Postpartum haemorrhage and risk of long-term hypertension and cardiovascular disease: an English population-based longitudinal study using linked primary and secondary care databases

Predictors of Postpartum Hemorrhage and Associated Outcomes at a Midwest Academic Medical Center

Background

Postpartum hemorrhage (PPH) remains a significant cause of maternal morbidity and mortality around the world, with rates increasing in the United States. The objective of this study was to determine predictors of, and outcomes associated with, PPH at a Midwest academic health center.

Methods

Demographic and clinical data were obtained from the electronic medical record on all consecutive delivering patients between May 1, 2020, and April 30, 2021. Associations between PPH and perinatal characteristics and outcomes were assessed using logistic regression models. A significance threshold of 0.05 was used for all comparisons.

Results

Of the 2497 delivering patients during the study period, 437 (18%) experienced PPH. Chronic hypertension, gestational hypertension, and preeclampsia with and without severe features were all associated with increased odds of PPH (odds rations [ORs], respectively, 1.61 (95% CI:1.13-2.24, p = 0.006), 1.62 (95% CI 1.18-2.21, p = 0.003), 1.81 (95% CI 1.14-2.80, p ≤ 0.001), and 1.92 (95% CI 1.29-2.82, p = 0.009). There were also increased odds of PPH with type I diabetes: 2.83 (95% CI 1.45-5.30, p = 0.001), type II diabetes: 2.14 (95% CI 1.15-3.82, p = 0.012), twin delivery: 3.20 (95% CI 2.11-4.81, p ≤ 0.001), cesarean delivery: 5.66 (95% CI 4.53-7.09, p ≤ 0.001), and assisted vaginal delivery: 3.12 (95% CI1.95-4.88, p ≤ 0.001). Infants of mothers with PPH had high odds of NICU admission (CI = 1.34-2.07, p < 0.001) and hypoxic ischemic encephalopathy (CI = 1.64-7.14, p < 0.001).

Conclusion

Our findings confirm previous literature that preexisting and pregnancy-related hypertension, diabetes mellitus, multiple gestation, cesarean delivery, and assisted vaginal delivery are important predictors of PPH. In addition, we found that neonates of mothers with PPH had more adverse outcomes. These results may help to inform clinical care as rates of PPH continue to rise in the United States.

Postpartum haemorrhage occurring in UK midwifery units: A national population-based case-control study to investigate incidence, risk factors and outcomes

OBJECTIVES

To estimate the incidence of, and investigate risk factors for, postpartum haemorrhage (PPH) requiring transfer to obstetric care following birth in midwifery units (MU) in the UK; to describe outcomes for women who experience PPH requiring transfer to obstetric care.

METHODS

We conducted a national population-based case-control study in all MUs in the UK using the UK Midwifery Study System (UKMidSS). Between September 2019 and February 2020, 1501 women with PPH requiring transfer to obstetric care following birth in an MU, and 1475 control women were identified. We used multivariable logistic regression, generating adjusted odds ratios (aORs) and 95% confidence intervals (CIs) to investigate risk factors for PPH requiring transfer to obstetric care.

RESULTS

The incidence of PPH requiring transfer to obstetric care following birth in an MU was 3.7% (95% CI 3.6%-3.9%). Factors independently associated with PPH requiring transfer to obstetric care were smoking during pregnancy (aOR = 0.73; 95% CI 0.56-0.94), nulliparity (aOR = 1.96; 95% CI 1.66-2.30), previous PPH (aOR = 2.67; 95% CI 1.67-4.25), complications in a previous pregnancy other than PPH (aOR = 2.40; 95% CI 1.25-4.60), gestational age ≥41 weeks (aOR = 1.36; 95% CI 1.10-1.69), instrumental birth (aOR = 2.69; 95% CI 1.53-4.72), third stage of labour ≥60 minutes (aOR = 5.56; 95% CI 3.93-7.88), perineal trauma (aOR = 4.67; 95% CI 3.16-6.90), and birthweight 3500-3999g (aOR = 1.71; 95% CI 1.42-2.07) or ≥4000g (aOR = 2.31; 95% CI 1.78-3.00). One in ten (10.6%) cases received a blood transfusion and one in five (21.0%) were admitted to higher level care.

CONCLUSIONS

The risk factors identified in this study align with those identified in previous research and with current guidelines for women planning birth in an MU in the UK. Maternal outcomes after PPH were broadly reassuring and indicative of appropriate management. NHS organisations should ensure that robust guidelines are in place to support management of PPH in MUs.

Primary postpartum haemorrhage and longer-term physical, psychological, and psychosocial health outcomes for women and their partners in high income countries: A mixed-methods systematic review

OBJECTIVES

Most research about outcomes following postpartum haemorrhage (PPH) has focused on immediate outcomes. There are fewer studies investigating longer-term maternal morbidity following PPH, resulting in a significant knowledge gap. This review aimed to synthesize the evidence about the longer-term physical and psychological consequences of primary PPH for women and their partners from high income settings.

METHODS

The review was registered with PROSPERO and five electronic databases were searched. Studies were independently screened against the eligibility criteria by two reviewers and data were extracted from both quantitative and qualitative studies that reported non-immediate health outcomes of primary PPH.

RESULTS

Data were included from 24 studies, of which 16 were quantitative, five were qualitative and three used mixed-methods. The included studies were of mixed methodological quality. Of the nine studies reporting outcomes beyond five years after birth, only two quantitative studies and one qualitative study had a follow-up period longer than ten years. Seven studies reported outcomes or experiences for partners. The evidence indicated that women with PPH were more likely to have persistent physical and psychological health problems after birth compared with women who did not have a PPH. These problems, including PTSD symptoms and cardiovascular disease, may be severe and extend for many years after birth and were more pronounced after a severe PPH, as indicated by a blood transfusion or hysterectomy. There was limited evidence about outcomes for partners after PPH, but conflicting evidence of association between PTSD and PPH among partners who witnessed PPH.

CONCLUSION

This review explored existing evidence about longer-term physical and psychological health outcomes among women who had a primary PPH in high income countries, and their partners. While the evidence about health outcomes beyond five years after PPH is limited, our findings indicate that women can experience long lasting negative impacts after primary PPH, including PTSD symptoms and cardiovascular disease, extending for many years after birth.

PROSPERO REGISTRATION

PROSPERO registration number: CRD42020161144.