title: The safety of tocolytics used for the inhibition of preterm labour.
abstract: BACKGROUND
  Preterm birth is the major cause of neonatal mortality and morbidity worldwide and a huge cost burden on healthcare. Between 22 and 26 completed weeks of gestation, for every day that delivery is delayed, survival increases by 3%.
  
  
  METHODS
  Following a systematic review of the literature, we have provided an overview of the use of tocolytics for the prevention of preterm birth and have examined the fetal and maternal adverse effects of the various tocolytic agents currently in use.
  
  
  CONCLUSIONS
  No tocolytic currently in use was developed specifically to treat preterm labour so most have multi-organ side effects. β2-agonists are relatively safe for the fetus but have rare and potentially serious maternal adverse effects. In contrast, prostaglandin synthetase inhibitors have potentially serious side effects for the fetus and neonate but have mild maternal gastrointestinal side effects. In Europe, the choice of first line therapy is either atosiban or nifedipine. The evidence base for atosiban is much more robust than for nifedipine. While their efficacy is similar, atosiban has placebo level side effects and is safer than nifedipine but is much more expensive.
authors.affiliation: a Department of Medical Education , Lincoln County Hospital , Lincoln , UK.
authors.forename: Callum D
authors.initials: CD
authors.lastname: Lamont
authors.affiliation: b Department of Gynaecology and Obstetrics , Odense University Hospital , Odense , Denmark.|c Institute of Clinical Research, Research Unit of Gynaecology and Obstetrics , University of Southern Denmark , Odense , Denmark.|d Centre for Innovative Medical Technology , Odense University Hospital , Odense , Denmark.
authors.forename: Jan Stener
authors.initials: JS
authors.lastname: Jørgensen
authors.affiliation: b Department of Gynaecology and Obstetrics , Odense University Hospital , Odense , Denmark.|c Institute of Clinical Research, Research Unit of Gynaecology and Obstetrics , University of Southern Denmark , Odense , Denmark.|e Division of Surgery , University College London, Northwick Park Institute for Medical Research Campus , London , UK.
authors.forename: Ronald F
authors.initials: RF
authors.lastname: Lamont
mesh_terms: D000818:Animals; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D009543:Nifedipine / Q000009:adverse effects / Q000627:therapeutic use; D007752:Obstetric Labor, Premature / Q000517:prevention & control*; D011247:Pregnancy; D047928:Premature Birth / Q000517:prevention & control*; D015149:Tocolytic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D014668:Vasotocin / Q000009:adverse effects / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D015149:Tocolytic Agents; C047046:atosiban; D009543:Nifedipine; D014668:Vasotocin
keywords: Atosiban; adverse events; beta-agonists; calcium channel blockers; nifedipine; oxytocin receptor antagonists; preterm birth; preterm labour; prostaglandin synthetase inhibitors; ritodrine; safety; tocolytics