Inducing labour after 41 weeks of completed gestion is likely to reduce the risk of perinatal death and stillbirth compared with waiting for labour to start spontaneously.Inducing labor before 39 weeks in the absence of a medical indication (such as hypertension, IUGR, or pre-eclampsia) increases the risk of complications of prematurity including difficulties with respiration, infection, feeding, jaundice, neonatal intensive care unit admissions, and perinatal death.Inducing labour after 34 weeks and before 37 weeks in women with hypertensive disorders (pre-eclampsia, eclampsia, pregnancy-induced hypertension) may lead to better outcomes for the woman but does not improve or worsen outcomes for the baby. More research is needed to produce more certain results. If waters break (membranes rupture) between 24 and 37 weeks gestation, waiting for the labour to start naturally with careful monitoring of the woman and baby is more likely to lead to healthier outcomes. For women over 37 weeks pregnant whose babies are suspected of not coping well in the womb, it is not yet clear from research whether it is best to have an induction or caesarean immediately, or to wait until labour happens by itself. Similarly, there is not yet enough research to show whether it is best to deliver babies prematurely if they are not coping in the womb or whether to wait so that they are less premature when they are born.Clinicians assess the odds of having a vaginal delivery after labor induction by a "Bishop score".
Clinical guideline, UK National Institute for Health and Clinical Excellence, June 2001. Josie L. Tenore: Methods for cervical ripening and induction of labor Archived 2008-05-16 at the Wayback Machine. American Family Physician, 15 May 2003. "Catecholamines – blood ." National Library of Medicine . N.p., n.d. Web. 28 Mar. 2011. <https://www.nlm.nih.gov/medlineplus>.