Cervical Ripening — Foley Catheter Versus Double-balloon Catheter for Cervical Ripening
Citation(s)
Pennell CE, Henderson JJ, O'Neill MJ, McChlery S, Doherty DA, Dickinson JE Induction of labour in nulliparous women with an unfavourable cervix: a randomised controlled trial comparing double and single balloon catheters and PGE2 gel. BJOG. 2009 Oct;116(11):1443-52. doi: 10.1111/j.1471-0528.2009.02279.x. Epub 2009 Jul 28. Erratum in: BJOG. 2011 Mar;118(4):521. McCleery, S [corrected to McChlery, S].
Sayed Ahmed WA, Ibrahim ZM, Ashor OE, Mohamed ML, Ahmed MR, Elshahat AM Use of the Foley catheter versus a double balloon cervical ripening catheter in pre-induction cervical ripening in postdate primigravidae. J Obstet Gynaecol Res. 2016 Nov;42(11):1489-1494. doi: 10.1111/jog.13086. Epub 2016 Jul 19.
Foley Catheter Versus Double-balloon Catheter for Cervical Ripening in Women With a High-risk Pregnancy
Interventional studies are often prospective and are specifically tailored to evaluate direct impacts of treatment or preventive measures on disease.
Observational studies are often retrospective and are used to assess potential causation in exposure-outcome relationships and therefore influence preventive methods.
Expanded access is a means by which manufacturers make investigational new drugs available, under certain circumstances, to treat a patient(s) with a serious disease or condition who cannot participate in a controlled clinical trial.
Clinical trials are conducted in a series of steps, called phases - each phase is designed to answer a separate research question.
Phase 1: Researchers test a new drug or treatment in a small group of people for the first time to evaluate its safety, determine a safe dosage range, and identify side effects.
Phase 2: The drug or treatment is given to a larger group of people to see if it is effective and to further evaluate its safety.
Phase 3: The drug or treatment is given to large groups of people to confirm its effectiveness, monitor side effects, compare it to commonly used treatments, and collect information that will allow the drug or treatment to be used safely.
Phase 4: Studies are done after the drug or treatment has been marketed to gather information on the drug's effect in various populations and any side effects associated with long-term use.