Trends in Indigenous and non-Indigenous caesarean section births in the Northern Territory of Australia, 1986-2012: a total population-based study

Pregnancy Outcomes of Different Endometrial Preparation in Patients With a History of Cesarean Section

OBJECTIVE

To investigate the efficacies of three cycle regimens in women receiving frozen embryo transfer with a history of cesarean section: natural cycle treatment, hormone replacement therapy and treatment with gonadotropin-releasing hormone agonist.

DESIGN

Retrospective cohort study.

METHODS

patients (N = 6,159) with a history of caesarean section who fulfilled the inclusion criteria were enrolled in the study from January 2014 to December 2019 at the CITIC-Xiangya Hospital of Reproduction and Genetics. Reproductive outcomes of patients in the natural cycle (n = 4,306) versus hormone replacement therapy (n = 1,007) versus gonadotropin-releasing hormone agonist + hormone replacement therapy groups (n = 846) were compared. Continuous data were analyzed using Student's t-test, and categorical variables were analyzed using the χ2 test. Multivariable logistic regression was used to evaluate the possible relationships between the types of endometrial preparation and pregnancy outcomes after adjusting for confounding factors.

RESULTS

The unadjusted odds of the miscarriage rate of singleton pregnancies were significantly higher in the hormone replacement therapy compared with the natural cycle (25.5% versus 20.4%, respectively). After adjusting for possible confounding factors, the early miscarriage rate and the miscarriage rate of singleton pregnancies remained significantly higher in the hormone replacement therapy than the natural cycle. The clinical pregnancy rates in the natural cycle, hormone replacement therapy and gonadotropin- releasing hormone agonist + hormone replacement therapy of women with a history of cesarean section was 48.8%, 48% and 47.1%, respectively, and the live birth rates were 37%, 34.1% and 35.7%, respectively.

CONCLUSIONS

In women undergoing frozen embryo transfer with a history of cesarean section, hormone replacement therapy for endometrial preparation was associated with a higher early miscarriage rate, albeit after statistical adjustment for confounding factors. However, the risk observed was little and did not influence the overall reproductive performances.

Effect of a prior cesarean delivery on pregnancy outcomes of frozen-thawed embryo transfer: A retrospective cohort study in a freeze-all setting

INTRODUCTION

The association between the mode of previous delivery and subsequent success of assisted reproductive treatment has been poorly understood. By mitigating the detrimental effect of supraphysiologic estradiol levels on endometrial receptivity, a freeze-all strategy provides a novel model to investigate the sole impact of a prior cesarean delivery (CD) on embryo transfer outcomes.

MATERIAL AND METHODS

This single-center retrospective cohort study included 2660 patients who underwent their first frozen-thawed embryo transfer cycles after a freeze-all policy from January 2013 to December 2018. Patients with a history of live birth by CD were assigned to the CD group, and those with only vaginal delivery (VD) were categorized into the VD group. The primary outcome measure was live birth. Baseline characteristics of the two groups were balanced by propensity score matching in a ratio of 1:1. Univariate and multivariate logistic regression analyses were performed using the after-matching data.

RESULTS

Compared with the VD group, the rates of clinical pregnancy (38.3% vs 44.5%; P = .005) and live birth (27.5% vs 33.4%; P = .003) were significantly lower in women with a history of CD. When adjusted for a number of major confounding factors, the negative association between a prior CD and frozen-thawed embryo transfer success was maintained, with the adjusted odds ratio (OR) being 0.80 (95% CI 0.66-0.96) and 0.78 (95% CI 0.63-0.95) for clinical pregnancy and live birth, respectively. Furthermore, a CD history conferred a marginally increased risk of early miscarriage (crude OR 1.48, 95% CI 1.04-2.11; adjusted OR 1.47, 95% CI 1.01-2.14), whereas the odds of multiple and ectopic pregnancy did not show significant differences before and after adjustment.

CONCLUSIONS

A prior CD was associated with a decreased chance of live birth and an increased risk of early miscarriage in frozen-thawed embryo transfer cycles.

Evidence of overuse? Patterns of obstetric interventions during labour and birth among Australian mothers

Background

There is global concern for the overuse of obstetric interventions during labour and birth. Of particular concern is the increasing amount of mothers and babies experiencing morbidity and mortality associated with caesarean section compared to vaginal birth. In high-income settings, emerging evidence suggests that overuse of obstetric intervention is more prevalent among wealthier mothers with no medical need of it. In Australia, the rates of caesarean section and other obstetric interventions are rising. These rising rates of intervention have been mirrored by a decreasing rate of unassisted non-instrumental vaginal deliveries. In the context of rising global concern about rising caesarean section rates and the known health effects of caesarean section on mothers and children, we aim to better characterise the use of obstetric intervention in the state of Queensland, Australia by examining the characteristics of mothers receiving obstetric intervention. Identifying whether there is overuse of obstetric interventions within a population is critical to improving the quality, value and appropriateness of maternity care.

Methods

The association between demographic characteristics (at birth) and birth delivery type were compared with chi-square. The percentage of mothers based on their socioeconomic characteristics were reported and differences in percentages of obstetric interventions were compared. Multivariate analysis was undertaken using multiple logistic regression to assess the likelihood of receiving obstetric intervention and having a vaginal (non-instrumental) delivery after accounting for key clinical characteristics.

Results

Indigenous mothers, mothers in major cities and mothers in the wealthiest quintile all had higher percentages of all obstetric interventions and had the lowest percentages of unassisted (non-instrumental) vaginal births. These differences remained even after adjusting for other key sociodemographic and clinical characteristics.

Conclusions

Differences in obstetric practice exist between economic, ethnic and geographical groups of mothers that are not attributable to medical or lifestyle risk factors. These differences may reflect health system, organisational and structural conditions and therefore, a better understanding of the non-clinical factors that influence the supply and demand of obstetric interventions is required.

Anaemia in early childhood among Aboriginal and Torres Strait Islander children of Far North Queensland: a retrospective cohort study

OBJECTIVE

Early childhood anaemia affects health and neurodevelopment. This study describes anaemia among Aboriginal and Torres Strait Islander children of Far North Queensland.

METHODS

This retrospective cohort study used health information for children born between 2006 and 2010 and their mothers. We describe the incidence of early childhood anaemia and compare characteristics of children and mothers where the child had anaemia with characteristics of children and mothers where the child did not have anaemia using bivariate and multivariable analysis, by complete case (CC) and with multiple imputed (MI) data.

RESULTS

Among these (n=708) Aboriginal and Torres Strait Islander children of Far North Queensland, 61.3% (95%CI 57.7%, 64.9%) became anaemic between the ages of six and 23 months. Multivariable analysis showed a lower incidence of anaemia among girls (CC/MI p<0.001) and among children of Torres Strait Islander mothers or both Aboriginal and Torres Strait Islander mothers (CC/MI p<0.001) compared to children of Aboriginal mothers. A higher incidence of anaemia was seen among children of mothers with parity three or more (CC/MI p<0.001); children born by caesarean section (CC/MI p<0.001); and children with rapid early growth (CC/MI p<0.001).

CONCLUSION

Early childhood anaemia is common among Aboriginal and Torres Strait Islander children of Far North Queensland. Poor nutrition, particularly iron deficiency, and frequent infections are likely causes. Implications for public health: Prevention of early childhood anaemia in 'Close the Gap' initiatives would benefit the Aboriginal and Torres Strait Islander children of Far North Queensland - and elsewhere in northern Australia.

A retrospective population-based study of induction of labour trends and associated factors among aboriginal and non-aboriginal mothers in the northern territory between 2001 and 2012

Background

Induction of labour (IOL) has become more common among many populations, but the trends and drivers of IOL in the Northern Territory (NT) of Australia are not known. This study investigated trends in IOL and associated factors among NT Aboriginal and non-Aboriginal mothers between 2001 and 2012.

Methods

A retrospective analysis of all NT resident women who birthed in the NT between 2001 and 2012 at ≥32 weeks gestation. Demographic, medical and obstetric data were obtained from the NT Midwives’ Collection. The prevalence of IOL was calculated by Aboriginal status and parity of the mother and year of birth. The prevalence of each main indication for induction among women was compared for 2001–2003 and 2010–2012. Linear and logistic regression was used to test for association between predictive factors and IOL in bivariate and multivariate analysis, separately for Aboriginal and non-Aboriginal mothers.

Results

A total of 42,765 eligible births between 2001 and 2012 were included. IOL was less common for Aboriginal than non-Aboriginal mothers in 2001 (18.0 % and 25.1 %, respectively), but increased to be similar to non-Aboriginal mothers in 2012 (22.6 % and 24.8 %, respectively). Aboriginal primiparous mothers demonstrated the greatest increase in IOL. The most common indication for IOL for both groups was post-dates, which changed little over time. Medical and obstetric complications were more common for Aboriginal mothers except late-term pregnancy. Prevalence of diabetes in pregnancy increased considerably among both Aboriginal and non-Aboriginal mothers, but was responsible for only a small proportion of IOLs. Increasing prevalence of risk factors did not explain the increased IOL prevalence for Aboriginal mothers.

Conclusions

IOL is now as common for Aboriginal as non-Aboriginal mothers, though their demographic, medical and obstetric profiles are markedly different. Medical indications did not explain the recent increase in IOL among Aboriginal mothers; changes in maternal or clinical decision-making may have been involved.