Intra-umbilical vein injection and retained placenta: evidence from a collaborative large randomised controlled trial. Grupo Argentino de Estudio de Placenta Retenida

Umbilical vein injection for management of retained placenta

BACKGROUND

Retained placenta is a common complication of pregnancy affecting 1% to 6% of all births. If a retained placenta is left untreated, spontaneous delivery of the placenta may occur, but there is a high risk of bleeding and infection. Manual removal of the placenta (MROP) in an operating theatre under anaesthetic is the usual treatment, but is invasive and may have complications. An effective non-surgical alternative for retained placenta would potentially reduce the physical and psychological trauma of the procedure, and costs. It could also be lifesaving by providing a therapy for settings without easy access to modern operating theatres or anaesthetics. Injection of uterotonics into the uterus via the umbilical vein and placenta is an attractive low-cost option for this. This is an update of a review last published in 2011.

OBJECTIVES

To assess the use of umbilical vein injection (UVI) of saline solution with or without uterotonics compared to either expectant management or with an alternative solution or other uterotonic agent for retained placenta.

SEARCH METHODS

For this update, we searched Cochrane Pregnancy and Childbirth's Trials Register, ClinicalTrials.gov, the WHO International Clinical Trials Registry Platform (14 June 2020), and reference lists of retrieved studies.

SELECTION CRITERIA

Randomised controlled trials (RCTs) comparing UVI of saline or other fluids (with or without uterotonics), either with expectant management or with an alternative solution or other uterotonic agent, in the management of retained placenta. We considered quasi-randomised, cluster-randomised, and trials reported only in abstract form.

DATA COLLECTION AND ANALYSIS

Two review authors independently assessed trials for inclusion and risk of bias, extracted data, and checked them for accuracy. We assessed the certainty of the evidence using the GRADE approach. We calculated pooled risk ratios (RRs) and mean differences (MDs) with 95% confidence intervals (CIs), and presented results using 'Summary of findings' tables.

MAIN RESULTS

We included 24 trials (n = 2348). All included trials were RCTs, one was quasi-randomised, and none were cluster-randomised. Risk of bias was variable across the included studies. We assessed certainty of evidence for four comparisons: saline versus expectant management, oxytocin versus expectant management, oxytocin versus saline, and oxytocin versus plasma expander. Evidence was moderate to very-low certainty and downgraded for risk of bias of included studies, imprecision, and inconsistency of effect estimates. Saline solution versus expectant management There is probably little or no difference in the incidence of MROP between saline and expectant management (RR 0.93, 95% CI 0.80 to 1.10; 5 studies, n = 445; moderate-certainty evidence). Evidence for the following remaining primary outcomes was very-low certainty: severe postpartum haemorrhage 1000 mL or greater, blood transfusion, and infection. There were no events reported for maternal mortality or postpartum anaemia (24 to 48 hours postnatal). No studies reported addition of therapeutic uterotonics. Oxytocin solution versus expectant management UVI of oxytocin solution might slightly reduce in the need for manual removal compared with expectant management (mean RR 0.73, 95% CI 0.56 to 0.95; 7 studies, n = 546; low-certainty evidence). There may be little to no difference between the incidence of blood transfusion between groups (RR 0.81, 95% CI 0.47 to 1.38; 4 studies, n = 339; low-certainty evidence). There were no maternal deaths reported (2 studies, n = 93). Evidence for severe postpartum haemorrhage of 1000 mL or greater, additional uterotonics, and infection was very-low certainty. There were no events for postpartum anaemia (24 to 48 hours postnatal). Oxytocin solution versus saline solution UVI of oxytocin solution may reduce the use of MROP compared with saline solution, but there was high heterogeneity (RR 0.82, 95% CI 0.69 to 0.97; 14 studies, n = 1370; I² = 54%; low-certainty evidence). There were no differences between subgroups according to risk of bias or oxytocin dose for the outcome MROP. There may be little to no difference between groups in severe postpartum haemorrhage of 1000 mL or greater, blood transfusion, use of additional therapeutic uterotonics, and antibiotic use. There were no events for postpartum anaemia (24 to 48 hours postnatal) (very low-certainty evidence) and there was only one event for maternal mortality (low-certainty evidence). Oxytocin solution versus plasma expander One small study reported UVI of oxytocin compared with plasma expander (n = 109). The evidence was very unclear about any effect on MROP or blood transfusion between the two groups (very low-certainty evidence). No other primary outcomes were reported. For other comparisons there were little to no differences for most outcomes examined. However, there was some evidence to suggest that there may be a reduction in MROP with prostaglandins in comparison to oxytocin (4 studies, n = 173) and ergometrine (1 study, n = 52), although further large-scale studies are needed to confirm these findings.

AUTHORS' CONCLUSIONS

UVI of oxytocin solution is an inexpensive and simple intervention that can be performed when placental delivery is delayed. This review identified low-certainty evidence that oxytocin solution may slightly reduce the need for manual removal. However, there are little or no differences for other outcomes. Small studies examining injection of prostaglandin (such as dissolved misoprostol) into the umbilical vein show promise and deserve to be studied further.

Pharmacologic intervention for retained placenta: a systematic review and meta-analysis

OBJECTIVE

To assess the effectiveness and safety of pharmacologic interventions for the treatment of retained placenta (when the placenta remains undelivered after 30 minutes of active management of the third stage of labor).

DATA SOURCES

We searched: 1) Cochrane Central Register of Controlled Trials (CENTRAL), 2) Cochrane Pregnancy and Childbirth Group's Trials Register, 3) EMBASE, and 4) MEDLINE from inception to June 2014.

METHODS OF STUDY SELECTION

Randomized controlled trials comparing a pharmacologic intervention(s) with a placebo for the treatment of retained placenta were included.

TABULATION, INTEGRATION, AND RESULTS

Sixteen randomized controlled trials, including 1,683 participants, were included. Study characteristics and quality were recorded. The meta-analysis was based on random-effects methods for pooled data. There were no statistically significant differences in the requirement to perform manual removal of a placenta in patients treated with oxytocin (55% compared with 60%; relative risk [RR] 0.86, 95% confidence interval [CI] 0.73-1.02; 10 randomized controlled trials [RCTs]), prostaglandins (44% compared with 55%; RR 0.82, 95% CI 0.58-1.15; four RCTs), nitroglycerin (85% compared with 80%; RR 1.06, 95% CI 0.80-1.41; one RCT), or oxytocin and nitroglycerin (52% compared with 79%; RR 0.23, 95% CI 0.01-8.48; two RCTs) compared with placebo. There was limited reporting of secondary outcomes.

CONCLUSION

As opposed to the use of oxytocin as part of the active management of the third stage of labor that has been shown to diminish bleeding in the third stage, once the diagnosis of retained placenta has been made, no pharmacologic treatment has been shown to be effective. When retained placenta is diagnosed, immediate manual removal of the placenta should be considered.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO International Prospective Register of Systematic Reviews, http://www.crd.york.ac.uk/PROSPERO/, CRD42014010641.

Myomectomy for retained placenta due to incarcerated fibroid mass

Retained placenta is one of the most common complications of preterm delivery and/or mid-trimester miscarriage. It is an important cause of increased maternal morbidity and sometimes mortality especially in developing countries. It is associated with several complications that could be tasking to the facility and of great challenge to the obstetrician. Here we present a very rare event in obstetrics which is retained placenta due to incarcerated, posteriorly-sited fibroid that was successfully managed with myomectomy.

Retained placenta: Do we have any option?

Retained placenta is a known cause of post-partum haemorrhage and maternal mortality. A recent systemic review has confirmed that the incidence of retained placenta had increased all over the world, which is more common in developed countries. Failure of retro-placental myometrium contraction is the main cause of retained placenta. Maternal age greater than 35 years, grandmultipara, preterm labor, history of previous retained placenta, and caesarean section were the risk factors for retained placenta. Manual removal of the placenta has been the treatment of choice. Attempts had been made by clinician and researchers to find a safe, effective and reliable method to avoid the need for surgical intervention. The efficacy and safety of prostaglandin, nitroglycerin or acupuncture in the management of retained placenta are yet to be further evaluated. Nonetheless, till date only intra-umbilical vein oxytocin has been studied extensively but with varied success. More randomized clinical trials are needed to address this issue. However, if immediate manual placenta removal service is unavailable, a trial of intra-umbilical vein oxytocin 100 IU at a total volume of at least 40 mL while preparing for transfer to a tertiary center or theatre may result in spontaneous expulsion of the placenta.

Umbilical vein injection of misoprostol versus normal saline for the treatment of retained placenta: intrapartum placebo-controlled trial

BACKGROUND

The third stage of labour may be complicated by retained placenta, which should be managed promptly because it may cause severe bleeding and infection, with a potentially fatal outcome. This study evaluated the effectiveness of umbilical vein injection of misoprostol for the treatment of retained placenta in a hospital setting.

METHODS

This hospital-based placebo-controlled trial was conducted at the Maternity Teaching Hospital, Erbil City, Kurdistan region, Northern Iraq from April 2011 to February 2012. The inclusion criteria were: gestational age of at least 28 weeks, vaginal delivery, and failure of the placenta to separate within 30 minutes after delivery of the infant despite active management of the third stage of labour. Forty-six women with retained placentas were eligible for inclusion. After informed consent was obtained, the women were alternately allocated to receive umbilical vein injection of either 800 mcg misoprostol dissolved in 20 mL of normal saline (misoprostol group) or 20 mL of normal saline only (saline group). The women were blinded to the group allocation, but the investigator who administered the injection was not. The trial was registered by the Research Ethics Committee of Hawler Medical University.

RESULTS

After umbilical vein injection, delivery of the placenta occurred in 91.3% of women in the misoprostol group and 69.5% of women in the saline group, which was not a significant difference between the two groups. The median vaginal blood loss from the time of injection until delivery of the placenta was significantly less in the misoprostol group (100 mL) than in the saline group (210 mL) (p value < 0.001).

CONCLUSION

Umbilical vein injection of misoprostol is an effective treatment for retained placenta, and reduces the volume of vaginal blood loss with few adverse effects.

CLINICAL TRIAL REGISTRATION

Current Controlled Trial HMU: N252.1.2011.

Umbilical vein injection for management of retained placenta

BACKGROUND

If a retained placenta is left untreated, there is a high risk of maternal death. However, manual removal of the placenta is an invasive procedure with serious complications of haemorrhage, infection or genital tract trauma.

OBJECTIVES

To assess the use of umbilical vein injection (UVI) of saline solution alone or with oxytocin in comparison either with expectant management or with an alternative solution or other uterotonic agent for retained placenta.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group's Trials Register (28 February 2011).

SELECTION CRITERIA

Randomized trials comparing UVI of saline or other fluids, with or without oxytocics, either with expectant management or with an alternative solution or other uterotonic agent, in the management of retained placenta.

DATA COLLECTION AND ANALYSIS

Two review authors assessed the methodological quality of the studies and extracted the data.

MAIN RESULTS

We included 15 trials (1704 women). The trials were of variable quality. Compared with expectant management, UVI of saline solution alone did not show any significant difference in the incidence of manual removal of the placenta (risk ratio (RR) 0.99; 95% confidence interval (CI) 0.84 to 1.16). UVI of oxytocin solution compared with expectant management showed no reduction in the need for manual removal (RR 0.87; 95% CI 0.74 to 1.03).Oxytocin solution compared with saline solution alone showed a reduction in manual removal of the placenta, but this was not statistically significant (RR 0.91; 95% CI 0.82 to 1.00). When only high-quality studies were assessed, there was no statistical difference (RR 0.92; 95% CI 0.83 to 1.01). We detected no differences in any of the other outcomes.UVI of oxytocin solution compared with UVI of plasma expander showed no statistically significant difference in the outcomes assessed by the only one small trial included. Prostaglandin solution compared with saline solution alone was associated with a statistically significant lower incidence in manual removal of placenta (RR 0.42; 95% CI 0.22 to 0.82) but we observed no difference in the other outcomes evaluated. Prostaglandin plus saline solution showed a statistically significant reduction in manual removal of placenta when compared with oxytocin plus saline solution (RR 0.43; 95% CI 0.25 to 0.75), and we also observed a small reduction in time from injection to placental delivery (mean difference -6.00; 95% CI -8.78 to -3.22). However, there were only two small trials contributing to this meta-analysis.

AUTHORS' CONCLUSIONS

UVI of oxytocin solution is an inexpensive and simple intervention that could be performed while placental delivery is awaited. However, high-quality randomized trials show that the use of oxytocin has little or no effect. Further research into the optimal timing of manual removal and into UVI of prostaglandins or plasma expander is warranted.

Umbilical vein oxytocin in the management of retained placenta: an alternative to manual removal of placenta?

PURPOSE

Retained placenta is potentially life threatening due to possible complications associated with manual removal. Our aim was to determine whether umbilical vein injection of oxytocin in saline reduces the need for manual removal of placenta.

METHODS

This was a randomised controlled trial conducted at a tertiary hospital from December 2002 to March 2004. A total of 61 women delivering singletons, who had no sign of placental separation 20 min after vaginal delivery, were randomised to receive either intra-umbilical oxytocin 100 IU diluted in 30 ml of saline or controlled cord traction only. Manual removal was done if the placenta was not expelled in another 30 min in both arms.

RESULTS

There was a significant reduction in the rate of subsequent manual removal of placenta (30 vs. 67.7%, p < 0.05), incidence of uterine atony (3.3 vs. 25.8%, p < 0.05) and the need for uterotonic agents (33.3 vs. 64.5%, p < 0.05) in the oxytocin group when compared with the control group. No significant differences were found in the need for blood transfusion, uterine curettage, incidence of postpartum haemorrhage and haemoglobin level reduction.

CONCLUSION

Intra-umbilical vein oxytocin injection is clinically effective for the management of a retained placenta.

Umbilical vein oxytocin for the treatment of retained placenta (Release Study): a double-blind, randomised controlled trial

BACKGROUND

Retained placenta is associated with post-partum haemorrhage. Meta-analysis has suggested that umbilical injection of oxytocin could increase placental expulsion without the need for a surgeon or anaesthetic. We assessed the effect of high-dose umbilical vein oxytocin as a treatment for retained placenta.

METHODS

In this double-blind, placebo-controlled trial, haemodynamically stable women with a retained placenta for more than 30 min were recruited from 13 sites in the UK, Uganda, and Pakistan. 577 women were randomly assigned by a computer-generated randomisation list stratified by centre to 30 mL saline containing either 50 IU oxytocin (n=292) or 5 mL water (n=285), which was injected into the placenta through an umbilical vein catheter. All trial participants, study workers, and data handlers were masked to individual allocations. The primary outcome was the need for manual removal of the placenta. Analysis was by intention to treat. This study is registered, number ISRCTN 13204258.

FINDINGS

The primary outcome was recorded for all participants. We detected no difference between the groups in the need for manual removal of placenta (oxytocin 179/292 [61.3%] vs placebo 177/285 [62.1%]; relative risk 0.98, 95% CI 0.87-1.12; p=0.84). The need for manual removal was higher in the UK (overall 250/361 [69%]) than in Uganda (90/190 [47%]) or Pakistan (16/26 [62%]). Adverse events did not differ between the two groups.

INTERPRETATION

Umbilical oxytocin has no clinically significant effect on the need for manual removal for women with retained placenta.

FUNDING

WHO, WellBeing of Women, Pakistan Higher Education Commission.

The retained placenta

The incidence and importance of retained placenta (RP) varies greatly around the world. In less developed countries, it affects about 0.1% of deliveries but has up to 10% case fatality rate. In more developed countries, it is more common (about 3% of vaginal deliveries) but very rarely associated with mortality. There are three main types of retained placenta following the vagina delivery: placenta adherens (when there is failed contraction of the myometrium behind the placenta), trapped placenta (a detached placenta trapped behind a closed cervix) and partial accreta (when there is a small area of accreta preventing detachment). All can be treated by manual removal of placenta, which should be carried out at 30-60 minutes postpartum. Medical management is also an option for placenta adherens and trapped placenta. The need for manual removal can be reduced by 20% by the use of intraumbilical oxytocin (30 i.u. in 30 mL saline). A trapped placenta may respond to glyceryl trinitrate (500 mcg sublingually) or gentle, persistent, controlled cord traction.

Postpartum hemorrhage in developing countries: is the public health community using the right tools?

OBJECTIVES

To identify new and underutilized technologies that may assist in reducing maternal mortality due to obstetric hemorrhage.

METHODS

Review of published and unpublished literature, including systematic reviews of randomized trials and individual clinical studies.

RESULTS

Hemorrhage, primarily postpartum, accounts for approximately 25% of maternal deaths globally. Uterotonic drugs offer great promise for both prevention and management of postpartum hemorrhage (PPH). Other technologies--such as anti-shock garments, umbilical vein injection of oxytocin, and simple anemia detection methods--represent potential new opportunities to reduce PPH-related mortality.

CONCLUSIONS

Clinical and operational research is needed to answer remaining questions about misoprostol, the anti-shock garment, and umbilical vein injection of oxytocin for retained placenta. Efforts are needed to ensure the availability of technologies with proven value, such as oxytocin in Uniject prefilled injection devices. Equally important, technologies and techniques with proven efficacy--such as active management of third-stage labor and aortic compression--must be translated into general use by disseminating the evidence for them, incorporating them into national guidelines and training curricula, and ensuring the availability of supportive supplies and equipment.

The retained placenta

The retained placenta is a significant cause of maternal mortality and morbidity throughout the developing world. It complicates 2% of all deliveries and has a case mortality rate of nearly 10% in rural areas. Ultrasound studies have provided fresh insights into the mechanism of the third stage of labour and the aetiology of the retained placenta. Following delivery of the baby, the retro-placental myometrium is initially relaxed. It is only when it contracts that the placenta shears away from the placental bed and is detached. This leads to its spontaneous expulsion. Retained placenta occurs when the retro-placental myometrium fails to contract. There is evidence that this may also occur during labour leading to dysfunctional labour. It is likely that this is caused by the persistence of one of the placental inhibitory factors that are normally reduced prior to the onset of labour, possibly progesterone or nitric oxide. Presently, the only effective treatment is manual removal of placenta (MROP) under anaesthetic. This needs to be carried out within a few hours of delivery to avoid haemorrhage. For women in rural Africa, facilities for MROP are scarce, leading to high mortality rates. Injection of oxytocin into the umbilical vein has been suggested as an alternative. This method relies on the injected oxytocin passing through the placenta to contract the retro-placental myometrium and cause its detachment. Despite several placebo controlled trials of this technique, no firm conclusion have been reached regarding its efficacy. This may be due to inadequate delivery of the oxytocin to the placenta. Further trials are in progress to assess the optimal dose of oxytocin as well as the efficacy of a new technique designed to improve delivery of the oxytocin to the placental bed.

Manual removal of the placenta--a case control study

The aim of this study was to determine the incidence and complications related to manual removal of the placenta in a regional hospital in Australia. The study was carried out at the Goulburn Valley Base Hospital in Shepparton. The hospital medical records were reviewed from 1992 to 1999. A total of 3734 singleton live vaginal deliveries took place during the 7-year study period. The placenta was removed manually in 114 women (3%). For a control group, a series of 113 women who had singleton live vaginal deliveries from the same period were chosen at random. The case and control groups were similar in age, parity, and gravidity. A previous history of retained placenta and a history of preterm delivery in the current pregnancy were significantly related to retained placenta (OR 9.8 [95% CI 1.1-85.5] and OR 5.6 [95% CI 1.1-26.8], respectively). The cases received significantly more blood transfusions than the control group (13% versus 0%). Decreased maternal age was also significantly related to retained placenta. There were also more post-delivery dilatation and curettage (D&C) operations and diagnosis of endomyometritis in the case group. However, these differences were not statistically significant. One woman, in the case group, had to have a hysterectomy due to placenta accreta.

Umbilical vein injection for management of retained placenta

BACKGROUND

If a retained placenta is left untreated, there is a high risk of maternal death. However, manual removal of the placenta is an invasive procedure with its own serious complications of haemorrhage, infection or genital tract trauma.

OBJECTIVES

The objective of this review was to assess the use of umbilical vein injection of saline solution alone or with oxytocin in comparison either with expectant management or with an alternative solution or other uterotonic agent for retained placenta. The main comparisons include the following agents: saline solution alone, saline solution plus oxytocin, saline solution plus prostaglandin and plasma expander.

SEARCH STRATEGY

We searched the Cochrane Pregnancy and Childbirth Group trials register and the Cochrane Controlled Trials Register (latest search 20 March 2001).

SELECTION CRITERIA

Randomised trials comparing umbilical vein injection of saline or other fluids, with or without oxytocics, either with expectant management or with an alternative solution or other uterotonic agent, in the management of retained placenta.

DATA COLLECTION AND ANALYSIS

The two reviewers assessed trial quality and extracted data.

MAIN RESULTS

Twelve trials were included. The trials were of variable quality. Compared with expectant management, umbilical vein injection of saline solution alone did not show any significant difference in the incidence of manual removal of the placenta (relative risk (RR): 0.97; 95% confidence interval (CI): 0.83 to 1.14). Umbilical vein injection of saline solution plus oxytocin compared with expectant management showed a reduction in manual removal, although this was not statistically significant (RR: 0.86; 95% CI: 0.72 to 1.01). Saline solution with oxytocin compared with saline solution alone showed a significant reduction in manual removal of the placenta (RR: 0.79; 95% CI: 0.69 to 0.91) (number needed to treat: 8; 95% CI: 5 to 20). No discernible difference was detected in length of third stage of labour, blood loss, haemorrhage, haemoglobin, blood transfusion, curettage, infection, hospital stay, fever, abdominal pain and oxytocin augmentation. Umbilical vein injection of saline solution plus oxytocin compared with umbilical vein injection of plasma expander showed higher, but not statistically significant, incidence of manual removal of placenta (RR: 1.34; 95% CI: 0.97 to 1.85) and no difference in blood loss but there is only one small trial contributing to this comparison. Saline solution plus prostaglandin, compared with saline solution alone, was associated with a statistically significant lower incidence in manual removal of placenta (RR: 0.05; 95% CI: 0.00 to 0.73 ) but no difference was observed in blood loss, fever, abdominal pain, and oxytocin augmentation but there is only one small trial contributing to these results. There were no significant differences between saline solution plus prostaglandin and saline solution plus oxytocin (RR: 0.10; 95% CI: 0.01 to 1.59) but again there is only one small trial contributing to this meta-analysis.

REVIEWER'S CONCLUSIONS

Umbilical vein injection of saline solution plus oxytocin appears to be effective in the management of retained placenta. Saline solution alone does not appear be more effective than expectant management. Further research into umbilical vein injection of oxytocin, prostaglandins or plasma expander is warranted.