeannet@lauenb.org.
authors.forename: Jeannet
authors.initials: J
authors.lastname: Lauenborg
mesh_terms: D000328:Adult; D000740:Anemia / Q000097:blood / Q000209:etiology; D018798:Anemia, Iron-Deficiency / Q000097:blood / Q000209:etiology*; D003430:Cross-Sectional Studies; D005260:Female; D005293:Ferritins / Q000097:blood; D015390:Gastric Bypass / Q000009:adverse effects*; D006801:Humans; D009748:Nutrition Disorders / Q000097:blood / Q000209:etiology*; D009765:Obesity / Q000097:blood / Q000601:surgery*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000097:blood / Q000209:etiology*; D011256:Pregnancy Outcome; D011295:Prenatal Care; D012189:Retrospective Studies; D013997:Time Factors
chemical_list: D005293:Ferritins
keywords: Anaemia; Pregnancy; Pregnancy complications; Roux-en-Y gastric bypass; Time interval; Vitamin deficiency