Antibiotic prophylaxis for women undergoing caesarean section and infant health

Long-term impact of pre-incision antibiotics on children born by caesarean section: a longitudinal study based on UK electronic health records

BACKGROUND

Since changes in the national guidance in 2011, prophylactic antibiotics for women undergoing caesarean section are recommended prior to skin incision, rather than after the baby's umbilical cord has been clamped. Evidence from randomised controlled trials conducted outside the UK has shown that this reduces maternal infectious morbidity; however, the prophylactic antibiotics also cross the placenta, meaning that babies are exposed to them around the time of birth. Antibiotics are known to affect the gut microbiota of the babies, but the long-term effects of exposure to high-dose broad-spectrum antibiotics around the time of birth on allergy and immune-related diseases are unknown.

OBJECTIVES

We aimed to examine whether or not in-utero exposure to antibiotics immediately prior to birth compared with no pre-incisional antibiotic exposure increases the risk of (1) asthma and (2) eczema in children born by caesarean section.

DESIGN

This was a controlled interrupted time series study.

SETTING

The study took place in primary and secondary care.

PARTICIPANTS

Children born in the UK during 2006-18 delivered by caesarean section were compared with a control cohort delivered vaginally.

INTERVENTIONS

In-utero exposure to antibiotics immediately prior to birth.

MAIN OUTCOME MEASURES

Asthma and eczema in children in the first 5 years of life. Additional secondary outcomes, including other allergy-related conditions, autoimmune diseases, infections, other immune system-related diseases and neurodevelopmental conditions, were also assessed.

DATA SOURCES

The Health Improvement Network (THIN) and the Clinical Practice Research Datalink (CPRD) primary care databases and the Hospital Episode Statistics (HES) database. Previously published linkage strategies were adapted to link anonymised data on mothers and babies in these databases. Duplicate practices contributing to both THIN and the CPRD databases were removed to create a THIN-CPRD data set.

RESULTS

In the THIN-CPRD and HES data sets, records of 515,945 and 3,945,351 mother-baby pairs were analysed, respectively. The risk of asthma was not significantly higher in children born by caesarean section exposed to pre-incision antibiotics than in children whose mothers received post-cord clamping antibiotics, with an incidence rate ratio of 0.91 (95% confidence interval 0.78 to 1.05) for diagnosis of asthma in primary care and an incidence rate ratio of 1.05 (95% confidence interval 0.99 to 1.11) for asthma resulting in a hospital admission. We also did not find an increased risk of eczema, with an incidence rate ratio of 0.98 (95% confidence interval 0.94 to1.03) and an incidence rate ratio of 0.96 (95% confidence interval 0.71 to 1.29) for diagnosis in primary care and hospital admissions, respectively.

LIMITATIONS

It was not possible to ascertain the exposure to pre-incision antibiotics at an individual level. The maximum follow-up of children was 5 years.

CONCLUSIONS

There was no evidence that the policy change from post-cord clamping to pre-incision prophylactic antibiotics for caesarean sections during 2006-18 had an impact on the incidence of asthma and eczema in early childhood in the UK.

FUTURE WORK

There is a need for further research to investigate if pre-incision antibiotics have any impact on developing asthma and other allergy and immune-related conditions in older children.

STUDY REGISTRATION

This study is registered as researchregistry3736.

FUNDING

This project was funded by the National Institute for Health and Care Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 26, No. 30. See the NIHR Journals Library website for further project information.

Evidence for causal associations between prenatal and postnatal antibiotic exposure and asthma in children, England

BACKGROUND

Higher risks of asthma have been observed in children with prenatal exposure to antibiotics and during early life compared with those who have not. However, the causality of such associations is unclear.

OBJECTIVE

To assess whether exposure to antibiotics in early life had a causal effect in increasing the risk of asthma in children diagnosed at 5-8 years of life, and the impact in the target population.

METHODS

Data were from electronic health records and questionnaires for children and their mothers in the Born in Bradford birth cohort. Exposure variables were prescriptions of systemic antibiotics to the mother during pregnancy (prenatal) and to the children at 0-24 months of life (postnatal). We assessed the association in 12,476 children with several approaches to deal with different sources of bias (triangulation): the interactions with mother's ethnicity, mode of delivery, and between prenatal and postnatal exposures; dose-response; and estimated the population attributable risk.

RESULTS

There was an association between prenatal exposure at 7-27 days before the child's birth and asthma (adjusted OR = 1.40; 1.05, 1.87), but no association with the negative control exposure (before pregnancy) (adjusted OR = 0.99 (0.88, 1.12)). For postnatal exposure, the adjusted OR was 2.00 (1.71, 2.34), and for sibling analysis, it was 1.99 (1.00, 3.93). For postnatal exposure, the risk of asthma increased with the number of prescriptions. The observed effect of both exposures was lower among children with mothers of Pakistani ethnicity, but inconclusive (p > .25). The interaction between prenatal and postnatal exposures was also inconclusive (p = .287). The population attributable risk of postnatal exposure for asthma was 4.6% (0.1% for prenatal).

CONCLUSIONS

We conclude that the associations between both late-pregnancy prenatal exposure to antibiotics and postnatal exposure to antibiotics and an increased risk of asthma are plausible and consistent with a causal effect.

The impact of Caesarean section on the infant gut microbiome

AIM

Description of the impact of caesarean section on the infant gut microbiome, infant health and solutions to restore the dysbiosis.

METHODS

We searched PubMed and Google Scholar for relevant articles. Only articles published in English were selected. Separate searches were performed for each topic. We selected 60 articles published between 1999 and 2019 by extracting subject headings and key words of interest for this topic.

RESULTS

Caesarean section is an obstetrical procedure that is increasing in prevalence worldwide. On top of the maternal and neonatal risks that this procedure carries, it also induces a dysbiosis of the infant intestinal microbiome possibly challenging the health outcome for the infant. Antibiotics administered during Caesarean deliveries contribute to the development of the gut microbiome. Nonetheless, breastfeeding and several interventions such as vaginal seeding and supplementation with probiotics, prebiotics and synbiotics may contribute to the restoration of the dysbiosis.

CONCLUSION

Caesarean section is associated with the development of an imbalance of the infant gut microbiome. Long-term consequences of this imbalance are debated. Besides breastfeeding, other strategies to restore this dysbiosis need further studies before they can be recommended.

Long-term impact of giving antibiotics before skin incision versus after cord clamping on children born by caesarean section: protocol for a longitudinal study based on UK electronic health records

INTRODUCTION

In the UK, about a quarter of women give birth by caesarean section (CS) and are offered prophylactic broad-spectrum antibiotics to reduce the risk of maternal postpartum infection. In 2011, national guidance was changed from recommending antibiotics after the umbilical cord was cut to giving antibiotics prior to skin incision based on evidence that earlier administration reduces maternal infectious morbidity. Although antibiotics cross the placenta, there are no known short-term harms to the baby. This study aims to address the research gap on longer term impact of these antibiotics on child health.

METHODS AND ANALYSIS

A controlled interrupted time series study will use anonymised mother-baby linked routine electronic health records for children born during 2006-2018 recorded in UK primary care (The Health Improvement Network, THIN and Clinical Practice Research Datalink, CPRD) and secondary care (Hospital Episode Statistics, HES) databases. The primary outcomes of interest are asthma and eczema, two common allergy-related diseases in childhood. In-utero exposure to antibiotics immediately prior to CS will be compared with no exposure when given after cord clamping. The risk of outcomes in children delivered by CS will also be compared with a control cohort delivered vaginally to account for time effects. We will use all available data from THIN, CPRD and HES with estimated power of 80% and 90% to detect relative increase in risk of asthma of 16% and 18%, respectively at the 5% significance level.

ETHICS AND DISSEMINATION

Ethical approval has been obtained from the University of Birmingham Ethical Review Committee with scientific approvals obtained from the independent scientific advisory committees from the Medicines and Healthcare products Regulatory Agency for CPRD and the data provider, IQVIA for THIN. The results will be published in peer-reviewed journals, presented at national and international conferences and disseminated to stakeholders.

Reducing post-caesarean delivery surgical site infections: a narrative review

Surgical site infection complicates 1-10% of caesarean deliveries. With the rate of caesarean delivery increasing, it is important to identify effective measures of preventing surgical site infection and to consider their impact on maternal and neonatal outcomes. Compelling evidence supports the use of prophylactic antibiotics, prior to skin incision, to reduce surgical site infection. However, there remain international variations in terms of the recommended agent, dose and body weight-adjusted dosing. Advances in wound dressings are an evolving area of interest and surgical technique can influence outcomes. This narrative review explores pharmacological and non-pharmacological methods of preventing surgical site infection following caesarean delivery.

Infections complicating cesarean delivery

PURPOSE OF REVIEW

Cesarean sections are common surgical procedures performed in a healthy population and are unique because of a relatively high rate of postoperative infection. There have been many important advances in understanding the pathogenesis of infection and evaluation of interventions to prevent post cesarean section infections in the last few years. Our purpose in this review is to analyze these new data, discuss unanswered questions, and propose changes in standard of care.

RECENT FINDINGS

Wound closure techniques including subcuticular sutures and subcutaneous suturing have been shown to be effective at reducing surgical site infections. Wound dressings including negative pressure dressings likely do not decrease infection rates. The type, timing, and duration of preoperative prophylactic antibiotics, including adjunctive azithromycin for laboring women and multidose antibiotics in obese women, have also yielded mixed results. Our understanding of normal uterine microbiome and the impact of intrapartum antibiotics on the newborn is emerging.

SUMMARY

The pathogenesis of surgical site infections after Cesarean section is complex and multifactorial. Many interventions to reduce infections have been studied with varying degrees of effectiveness. Despite advances in the area, important questions remain unanswered.

National survey of obstetric anaesthesia clinical practices in the republic of Austria

BACKGROUND

The aim of this study was to describe the current obstetric anaesthetic practices in Austria by performing a comprehensive questionnaire survey.

METHODS

A questionnaire was sent via email to key anaesthesiologists from obstetric anaesthesia departments of 81 hospitals registered at the Austrian Ministry of Health.

RESULTS

Of 81 departments contacted, 65 (80%), covering 84% of annual births in Austria, responded to the 82-question survey. Epidural analgesia was offered universally, at a rate under 30% in 56 (86%) of respondent hospitals. The caesarean section rate was under 30% in 44 (68%) respondent obstetric units. All respondents provided spinal anaesthesia as the primary anaesthetic technique for elective caesarean section. Three (5%) respondents administered long-acting intrathecal morphine and 18 (28%) respondents did not routinely administer any intrathecal opioid. Wound infiltration for acute postoperative pain control was practiced in two (3%) respondent units. A transversus abdominis plane block was offered as rescue analgesia in 14 (22%) departments. Spinal hypotension was treated using a prophylactic phenylephrine infusion in two (3%) respondent hospitals. Prophylactic antibiotics were administered prior to skin incision by 31 (48%) respondents.

CONCLUSION

This survey reveals that obstetric anaesthetic practices in Austria differ in part from current European and American guidelines. Findings will direct the national workforce on obstetric anaesthesia that aims to introduce into Austria practice guidelines, based on international collaborations and guideline recommendations.