Recurrence of retained placenta in multiple consecutive deliveries

Racial and ethnic disparities in the incidence, healthcare utilization, and outcomes of retained placenta among delivery hospitalizations in the United States, 2016-2019

BACKGROUND

Retained placenta is a concern during labor and delivery. However, recent data regarding the profiles of retained placenta are scarce, especially nationwide and in minority populations. This study aimed to investigate the recent incidence of retained placenta and its associated outcomes.

METHODS

We retrospectively analyzed an American population-based data from the National Inpatient Sample (NIS) 2016-2019. The outcomes of interest included the incidence of retained placenta, in-hospital mortality, length of hospital stay, and hospitalization costs. We estimated the incidence for retained placenta overall and by racial and ethnic subgroups, utilizing survey weights standardized for each subgroup. Multivariable linear or logistic regression models were employed in our study to investigate the associations between retained placenta and the impact of in-hospital mortality, duration of stay, and hospitalization expenditures for the entire population and further stratified by race and ethnicity, adjusting for potential confounders.

RESULTS

Of the 13,848,131 deliveries, there were 108,035 (or 0.78%) birthing persons were identified as having retained placentas. Over time, the incidence of retained placenta increased from 730 per 100,000 (0.73%) in 2016 to 856 per 100,000 (0.86%) in 2019. Native American mothers have the highest rate of retained placenta, with a prevalence almost twice that of the general population, reaching 1,434 cases per 100,000 (1.43%). After adjusting for confounding factors, Native American mothers were more likely to have retained placenta (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.35-1.81), whereas Black (OR, 0.92; 95% CI, 0.88-0.97) and Hispanic mothers (OR, 0.84; 95% CI, 0.80-0.89) were significantly less likely to have retained placenta than White mothers. Furthermore, those who delivered with a retained placenta were significantly associated with higher in-hospital mortality, a longer duration of stay, and hospitalization expenditures, which were disproportionately varied by maternal race and ethnicity.

CONCLUSIONS

The incidence of retained placenta among people undergoing vaginal delivery is exhibiting an upward trend over time, with notable variations observed across different ethnic groups by unclear mechanisms. The ramifications of these findings have the potential to impact the clinical management of maternal health care and the creation of health policies, specifically in relation to the Native American birth population.

Risk factors for postpartum hemorrhage in patients with retained placenta: building a predict model

OBJECTIVES

Among patients with placenta retention, the risk factors of massive blood loss remain unclear. In this study, a secondary data analysis was conducted to construct a predictive risk model for postpartum hemorrhage (PPH) in this particular population.

METHODS

A prediction model based on the data of 13 hospitals in the UK, Uganda, and Pakistan, from December 2004, to May 2008 was built. A total of 516 patients and 14 potential risk factors were analyzed. The least absolute shrinkage and selection operator regression (LASSO) model was used to optimize feature selection for the PPH risk model. Multivariable logistic regression analysis was applied to build a prediction model incorporating the LASSO model. Discrimination and calibration were assessed using C-index and calibration plot.

RESULTS

Among patients with placenta retention, the incidence of PPH was 62.98% (325/526). Risk factors in the model were country, number of past deliveries, previous manual removal of placenta, place of placenta delivery, and how the placenta was delivered. In these factors, patients in the low-income country (i.e., Uganda) (OR: 1.753, 95% CI=1.055-2.915), retained placentas delivered in the theater (OR: 2.028, 95% CI=1.016-4.050), and having placentas partially removed by controlled cord traction (cct), completely removed manually (OR: 4.722, 95% CI=1.280-17.417) were independent risk factors. The C-statistics was 0.702.

CONCLUSIONS

By secondary data analysis, our study constructed a prediction model for PPH in patients with placenta retention, and identified the independent risk factors.

Maternal and Neonatal Outcomes in Twin Deliveries with Prolonged Second-Stage Duration of the Presenting Twin: a Retrospective Cohort Study

To assess the risk of adverse maternal and neonatal outcomes as a function of the presenting twin second-stage duration. A retrospective cohort study of deliveries taking place in an academic medical center between 2005 and 2019. The study group included women with twin pregnancies with the first fetus in vertex presentation, who attempted vaginal delivery with epidural analgesia and attained the second stage of labor. Prolonged second stage (PSS) was defined as when exceeding the 95th percentile of presenting twin second-stage duration recorded among all parturients who achieved spontaneous vaginal deliveries in our center during the study period, stratified by parity: 3 h in nulliparas and 1 h in multiparas. Women with and without PSS were compared. The primary outcome was a composite of adverse maternal outcomes. A univariate analysis was conducted and followed by multivariate analysis. During the study period, 1,337 parturients (36% of twin deliveries) met study criteria, of these 22% (298) were nulliparous and 78% (1,039) were multiparous. The second stage of labor of the presenting twin was prolonged in 41 (13.8%) of the nulliparas and 64 (6.2%) multiparas. Prolonged second stage was associated with episiotomy, chorioamnionitis, endometritis, and blood product transfusion, as well as vacuum deliveries of the first and second twin, second-stage cesarean, and a higher rate of composite adverse maternal outcome in nulliparous (41.5% vs. 20.2%, p<0.01) and with higher rates of episiotomy, postpartum hemorrhage, and vacuum deliveries of the first and second twin, but a similar rate of composite adverse maternal outcome in multiparous women (7.8% vs. 9.3%, p=0.68); moreover, the composite adverse neonatal outcome was not increased in nulliparous (36.6% vs. 38.5%, p=0.81) nor in multiparous women (21.9% vs. 23.6%, p=0.75). Prolonged second stage of labor of the presenting twin was associated with an adverse composite maternal outcome in nulliparous and with postpartum hemorrhage in multiparous. Further larger studies are warranted to reinforce our findings.

Rescue antenatal corticosteroids and neonatal outcomes in twin gestation

OBJECTIVE

Although repeated antenatal corticosteroids (ACS) courses are not recommended, a single rescue ACS course has been shown to decrease neonatal morbidity among preterm singletons. However, little is known regarding the effects of rescue ACS course in twin pregnancies.

METHODS

A retrospective cohort study conducted during 2015-2017 at a tertiary-care center including all twins delivered between 24-34 weeks of gestation who received at least one course of ACS.

RESULTS

Overall, 162 (70.4%) twins were exposed to a single ACS course and 68 (29.6%) to an additional rescue ACS course. Rescue ACS course was associated with lower rates of respiratory distress syndrome (7.4% vs. 19.1%, p = .03), surfactant use (7.4% vs 18.5%, p = .04) and bronchopulmonary dysplasia (0 vs 8.6%, p = .01) as compared to a single ACS course. In the rescue ACS group, compared to the single ACS group, the rates of composite respiratory adverse outcome (10.3% vs 22.2%, OR [95% CI]: 0.40 (0.17-0.95), p = .04) and any adverse neonatal outcome (13.2% vs 26.5%, OR [95% CI]: 0.42 (0.19-0.92), p = .04) were significantly lower. Hospital stay was also shorter among neonates born to mothers receiving a rescue ACS course (median 23 vs. 30 days, p = .01). No differences were noted in neonatal birthweight, head circumference and the rate of neonatal hypoglycemia.

CONCLUSION

Rescue ACS course was associated with improved respiratory and neonatal outcomes in twin gestations. Further studies are warranted to confirm our findings and better delineate the optimal regimen of rescue ACS in this setting.

Midwife annual delivery workload and maternal and neonatal adverse outcomes, is there an association?

OBJECTIVE

In recent years there has been growing interest in the relationship between the workload of an individual practitioner and its short- and long-term consequences on birth outcomes. In this respect, data is limited with regard to midwives' workload. We aimed to evaluate the association between midwives' annual birth workload and the short-term, adverse maternal and neonatal outcomes occurring at birth.

STUDY DESIGN

This retrospective cohort study was performed in a single tertiary academic center between 2006 and 2018. All single, live vertex term vaginal births were included and categorized into two groups based on the midwife's median annual volume of births during the study duration. The "high-volume" and "low-volume" groups included births above and below the median annual volume, respectively as a dichotomous variable. Further analyses were performed for the annual volume by deciles. Short term maternal and neonatal outcomes were compared between groups and between deciles.

RESULTS

During the study period 140,856 births met the study criteria. The median annual volume of births of a single midwife was 152 [114-195]. Maternal and labor characteristics were comparable between the groups. Maternal outcomes were not significantly associated with the midwifes' annual workload. However, neonates delivered by midwives with "low" annual volume had higher rate of neonatal jaundice (aOR 1.07, 95 % CI [1.00-1.14]) and mechanical ventilation (aOR 1.32, 95 % CI [1.05-1.66).

CONCLUSION

Adverse perinatal outcomes are only mildly affected by midwives' annual volume after controlling for the midwife, parturient and neonate's characteristics.

Risk factors for non-adherent retained placenta after vaginal delivery: a systematic review

Background

Retained placenta represents a cause of maternal morbidity and mortality affecting 0.5–3% of all vaginal deliveries. The unpredictability of this condition makes difficult to develop predictive and preventive strategies to apply in clinical practice. This analysis collected and analyzed all known risk factors related to this obstetric complication.

Methods

A systematic literature review for all original research articles published between 1990 and 2020 was performed. Observational studies about retained placenta risk factors published in English language were considered eligible. Conference abstracts, untraceable articles and studies focused on morbidly adherent placenta were excluded. The included articles were screened to identify study design, number of enrolled patients and retained placenta risk factors investigated. All stages of the revision followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) Statement.

Results

Thirty-five studies met the inclusion criteria. The reported retained placenta prevalence ranged from 0.5 to 4.8%. Maternal age, previous cesarean sections, previous dilation and curettage, previous retained placenta, labor induction, resulted as the most recurrent, independent risk factors for retained placenta. Previous estro-progestins therapy, morphological placental features (weight, shape, insertion of umbilical cord, implantation site), endometriosis, Assisted Reproductive Technologies, Apgar score are fascinating new proposal risk factors.

Conclusions

Old and new data are not enough robust to draw firm conclusions. Prospective and well-designed studies, based on a well agreed internationally retained placenta definition, are needed in order to clarify this potential dramatic and life-threatening condition.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12884-021-03721-9.