Background: Retained placenta affects 0.5% to 3% of women following delivery, with considerable morbidity if left untreated. Use of tocolytics, either alone or in combination with uterotonics, may be of value to minimise the need for manual removal of the placenta in theatre under anaesthesia.
Objectives: Evaluate the benefits and harms of tocolytics alone or in addition to uterotonics in the management of retained placenta in order to reduce the need for manual removal of placenta.
Search strategy: We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (31 October 2010) and contacted experts in the field.
Selection criteria: Any adequately randomised controlled trial (RCT) comparing the use of tocolytics, either alone or in combination with uterotonics, with no intervention or with other interventions in the management of retained placenta. All women having a vaginal delivery with a retained placenta, regardless of the management of the third stage of labour (expectant or active). We included all trials with haemodynamically stable women in whom the placenta was not delivered at least within 15 minutes after delivery of the baby.
Data collection and analysis: Two review authors independently assessed trial quality and extracted data. Consultation of the third author was done if needed.
Main results: We included one RCT (involving 24 women). It compared the use of nitroglycerin tablets versus placebo after the treatment with oxytocin failed. There was a statistically significant reduction in the need for manual removal of placenta (risk ratio (RR) 0.04, 95% confidence interval (CI) 0.00 to 0.66). There was also a statistically significant reduction in mean blood loss during the third stage of labour (mean difference (MD) -262.50 ml, 95% CI -364.95 to -160.05). Sublingual nitroglycerin caused some haemodynamic changes as it lowers the systolic blood pressure and diastolic blood pressure by a means of 6 and 5 mmHg respectively. Pulse rate increased by a mean of two beats per minute.
Authors' conclusions: Sublingual nitroglycerin, given when oxytocin fails, seems to reduce both the need for manual removal of placenta and blood loss during the third stage of labour when compared to placebo. Further trials are needed to confirm its clinical role and safety. Its routine use cannot be recommended based on a single small study. There is no evidence available for other types of tocolytics.