Duration of the active first stage of labour and severe perineal lacerations and maternal postpartum complications: a population-based cohort study

OBJECTIVE

The impact of first stage labour duration on maternal outcomes is sparsely investigated. We aimed to study the association between a longer active first stage and maternal complications in the early postpartum period.

DESIGN

A population-based cohort study.

SETTING

Regions of Stockholm and Gotland, Sweden, 2008-2020.

POPULATION

A cohort of 159 459 term, singleton, vertex pregnancies, stratified by parity groups.

METHODS

The exposure was active first stage duration, categorised in percentiles. Poisson regression analysis was performed to estimate the adjusted relative risk (aRR) and the 95% confidence interval (95% CI). To investigate the effect of second stage duration on the outcome, mediation analysis was performed.

MAIN OUTCOME MEASURES

Severe perineal lacerations (third or fourth degree), postpartum infection, urinary retention and haematoma in the birth canal or ruptured sutures.

RESULTS

The risks of severe perineal laceration, postpartum infection and urinary retention increased with a longer active first stage, both overall and stratified by parity group. The aRR increased with a longer active first stage, using duration of <50th percentile as the reference. In the ≥90th percentile category, the aRR for postpartum infection was 1.64 (95% CI 1.46-1.84) in primiparous women, 2.43 (95% CI 1.98-2.98) in parous women with no previous caesarean delivery (CD) and 2.33 (95% CI 1.65-3.28) in parous women with a previous CD. The proportion mediated by second stage duration was 33.4% to 36.9% for the different outcomes in primiparous women. The risk of haematoma or ruptured sutures did not increased with a longer active first stage.

CONCLUSIONS

Increasing active first stage duration is associated with maternal complications in the early postpartum period.

Operative vaginal delivery as an independent risk factor for maternal postpartum infectious morbidity

BACKGROUND

A recent study from the United Kingdom suggested that a single dosage of adjunctive amoxicillin/clavulanic acid with operative vaginal delivery reduces maternal infectious morbidity by 40% (from 19% to 11%). However, 89% of their study population received an episiotomy.

OBJECTIVE

This study aimed to evaluate whether operative vaginal delivery is an independent risk factor for composite maternal postpartum infectious morbidity in a population with a low episiotomy rate.

STUDY DESIGN

This was a retrospective cohort study of patients with viable singleton vaginal deliveries after ≥34 weeks gestation at a single perinatal center (2013-2018). The patients were categorized by the mode of delivery: spontaneous vaginal delivery or operative vaginal delivery (forceps or vacuum-assisted). The primary outcome was a composite of maternal infectious morbidity up to 6 weeks after delivery, defined as (1) endometritis, (2) perineal wound morbidity (infection, breakdown, or dehiscence), or (3) culture-proven urinary tract infection. The patient characteristics and outcomes were compared between the groups using appropriate tests. Multivariable models were used to estimate the association between operative vaginal delivery and study outcomes compared with spontaneous vaginal delivery, with adjustment for selected confounders.

RESULTS

Of 14,647 deliveries meeting the inclusion criteria, 732 (5.0%) were operative vaginal deliveries: 354 (48%) forceps and 378 (52%) vacuums. Overall, 210 (1.4%) patients developed the morbidity composite. Patients having an operative vaginal delivery were more likely to be nulliparous, have labor inductions, develop intrapartum chorioamnionitis, receive an episiotomy, and sustain a third- or fourth-degree laceration. After adjusting for confounding factors, no significant association was observed between operative vaginal delivery and composite morbidity (adjusted odds ratio, 1.4 [0.8-2.4]) or any of its individual components. Administration of postpartum antibiotics and documented fever were also similar between groups. There was also no significant association between instrument (forceps vs vacuum) and the maternal infection composite.

CONCLUSION

In this single-center US cohort, operative vaginal delivery was not an independent risk factor for maternal composite postpartum infectious morbidity.

Antibiotic use during repair of obstetrical anal sphincter injury: a quality improvement initiative

OBJECTIVE

To evaluate the effects of a quality improvement initiative regarding the administration of antibiotics at the time of obstetric anal sphincter injury (OASIS) repair.

METHODS

At University of Michigan-a tertiary care center in Ann Arbor, MI, USA, we implemented a quality improvement intervention aimed at administering a single dose of broad-spectrum antibiotics at the time of OASIS repair. Best practice recommendations and reminders were presented to the department. Cefazolin plus metronidazole or clindamycin plus gentamycin were the recommended antibiotics. The effects of this intervention were assessed based on a chart review of deliveries between January 4, 2014 and February 13, 2019, which included patient data both pre-initiative and post-initiative to compare the prevalence of antibiotic use at the time of OASIS repair.

RESULTS

Recommended antibiotic use increased from 0.3% (1/372) pre-initiative to 75.7% (106/140) post-initiative (P < 0.001), and any antibiotic use increased from 6.5% (24/372) to 82.9% (116/140, P < 0.001). The proportion of cases complicated by wound infection/breakdown decreased by 55% after the quality improvement intervention (3.2% pre-intervention vs 1.4% post-intervention, P = 0.22).

CONCLUSION

Following a departmental quality improvement intervention aimed at increasing antibiotic administration at the time of OASIS repair, antibiotic use increased 13-fold. Although underpowered to detect a significant difference in wound complications, our study showed a clinically meaningful decrease in wound infection/breakdown with antibiotic administration.

Risk Factors for Postpartum Maternal Infection Following Spontaneous Vaginal Delivery Complicated by Chorioamnionitis

Objective  Guidelines for the management of chorioamnionitis include intrapartum antibiotics, while postpartum antibiotics after spontaneous vaginal delivery (SVD) are reserved high-risk women. Our objective is to describe the incidence of and risk factors for postpartum infection after SVD complicated by chorioamnionitis. Study Design  This is a retrospective study of SVDs with clinically diagnosed chorioamnionitis at a single center. The primary outcome was a composite of postpartum infection. Women who developed the primary outcome were compared with those who did not using bivariate statistics. Regression models were developed to estimate adjusted odds of outcomes. Results  In this cohort, 346 women underwent SVD complicated by chorioamnionitis. Of these, 23 (6.6%) developed postpartum infections (endometritis n  = 7, urinary tract infection/pyelonephritis n  = 6, sepsis n  = 4, and perineal wound infection n  = 6). Receipt of antibiotics intra- or postpartum did not differ between groups, but women with postpartum infections were more likely to deliver prior to 32 weeks (17.4 vs. 4.9%, p  = 0.04). When controlling for antibiotic use, delivery at < 32 weeks was associated with 3.8-fold increased (95% confidence interval: 1.07-13.7) odds of postpartum infection. Conclusion  Postpartum infections occur in ∼1/15 women delivering vaginally with chorioamnionitis, with those who deliver at < 32 weeks' gestation being at increased risk.

Using the new definition of intraamniotic infection - is there morbidity among the women left out?

Background: Recently, ACOG released updated definitions for intraamniotic infection (IAI): maternal fever (≥38.0 °C) and ≥1 symptom (fetal tachycardia, maternal white blood cell count >15,000/mm³ or purulent discharge). Treatment was no longer recommended for women with fever <39.0 °C plus maternal tachycardia or fundal tenderness (previous criteria). The objective of this study was to compare postpartum infectious morbidity among women meeting previous criteria (but not the new IAI criteria) to women meeting new IAI criteria.Methods: Retrospective cohort of women delivering vaginally at a single academic center. Demographics, antepartum and intrapartum characteristics of women who met diagnostic criteria for chorioamnionitis (previous criteria) compared to those who met IAI criteria using bivariate statistics. The primary outcome was a composite of postpartum infection, including: endometritis, perineal infection, sepsis, urinary tract infection, pyelonephritis. Backward-stepwise elimination used to estimate odds of primary outcome.Results: Of 229 women who met previous IAI criteria, 51 (22.3%) did not meet new IAI criteria. Women no longer meeting IAI criteria were younger (25 versus 27 years, p = .02), more likely to have gestational hypertension (16.0 versus 3.4%, p < .01), and less likely to have third or fourth degree lacerations (2.0 versus 13.4%, p = .02). No difference in antibiotic receipt was observed. Postpartum infection occurred in 16/229 (7.0%) women overall; five (9.8%) in those not meeting new IAI criteria, and 11 (6.2%) meeting new IAI criteria. After adjusting for confounders, there was no difference in odds of postpartum infection (aOR 1.65, 95% CI 0.55-4.99).Conclusions/implications: Among women who met old ACOG criteria for IAI, but not the new criteria, postpartum infection occurred in nearly 10%. This number could be higher if these women were not treated with antibiotics.

Postpartum Group A Streptococcus Case Series: Reach Out to Infection Prevention!

A series of postpartum Streptococcus pyogenes infections prompted an investigation to rule out potential transmission by a health care worker. None of the hospital staff screened were colonized. All isolates were determined to be unrelated by molecular methods, including whole-genome sequencing. Thus, nosocomial transmission was considered unlikely.

Postpartum infection in relation to maternal characteristics, obstetric interventions and complications

The purpose was to evaluate the association between maternal characteristics, obstetrical interventions/complications and postpartum wound infections (WI), urinary tract infection (UTI) and endometritis. Furthermore, this study aimed to determine the time from delivery to onset of infections after discharge from the hospital. Three large Swedish Medical Health Registers were scrutinized for the period 2005-2012. A total of 582,576 women had 795,072 deliveries. Women with diagnosis codes for WIs, UTIs or endometritis, from delivery to 8 weeks postpartum, were compared to non-infected women. Adjusted odds ratios (OR) and 95% confidence intervals (CI) were estimated. Increasing age and body mass index (BMI) were both associated with increasing prevalence of postpartum infections. WIs were most strongly associated with cesarean section (CS) (OR 17.2; 95%CI 16.1-18.3), 3rd and 4th degree tears (OR 10.7%; 95%CI 9.80-11.9) and episiotomy (OR 10.2; 95%CI 8.94-11.5). Endometritis was associated with anemia (OR 3.16; 95%CI 3.01-3.31) and manual placental removal (OR 2.72; 95%CI 2.51-2.95). UTI was associated with emergency CS (OR 3.46; 95%CI 3.07-3.89) and instrumental delivery (OR 3.70; 95%CI 3.29-4.16). For women discharged from the delivery hospital the peak occurrence of UTI was 6 days postpartum, while for WIs and endometritis it was 7 days postpartum.

A model to predict risk of postpartum infection after Caesarean delivery

PURPOSE

The purpose of this study is to build and validate a statistical model to predict infection after caesarean delivery (CD).

METHODS

Patient and surgical variables within 30 d of CD were collected on 2419 women. Postpartum infection included surgical site infection, urinary tract infection, endomyometritis and pneumonia. The data were split into model development and internal validation (1 January-31 August; N = 1641) and temporal validation subsets (1 September-31 December; N = 778). Logistic regression models were fit to the data with concordance index and calibration curves used to assess accuracy. Internal validation was performed with bootstrapping correcting for bias.

RESULTS

Postoperative infection occurred in 8% (95% CI 7.3-9.9), with 5% meeting CDC criteria for surgical site infections (SSI) (95% CI 4.1-5.8). Eight variables were predictive for infection: increasing BMI, higher number of prior Caesarean deliveries, emergent Caesarean delivery, Caesarean for failure to progress, skin closure using stainless steel staples, chorioamnionitis, maternal asthma and lower gestational age. The model discriminated between women with and without infection on internal validation (concordance index = 0.71 95% CI 0.67-0.76) and temporal validation (concordance index = 0.70, 95% CI 0.62, 0.78).

CONCLUSIONS

Our model accurately predicts risk of infection after CD. Identification of patients at risk for postoperative infection allows for individualized patient care and counseling.

Does uterine gauze packing increase the risk of puerperal morbidity in the management of postpartum hemorrhage during caesarean section: a retrospective cohort study

BACKGROUND

To compare the outcomes especially the puerperal morbidity of uterine gauze packing (UGP) with those of uterine balloon tamponade (UBT) in the management of postpartum hemorrhage (PPH) during caesarean section (c-section).

METHODS

It was considered success as no requirement for either a further therapy or hysterectomy for PPH. The postpartum infection risk was pragmatically measured as puerperal morbidity.

RESULTS

The identified PPH subjects were subdivided into two groups for comparison, in which UGP or UBT was used as second-line therapy for women undergoing c-sections between January 2010 and September 2014. Of the 318 c-section subjects initially treated by basic managements for expected PPH, 99 cases underwent UGP and 66 UBT as the second-line therapies to stop persistent bleeding. The success rates of the UGP and UBT groups were 90.91 and 87.88%, respectively. Only one patient in UBT group resorted to hysterectomy. The respective rates of puerperal morbidity were 10.10 and 13.64%, with risk ratio of 0.74 (95% CI: 0.32, 1.72). There were no significant differences between the two groups even after the adjustment for potential confounding factors.

CONCLUSION

UGP appears to be effective in treating PPH during c-section without an observed increase in the risk of potential postpartum infection when compared with UBT. UGP could be recommended as routine for patients who are not responding to conventional basic therapies in addressing PPH, along with the provision of appropriate training.

Life-threatening necrotizing myometritis, due to Group A streptococcus - still a life-threatening condition

Puerperal infection with Group A streptococcus (GAS) can present with few symptoms and rapidly progress to a life-threatening condition. Often, the infection can be treated with antibiotics. Delay in diagnosis increases risk of sepsis, multiorgan failure, and death. GAS infection is a differential diagnose for all postpartum women with unexplained symptoms.

Deconstruction junction: how to separate the good evidence from the bad (from the ugly)

In this column, the author reprises recent selections from the Lamaze International research blog, Science & Sensibility. Each selection discusses a new study that demonstrates the need to look closely at research articles to avoid being misled. Examples include new research on the effectiveness of intrapartum antibiotics for preventing early onset Group B streptococcal disease in newborns, a recent study on the incidence of infection after cesarean surgery and vaginal birth, and a new study demonstrating long-term benefits of skin-to-skin contact between the mother and infant after birth.