The risk of maternal and placental complications in pregnant women with asthma: a systematic review and meta-analysis

Asthma Exacerbation Risk in Pregnancy and Postpartum: Assessing the Impact of Gestational Diabetes Mellitus and Other Key Factors

BACKGROUND

Asthma, affecting approximately 13% of pregnancies worldwide, and gestational diabetes mellitus (GDM), present in approximately 14%, are both associated with adverse maternal and perinatal outcomes. This study aims to address a lack of current knowledge about how GDM affects asthma during pregnancy.

OBJECTIVE

To determine whether GDM is associated with an increased risk of asthma exacerbations during pregnancy and the first year postpartum.

METHODS

This retrospective cohort study analyzed electronic health records of pregnant patients with asthma from 2010 to 2023, excluding those with pre-existing diabetes mellitus or concurrent chronic lung diseases. Asthma exacerbations were defined by the need for an oral corticosteroid prescription. Multivariable logistic regression and zero-inflated Poisson regression were used to adjust for age, race, body mass index (BMI), prepregnancy asthma exacerbation history, and insurance status.

RESULTS

Among 10,985 individuals, 1492 had GDM. Patients with GDM were older with higher BMIs. GDM was associated with increased asthma exacerbation risk during pregnancy (adjusted odds ratio [OR] = 1.36, 95% confidence interval [CI]: 1.10-1.67), but not postpartum. Stratified analyses of 4331 individuals with gestational blood glucose measurement showed that each doubling of blood glucose levels doubled the risk of asthma exacerbations during pregnancy (adjusted OR = 2.02, 95% CI: 1.45-2.81). Other factors associated with asthma exacerbation included prepregnancy asthma exacerbations, older age, and Medicaid coverage.

CONCLUSION

The association between GDM and increased risk of asthma exacerbations underscores the need for early, universal screening and effective interventions to improve blood glucose control in pregnant individuals with pre-existing asthma.

In utero exposure to experimental maternal asthma alters fetal airway development in sheep

The mechanisms linking maternal asthma (MA) exposure in utero and subsequent risk of asthma in childhood are not fully understood. Pathological airway remodelling, including reticular basement membrane thickening, has been reported in infants and children who go on to develop asthma later in childhood. This suggests altered airway development before birth as a mechanism underlying increased risk of asthma in children exposed in utero to MA. We hypothesised that in utero MA exposure would reduce airway diameter and increase airway-associated smooth muscle area and reticular basement membrane thickness in neonatal offspring. Experimental MA was induced by maternal sensitisation followed by airway challenges with house dust mite before and during pregnancy. Lambs from control (n = 16) or MA (n = 26) ewes were delivered at ∼140 days gestation (term = 150 days), ventilated for 45 min, then humanely killed. Left lungs were inflation-fixed, and cross-sections of generation 2-5 airways were collected. Airway sections were stained with Haematoxylin and Eosin, Masson's Trichrome and Gordon and Sweet's histological stains for morphological analysis. Lamb body and lung weights were similar between groups (P > 0.5 and P > 0.7, respectively). Lambs that were exposed to MA had narrower airway diameters (P = 0.019) and thinner reticular basement membrane (P = 0.016) but similar airway-associated smooth muscle area (P = 0.152) compared with unexposed control lambs. Our results demonstrate a potential mechanism for increased risk of asthma in children of mothers with asthma, independent of genetic risk or behavioural changes during pregnancy.

Maternal asthma during pregnancy and the likelihood of neurodevelopmental disorders in offspring

INTRODUCTION

Asthma is the most common chronic disease during pregnancy. Maternal asthma has been associated with a multitude of unwanted pregnancy outcomes, in some studies also with neurodevelopmental disorders. Here we investigated associations between maternal asthma and neurodevelopmental disorders.

MATERIAL AND METHODS

We studied a retrospective population-based cohort of 1 271 439 mother-child pairs from singleton live births in Finland between the years 1996-2018. We used multiple high-cover registers for data collection. Adjusted unconditional Cox regression models were used to investigate associations between maternal asthma, asthma medication used during pregnancy, and offspring's neurodevelopmental disorder diagnoses.

RESULTS

We identified 106 163 mother-child pairs affected by maternal asthma. We found that maternal asthma was associated with offspring neurodevelopmental disorders, but the differences in absolute prevalence between the control and exposure groups were small. Attention-deficit hyperactivity disorder (ADHD) was found in 4114 (3.9%) offspring with maternal asthma and in 32 122 (3.0%) controls (adjusted hazard ratio (HR): 1.49; 95% CI 1.44-1.54); autism in 1617 (1.5%) offspring vs 13 701 (1.3%) controls (HR: 1.33; 95% CI 1.26-1.40); motor-developmental disorder in 1569 (1.5%) offspring vs 12 147 (1.1%) controls (HR: 1.37; 95% CI 1.30-1.45); language disorder in 3057 (2.9%) offspring vs 28 421 (2.7%) controls (HR: 1.13; 95% CI 1.08-1.17), learning disabilities in 849 (0.8%) offspring vs 6534 (0.6%) controls (HR: 1.51; 95% CI 1.41-1.62); mixed developmental disorder in 1633 (1.5%) offspring vs 14 434 (1.3%) controls (HR 1.20; 95% CI, 1.14-1.26); and intellectual disability in 908 (0.9%) vs 9155 (0.9%) controls (HR: 1.12; 95% CI 1.04-1.20). No substantial differences were found between allergic and non-allergic asthma phenotypes, and neither allergic tendency nor respiratory infection was associated with a similar likelihood of neurodevelopmental disorders.

CONCLUSIONS

Maternal asthma and allergic and non-allergic phenotypes showed weak associations with the offspring's neurodevelopmental disorders. The association is concerned especially with learning disabilities, ADHD, motor development, and autism.

Betamethasone improved near-term neonatal lamb lung maturation in experimental maternal asthma

Maternal asthma is associated with increased rates of neonatal lung disease, and fetuses from asthmatic ewes have fewer surfactant-producing cells and lower surfactant-protein B gene (SFTPB) expression than controls. Antenatal betamethasone increases lung surfactant production in preterm babies, and we therefore tested this therapy in experimental maternal asthma. Ewes were sensitised to house dust mite allergen, and an asthmatic phenotype induced by fortnightly allergen lung challenges; controls received saline. Pregnant asthmatic ewes were randomised to receive antenatal saline (asthma) or 12 mg intramuscular betamethasone (asthma+beta) at 138 and 139 days of gestation (term = 150 days). Lambs were delivered by Caesarean section at 140 days of gestation and ventilated for 45 min before tissue collection. Lung function and structure were similar in control lambs (n = 16, 11 ewes) and lambs from asthma ewes (n = 14, 9 ewes). Dynamic lung compliance was higher in lambs from asthma+beta ewes (n = 12, 8 ewes) compared to those from controls (P = 0.003) or asthma ewes (P = 0.008). Lung expression of surfactant protein genes SFTPA (P = 0.048) and SFTPB (P < 0.001), but not SFTPC (P = 0.177) or SFTPD (P = 0.285), was higher in lambs from asthma+beta than those from asthma ewes. Female lambs had higher tidal volume (P = 0.007), dynamic lung compliance (P < 0.001), and SFTPA (P = 0.037) and SFTPB gene expression (P = 0.030) than males. These data suggest that betamethasone stimulates lung maturation and function of near-term neonates, even in the absence of impairment by maternal asthma.

Breathing for Two: Asthma Management, Treatment, and Safety of Pharmacological Therapy during Pregnancy

The primary objectives of asthma management during pregnancy are to achieve adequate symptom control, reduce the risk of acute exacerbations, and maintain normal pulmonary function, all of which contribute to ensuring the health and well-being of both the mother and the baby. The Global Initiative for Asthma (GINA) recommends that pregnant women with asthma continue using asthma medications throughout pregnancy, as the benefits of well-controlled asthma for both the mother and fetus outweigh the potential risks of medication side effects, poorly controlled asthma, and exacerbations. The classification of asthma medications by the US Food and Drug Administration (FDA) into categories A, B, C, D, and X is no longer applied. Instead, the potential benefits and risks of each medication during pregnancy and lactation are considered individually. The use of medications to achieve good asthma control and prevent exacerbations during pregnancy is justified, encompassing inhaled corticosteroids (ICS), some leukotriene receptor antagonists (LTRA), short-acting beta-2 agonists (SABA), long-acting beta-2 agonists (LABA), short-acting muscarinic antagonists (SAMA), long-acting muscarinic antagonists (LAMA), and, recently, biological therapies, even in the absence of definitive safety data during pregnancy.

Non-allergic factors that influence asthma control in pregnancy

INTRODUCTION

Numerous factors may influence the asthma course during pregnancy, potentially elevating the risk of specific pregnancy complications. This study aimed to evaluate non-allergic factors influencing asthma and to assess perinatal outcomes between asthmatic and non-asthmatic pregnancies in the population of the Pomeranian Voivodeship region of Poland.

METHODS

The mixed cohort study was performed with 83 pregnant asthmatic patients aged 18-38 years. The control group consisted of 83 patients without asthma diagnosis or symptoms. A specially designed questionnaire was used to evaluate asthma course and perinatal outcomes. An Asthma Control Test (ACT) adapted for pregnancy was performed on enrollment. Asthma severity was assessed according to GINA guidelines.

RESULTS

In 19 cases (22.80%), patients quit their regular treatment after pregnancy was confirmed. Respiratory tract infection occurred in 23 patients (27.71%) and had been statistically significantly more frequent among patients with partially and uncontrolled asthma (χ2=8.504, p<0.05). No statistically significant difference was found between infection episodes and perinatal complications. The incidence of cesarean section was significantly higher among patients with asthma (χ2=16.37, p<0.01), particularly in patients with severe asthma (χ2=7.07, p<0.05) and uncontrolled asthma (χ2=6.7, p<0.05). Apgar score was statistically significantly lower in patients with severe asthma (χ2=20.37, p<0.05).

CONCLUSIONS

Respiratory tract infections and adequate asthma treatment are the most important modifiable factors in preventing perinatal complications associated with asthma.

Effect of fractional exhaled nitric oxide (FENO)-based asthma management during pregnancy versus usual care on infant development, temperament, sensory function and autism signs

Asthma during pregnancy is associated with a range of adverse perinatal outcomes. It is also linked to increased rates of neurodevelopmental conditions in the offspring. We aimed to assess whether fractional exhaled nitric oxide (FENO)-based asthma management during pregnancy improves child developmental and behavioural outcomes compared to usual care. The Breathing for Life Trial was a randomised controlled trial that compared FENO-based asthma management during pregnancy to usual care. Participants were invited to the developmental follow-up, the Breathing for Life Trial - Infant Development study, which followed up infants at 6 weeks, 6 months and 12 months. The primary outcomes were measured in infants at 12 months using the Bayley-III: Cognitive, Language and Motor composite scores. Secondary outcomes included Bayley-III social-emotional and adaptive behaviour scores, autism likelihood and sensory and temperament outcomes. The exposure of interest was the randomised intervention group. Two hundred and twenty-two infants and their 217 participating mothers were recruited to the follow-up; 107 mothers were in the intervention group and 113 were in the control group. There was no evidence of an intervention effect for the primary outcomes: Bayley-III cognitive (mean = 108.9 control, 108.5 intervention, p = 0.93), language (mean = 95.9 control, 95.6 intervention, p = 0.87) and motor composite scores (mean = 97.2 control, 97.9 intervention, p = 0.25). Mean scores for secondary outcomes were also similar among infants born to control and FENO group mothers, with few results reaching p < 0.05.

CONCLUSION

 In this sample, FENO-guided asthma treatment during pregnancy did not improve infant developmental outcomes in the first year of life.

TRIAL REGISTRATION

ClinicalTrials.gov Identifier: ACTRN12613000202763.

WHAT IS KNOWN

• Maternal asthma during pregnancy has been associated with increased rates of neurodevelopmental conditions in offspring, including intellectual disability and autism.

WHAT IS NEW

• This is the first study to examine how managing asthma during pregnancy via a FENO-guided algorithm or usual care affects infant developmental and behavioural outcomes. While the results of the study showed no impact of the intervention, and therefore do not support the integration of FENO-based management of asthma in antenatal settings for optimal infant development, they do send a positive message about the implications of active asthma management during pregnancy on infant developmental outcomes.

Impact of Asthma Medications During Pregnancy on Asthma Exacerbation, Maternal, and Neonatal Outcomes

BACKGROUND

Asthma affects 5% to 13% of pregnant women, and many require daily pharmacotherapy to achieve asthma control; however, adherence to medication during pregnancy often decreases.

OBJECTIVE

To understand the association between the use of or adherence to asthma medication with asthma exacerbation and maternal/neonatal outcomes.

METHODS

Using linked population-based administrative databases from Alberta, Canada (2012-2018), pregnant women with asthma were categorized based on asthma medication use 1 year before pregnancy: short-acting β-agonists (SABA), inhaled corticosteroids (ICS), and ICS with long-acting β-agonists (ICS+LABA). Women on ICS+LABA were grouped by trajectory of adherence during pregnancy using group-based trajectory modeling. Logistic regressions were used to estimate the associations between the use of or trajectories of adherence to asthma medication during pregnancy with asthma exacerbation and maternal/neonatal outcomes.

RESULTS

Overall, 13,509 of 238,751 (5.7%) pregnant women had asthma before pregnancy (SABA: 24.7%; ICS: 12.5%; ICS+LABA: 25.1%; none: 36.1%). The use of SABA (adjusted odds ratio [aOR]: 1.79, 95% confidence interval [CI]: 1.21, 2.64), ICS (aOR: 3.37, 95% CI: 2.10, 5.39), and ICS+LABA (aOR: 3.64, 95% CI: 2.57, 5.17) had greater odds of disease exacerbation than no asthma medication during pregnancy. ICS+LABA adherence groups during pregnancy included low (79.8%), moderate-to-decreasing (14.0%), and moderate-to-increasing (6.2%). The moderate-to-decreasing (aOR: 1.45, 95% CI: 1.14, 1.84) and moderate-to-increasing (aOR: 2.06, 95% CI: 1.50, 2.83) adherence groups had greater odds of disease exacerbation than the low adherence group. ICS use during pregnancy decreased odds of preterm birth (aOR: 0.62; 95% CI: 0.39, 0.99) and neonatal intensive care unit admission (aOR: 0.66; 95% CI: 0.45, 0.97). Other group comparisons were not statistically significant.

CONCLUSIONS

Our study shows the importance of continuing asthma maintenance medication during pregnancy to improve outcomes. Future research should study the postpartum and long-term outcomes with asthma medication during pregnancy.

Preclinical models of maternal asthma and progeny outcomes: a scoping review

There is an increased risk of adverse perinatal outcomes in the ∼17% of women with asthma during pregnancy. The mechanisms linking maternal asthma and adverse outcomes are largely unknown, but reflect joint effects of genetics and prenatal exposure to maternal asthma. Animal models are essential to understand the underlying mechanisms independent of genetics and comorbidities, and enable safe testing of interventions. This scoping review aimed to explore the methodology, phenotype, characteristics, outcomes and quality of published studies using preclinical maternal asthma models. MEDLINE (PubMed), Embase (Elsevier) and Web of Science were systematically searched using previously validated search strings for maternal asthma and for animal models. Two reviewers independently screened titles and abstracts, full texts, and then extracted and assessed the quality of each study using the Animal Research: Reporting of In Vivo Experiments (ARRIVE) 2.0 guidelines. Out of 3618 studies identified, 39 were eligible for extraction. Most studies were in rodents (86%) and all were models of allergic asthma. Maternal and progeny outcomes included airway hyperresponsiveness, airway resistance, inflammation, lung immune cells, lung structure and serum immunoglobulins and cytokines. Experimental design (100%), procedural details (97%) and rationale (100%) were most often reported. Conversely, data exclusion (21%), blinding (18%) and adverse events (8%) were reported in a minority of studies. Species differences in physiology and timing of development, the use of allergens not relevant to humans and a lack of comparable outcome measures may impede clinical translation. Future studies exploring models of maternal asthma should adhere to the minimum core outcomes set presented in this review.

Factors and outcomes for placental anomalies: An umbrella review of systematic reviews and meta-analyses

Background

Placental anomalies, including placenta previa (PP), placenta accreta spectrum disorders (PAS), and vase previa (VP), are associated with several adverse foetal-neonatal and maternal complications. However, there is still a lack of robust evidence on the pathogenesis and adverse outcomes of the diseases. Through this umbrella review, we aimed to systematically review existing meta-analyses exploring the factors and outcomes for pregnancy women with placental anomalies.

Methods

We searched PubMed, Embase, Web of Science, and the Cochrane Library from inception to February 2023. We used AMSTAR 2 to assess the quality of the reviews and estimated the pooled risk and 95% confidence intervals (CIs) for each meta-analysis.

Results

We included 34 meta-analyses and extracted 55 factors (27 for PP, 22 for PAS, and 6 for VP) and 16 outcomes (12 for PP, and 4 for VP) to assess their credibility. Seven factors (maternal cocaine use (for PP), uterine leiomyoma (for PP), prior abortion (spontaneous) (PP), threatened miscarriage (PP), maternal obesity (PP), maternal smoking (PAS), male foetus (PAS)) had high epidemiological evidence. Twelve factors and six outcomes had moderate epidemiological evidence. Twenty-two factors and eight outcomes showed significant association, but with weak credibility.

Conclusions

We found varying levels of evidence for placental anomalies of different factors and outcomes in this umbrella review.

Registration

PROSPERO: CRD42022300160.

Managing Asthma During Pregnancy and the Postpartum Period

Asthma is one of the most common chronic diseases in pregnancy and is associated with adverse perinatal outcomes. Asthma symptoms worsen in approximately 40% of women, and exacerbations requiring medical intervention occur in at least 20% of women. Factors associated with exacerbation and worsening asthma include multiparity, obesity, Black race, exacerbations before pregnancy, and poor asthma control. Exacerbations are associated with further increased risks for poor perinatal outcomes, including low birth weight, preterm birth, and small for gestational age (SGA) status, as well as an increase in the development of asthma in early childhood. Common medications used for asthma, including short-acting β-agonists and inhaled corticosteroids, are considered safe to use in pregnancy. Whereas guidelines generally suggest traditional step therapy for managing asthma in pregnancy, there are alternative models of care and management approaches that may be effective in pregnancy, but require more research. These include single-inhaler maintenance and reliever therapy, treatment adjustment with FeNO, treatable traits personalized medicine approaches, and telemedicine. Little is known about changes to asthma in the postpartum period. However, low adherence to medication and the potential effects of postpartum depression on asthma exacerbation risk warrant further research.

Trajectory of prenatal anxiety and depression and its association with fetal growth development

BACKGROUND

The stability of anxiety and depression during pregnancy and the impact on women and offspring has been recognized, yet the distinction of impact between them remains unclear. The aim of this study was to investigate the trajectory of prenatal anxiety and depression and their coexistence, as well as to examine the potential variations in pregnancy outcomes and fetal/neonatal growth development.

METHOD

At baseline (11-13+6 weeks), women were recruited and subsequently monitored in the second (16-20+6 weeks) and third (28-31+6 weeks) trimesters. Anxiety and depression were measured using the Hospital Anxiety and Depression Scale. In the second (16-20+6 weeks), third (28-31+6 weeks), and prenatal period (37-40+6 weeks), fetal growth was assessed by ultrasound scans. The joint trajectory model was used to determine the trajectory groups of depressive/anxiety dominant or coexistence. Comparisons of fetal/neonatal growth between groups were conducted using analysis of covariance and a multilevel model.

RESULT

A total of 457 pregnant women were finally included. Four trajectory groups were identified: none-negative emotion (n = 190, 41.6 %), anxiety dominant (n = 195, 42.6 %), depression dominant (n = 33, 7.2 %), and anxiety and depression coexistence (n = 39, 8.6 %). There were significant differences in the antenatal abdominal circumference (335.44 vs 333.92 vs 330.82 vs 325.13 mm, p = 0.007) of fetuses and the birth length (50.14 vs 50.03 vs 49.91 vs 49.18, p = 0.008) of newborns among four groups, showing a clear decreasing trend. Anxiety and depression coexistence displayed a notable and statistically significant difference when compared to the other groups and had a lower increase of fetal abdominal circumference (β = -8.91, 95%CI: -16.15, -1.67, p = 0.016) after controlling for confounding factors. Anxiety and depression dominant groups found no difference in fetal/neonatal growth.

CONCLUSIONS

The more severe the negative emotional state of mothers, the more restricted their offspring's development, especially in terms of fetal abdominal circumference and birth length. The impact of anxiety or depressive symptoms does not show a pronounced difference. However, what is noteworthy is the tendency and evident impact on offspring development when anxiety and depression coexistence work synergistically. As a result, healthcare professionals should place greater emphasis on addressing anxiety and depression in expectant mothers, particularly among those experiencing anxiety and depression coexisting symptoms.

Preclinical models of maternal asthma and progeny outcomes: a scoping review protocol

OBJECTIVE

This scoping review will describe the methodology, phenotype, and characteristics of maternal asthma models used in preclinical studies and the outcomes that have been measured in the mother and progeny. The review This will identify gaps in knowledge of maternal and progeny outcomes following maternal asthma in pregnancy.

INTRODUCTION

Maternal asthma affects up to 17% of pregnancies worldwide and is associated with adverse perinatal outcomes in mothers and babies, including pre-eclampsia, gestational diabetes, cesarean section, preterm birth, small for gestational age, nursery admission, and neonatal death. While the associations are well established, the mechanisms linking maternal asthma and adverse perinatal outcomes are largely unknown due to the difficulties of human mechanistic studies. The appropriate selection of animal models is vital to understanding the mechanisms underlying associations between human maternal asthma and adverse perinatal outcomes.

INCLUSION CRITERIA

This review will include primary studies published in English where outcomes have been studied in vivo in non-human mammalian species.

METHODS

This review will follow the JBI methodology for scoping reviews. We will search MEDLINE (PubMed), Embase, and Web of Science to identify papers published before the end of 2022. Initial keywords will include pregnancy, gestation, asthma , and wheeze , as well as validated search strings to identify papers that describe animal models. Extracted data will include information on methods used to induce maternal asthma; asthmatic phenotypes and characteristics; and maternal, pregnancy, placental, and progeny outcomes. The characteristics of each study will be presented in summary tables and a core outcome list to assist researchers in developing, reporting, and comparing future animal studies of maternal asthma.

REVIEW REGISTRATION

Open Science Framework osf.io/trwk5.

Treatable traits, combination inhaler therapy and the future of asthma management

The landscape of asthma has considerably changed in the last decade. Effective medications and inhaler devices have been developed and integrated into the asthma pharmacopoeia, but unfortunately, the proportion of uncontrolled patients remains unacceptably high. This is now recognized to be mainly due to the inappropriate use of medications or inhaler devices, heterogeneity of the disease or other factors contributing to the disease. Currently, inhaled corticosteroids (ICS), with or without long-acting beta agonists (LABA), are the cornerstone of asthma management, and recently international guidelines recognized the importance of combination inhaler therapy (ICS/LABA) even in mild asthma. In future, ultra-long-acting personalized medications and smart inhalers will complement combination inhaler therapy in order to effectively addresses issues such as adherence, inhaler technique and polypharmacy (both of drugs and devices). Asthma is now acknowledged as a multifaceted cluster of disorders and the treatment model has evolved from one-size-fits-all to precision medicine approaches such as treatable traits (TTs, defined as measurable and treatable clinically important factors) which encourages the quality use of medications and identification and management of all underlying behavioural and biological treatable risk factors. TT requires research and validation in a clinical context and the implementation strategies and efficacy in various settings (primary/secondary/tertiary care, low-middle income countries) and populations (mild/moderate/severe asthma) are currently evolving. Combination inhaler therapy and the TTs approach are complementary treatment approaches. This review examines the current status of personalized medicine and combination inhaler therapy, and describes futuristic views for these two strategies.

Use of Asthma Medication During Gestation and Risk of Specific Congenital Anomalies

Poorly controlled asthma can affect neonatal outcomes including congenital anomalies, which can be reduced with appropriate asthma care during pregnancy. Although there is a concern regarding the safety of asthma medication use during pregnancy and congenital anomalies, the risk of uncontrolled asthma outweighs any potential risks of controller and reliever medication use. Patient education before and during pregnancy is critical to ensure good compliance to therapy and reduce the risk of poor asthma control.

Maternal Mortality in the United States: Trends and Opportunities for Prevention

Maternal mortality is unusually high in the United States compared to other wealthy nations and is characterized by major disparities in race/ethnicity, geography, and socioeconomic factors. Similar to other developed nations, the United States has seen a shift in the underlying causes of pregnancy-related death, with a relative increase in mortality resulting from diseases of the cardiovascular system and preexisting medical conditions. Improved continuity of care aimed at identifying reproductive-age women with preexisting conditions that may heighten the risk of maternal death, preconception management of risk factors for major adverse pregnancy outcomes, and primary care visits within the first year after delivery may offer opportunities to address gaps in medical care contributing to the unacceptable rates of maternal mortality in the United States.

Evaluation of first and second trimester maternal thyroid profile on the prediction of gestational diabetes mellitus and post load glycemia

Maternal thyroid alterations have been widely associated with the risk of gestational diabetes mellitus (GDM). This study aims to 1) test the first and the second trimester full maternal thyroid profile on the prediction of GDM, both alone and combined with non-thyroid data; and 2) make that prediction independent of the diagnostic criteria, by evaluating the effectiveness of the different maternal variables on the prediction of oral glucose tolerance test (OGTT) post load glycemia. Pregnant women were recruited in Concepción, Chile. GDM diagnosis was performed at 24-28 weeks of pregnancy by an OGTT (n = 54 for normal glucose tolerance, n = 12 for GDM). 75 maternal thyroid and non-thyroid parameters were recorded in the first and the second trimester of pregnancy. Various combinations of variables were assessed for GDM and post load glycemia prediction through different classification and regression machine learning techniques. The best predictive models were simplified by variable selection. Every model was subjected to leave-one-out cross-validation. Our results indicate that thyroid markers are useful for the prediction of GDM and post load glycemia, especially at the second trimester of pregnancy. Thus, they could be used as an alternative screening tool for GDM, independently of the diagnostic criteria used. The final classification models predict GDM with cross-validation areas under the receiver operating characteristic curve of 0.867 (p<0.001) and 0.920 (p<0.001) in the first and the second trimester of pregnancy, respectively. The final regression models predict post load glycemia with cross-validation Spearman r correlation coefficients of 0.259 (p = 0.036) and 0.457 (p<0.001) in the first and the second trimester of pregnancy, respectively. This investigation constitutes the first attempt to test the performance of the whole maternal thyroid profile on GDM and OGTT post load glycemia prediction. Future external validation studies are needed to confirm these findings in larger cohorts and different populations.

Asthma in pregnancy

Background: Asthma is a frequent and potentially life-threatening disease that complicates many pregnancies. There are extensive data with regard to the diagnosis and treatment of asthma during pregnancy. Medical providers require an up-to-date summary of the critical aspects of asthma management during pregnancy. Objective: This review aimed to summarize the available data from clinical trials, cohort studies, expert opinions, and guideline recommendations with regard to asthma in pregnancy. Methods: A search through PubMed was conducted by using keywords previously mentioned and MeSH (Medical Subject Headings) terminology. Clinical trials, observational studies, expert opinions, guidelines, and other reviews were included. The quality of the studies was assessed, and data were extracted and summarized. Results: Asthma worsens in ∼40% of pregnant women, which can be associated with maternal and fetal complications. Physiologic changes in the respiratory, cardiovascular, and immune systems during pregnancy play a critical role in the manifestations of asthma. The diagnosis and the treatment of asthma are similar to that of patients who are not pregnant. Nonetheless, concern for fetal malformations, preterm birth, and low birth weight must be considered when managing pregnant patients with asthma. Importantly, cornerstones of the pharmacotherapy of asthma seem to be safe during pregnancy. Conclusion: Asthma in pregnancy is associated with adverse outcomes. Roadblocks to management include associated comorbidities, medication nonadherence, atopy, lack of education, and smoking habits. These need to be acknowledged and addressed for successful asthma management during pregnancy.

Asthma in pregnancy - Management, maternal co-morbidities, and long-term health

Asthma is the most prevalent chronic disease in pregnancy, and as symptoms can change with pregnancy, and exacerbations of asthma are common, regular review of asthma symptoms, the provision of self-management education, and appropriate medication use are the hallmarks of management. Co-morbidities are also prevalent among pregnant women with asthma, with obesity, gestational diabetes, hypertension, rhinitis, depression, and anxiety, more common among women with asthma than women without asthma. Less is known about reflux, obstructive sleep apnoea and vocal cord dysfunction, along with nutritional deficiencies to iron and vitamin D. Maternal asthma impacts the offspring's long-term health, particularly in increasing the risk of early life wheeze and asthma in childhood. While breastfeeding may modify the risk of infant wheeze, less is known about the mechanisms involved. More research is needed to further understand the relationship between asthma in pregnancy and the risk of poor neurodevelopmental outcomes, such as autism.

Pulmonary disorders in pregnancy: Bronchiectasis, cystic fibrosis, sarcoidosis and interstitial diseases

This chapter aims to provide expert guidance to obstetricians, general practitioners, allied health staff and women with lung disease about the interactions between pregnancy and different lung diseases. This chapter will cover other airway diseases such as bronchiectasis and cystic fibrosis (CF) together with sarcoidosis and interstitial lung disease (ILD), noting that another chapter covers asthma. The physiological changes which occur in pregnancy, such as the changes in airway physiology, resting ventilation and sleep, are summarised in another chapter. This chapter extends the evidence-based approach and clinical expertise of the recent European Respiratory Society/Thoracic Society of Australia and New Zealand (ERS/TSANZ) taskforce. The papers selected were based on the population (pregnant women with lung disease other than asthma) and the effects of these diseases on risks of pregnancy-associated complications and miscarriages, breastfeeding, nutritional considerations, lung function, long-term maternal outcomes and management considerations during pregnancy. As there are very few randomised control trials in the area, the majority of the literature consists of observational studies (prospective or retrospective), cross-sectional surveys and case series. Other guidelines have also recently been published, which may be helpful to the reader.

Associations between antenatal maternal asthma status and placental DNA methylation

INTRODUCTION

Maternal asthma in pregnancy is associated with adverse perinatal and child health outcomes; however, mechanisms are poorly understood.

METHODS

The PRogramming of Intergenerational Stress Mechanisms (PRISM) prospective pregnancy cohort characterized asthma history during pregnancy via questionnaires and quantified placental DNAm using the Illumina Infinium HumanMethylation450 BeadChip. We performed epigenome-wide association analyses (n = 223) to estimate associations between maternal active or inactive asthma, as compared to never asthma, and placental differentially methylated positions (DMPs) and differentially variable positions (DVPs). Models adjusted for maternal pre-pregnancy body mass index, smoking status, parity, age and education level and child sex. P-values were FDR-adjusted.

RESULTS

One hundred and fifty-nine (71.3%) pregnant women reported no history of asthma (never asthma), 15 (6.7%) reported inactive, and 49 (22%) reported active antenatal asthma. Women predominantly self-identified as Black/Hispanic Black [88 (39.5%)] and Hispanic/non-Black [42 (18.8%)]. We identified 10 probes at FDR<0.05 and 4 probes at FDR<0.10 characterized by higher variability in maternal active asthma compared to never asthma mapping to GPX3, LHPP, PECAM1, ATAD3C, and ARHGEF4 and 2 probes characterized by lower variation mapping to CHMP4A and C5orf24. Amongst women with inactive asthma, we identified 52 probes, 41 at FDR<0.05 and an additional 11 at FDR <0.10, with higher variability compared to never asthma; BMP4, LHPP, PHYHIPL, and ZSCAN23 were associated with multiple DVPs. No associations were observed with DMPs.

DISCUSSION

We observed alterations in placental DNAm in women with antenatal asthma, as compared to women without a history of asthma. Further research is needed to understand the impact on fetal development.

Challenges in the successful management of asthma during conception, pregnancy and delivery

Asthma and infertility are the most common disorders among women of reproductive age. Time to pregnancy is prolonged in women with asthma, and importantly, age seems to be a more important risk factor regarding fertility in women with asthma compared to women without asthma. Some data have shown a higher frequency of miscarriages in women with asthma, although the data are conflicting on this issue as studies have observed no association between asthma and pregnancy loss. Furthermore, studies have shown no negative effect of asthma on the total number of offspring. Pregnancy may, thus, have a significant impact on women with asthma, as well as on their offspring.

The age of the women has an important impact on ability to conceive, but also for the pregnancy itself, with higher risk of uncontrolled asthma as well as asthma exacerbations with increasing age. Well-controlled asthma decreases the risk of maternal and fetal complications, while poorly controlled and undertreated asthma is associated with a range of risks for both mother and fetus. Asthma treatment should follow the general guidelines for asthma therapy, irrespective of pregnancy status, including treatment with inhaled corticosteroids, β2-agonists and muscarinic antagonists. Targeted treatment with biologics for severe asthma seems to be without important adverse effects. The use of systemic corticosteroids may be associated with adverse events during the first trimester; however, an exacerbation with the associated risk of hypoxaemia is worse for the fetus. Best possible asthma control may be achieved using repeated measurements of fractional exhaled nitric oxide (FENO), as the use of FENO compared with symptoms registration only has been shown to reduce exacerbation rate.

In conclusion, women with asthma should be encouraged to conceive at an early age, might experience miscarriages, but the number of offspring are the same as in women without asthma. Well treated asthma is important for the well-being of both the mother and the unborn fetus.

Epidemiology, Risk Factors, and Perinatal Outcomes of Placental Abruption-Detailed Annual Data and Clinical Perspectives from Polish Tertiary Center

Placental abruption (PA) is a separation of the placenta from the uterine wall occurring with the fetus still present in the uterine cavity. It contributes to numerous neonatal and maternal complications, increasing morbidity and mortality. We conducted a retrospective study at a tertiary perinatal care center, which included 2210 cases of labor that took place in 2015 with a PA occurrence of 0.7%. No maternal or fetal death during delivery was reported in this period. The identified PA risk factors were uterine malformations, pPROM, placenta previa spectrum, and oligohydramnios. The significant maternal PA complications identified were maternal anemia, uterine rupture, and HELLP syndrome. Preterm delivery occurred significantly more often in the PA group, and the number of weeks of pregnancy and the birth weight at delivery were both significantly lower in the PA group. PA is a relatively rare perinatal complication with very serious consequences, and it still lacks effective prophylaxis and treatment. Despite its rare occurrence, each center should develop a certain strategy for dealing with this pathology or predicting which patients are at risk. Much work is still needed to ensure the proper care of the mother and the baby in this life-threatening condition.

A cross-sectional survey of Australian healthcare professionals' confidence, evidence-based knowledge and guideline use for antenatal asthma management

BACKGROUND

Asthma is one of the most common chronic health conditions experienced during pregnancy and is associated with numerous adverse maternal and perinatal outcomes.

AIMS

To better understand the confidence, evidence-based knowledge and guideline use among healthcare professionals around Australia commonly involved in providing antenatal care for women with asthma.

MATERIALS AND METHODS

An online, cross-sectional survey was developed and distributed to maternity carers (obstetricians and midwives), primary carers (general practitioners and general practice nurses) and respiratory specialists (respiratory physicians and respiratory nurses). Self-reported confidence and use of clinical guidelines were recorded. Evidence-based knowledge was assessed with 13 questions relating to four clinical scenarios that covered recommendations from national and international guidelines.

RESULTS

Primary carers and respiratory specialists were more confident in providing antenatal asthma care, more likely to use clinical guidelines and scored significantly higher in evidence-based knowledge of antenatal asthma management than maternity carers (P < 0.01 and P < 0.001, respectively). There was no significant difference in evidence-based knowledge among healthcare professionals from metropolitan, regional and rural backgrounds. However, healthcare professionals who used clinical guidelines scored significantly higher than those who did not (P < 0.0001).

CONCLUSION

Greater utilisation of clinical guidelines could improve the evidence-based knowledge of maternity carers. However, the absence of antenatal asthma management in obstetric- and maternity-specific guidelines poses a potential barrier that needs to be addressed. Furthermore, the development of multidisciplinary antenatal clinics, staffed by respiratory nurses and/or physicians, could improve outcomes for pregnant women with asthma who are not undertaking shared care.

The environmental risk factors prior to conception associated with placental abruption: an umbrella review

BACKGROUND

The present umbrella review evaluated risk factors prior to conception associated with placental abruption based on meta-analyses and systematic reviews.

METHODS

We searched PubMed, Scopus, and Web of Science until June 25, 2021. All meta-analyses that had focused on assessing the risk factors associated with placental abruption were included. We calculated summary effect estimates, 95% CI, heterogeneity I2, 95% prediction interval, small-study effects, excess significance biases, and sensitive analysis. The quality of the meta-analyses was evaluated with A Measurement Tool to Assess Systematic Reviews 2 (AMSTAR 2).

RESULTS

There was no risk factor in the present umbrella review with the high level of evidence (class I or II). Eight risk factors including maternal asthma (RR 1.29 95% CI 1.14, 1.47), prior cesarean section (RR 1.38, 95% CI 1.35-1.42), cocaine using (RR 4.55, 95% CI 1.78-6.50), endometriosis (OR 1.40, 95% CI 1.12-1.76), chronic hypertension (OR 3.13, 95% CI 2.04-4.80), advanced maternal age (OR 1.44, 95% CI 1.35-1.54), maternal smoking (OR 1.80, 95% CI 1.75-1.85) (RR 1.65, 95% CI 1.51-1.80), and use of assisted reproductive techniques (ART) (OR 1.87, 95% CI 1.70-2.06) were graded as suggestive evidence (class III). The other four risk factors including pre-pregnancy underweight (OR 1.38, 95% CI 1.12-1.70), preeclampsia (OR 1.73, 95% CI 1.47-2.04), uterine leiomyoma (OR 2.63, 95% CI 1.38-3.88), and marijuana use (OR 1.78, 95% CI 1.32-2.40) were graded as risk factors with weak evidence (class IV).

CONCLUSION

Maternal asthma, prior cesarean section, cocaine use, endometriosis, chronic hypertension, advanced maternal age, maternal smoking, and use of ART, pre-pregnancy underweight, preeclampsia, uterine leiomyoma, and marijuana use were risk factors associated with placental abruption. Although factors associated with placental abruption have been investigated, the current meta-analytic associations cannot disentangle the complex etiology of placental abruption mainly due to their low quality of evidence.

Management of allergic diseases in pregnancy

Allergic diseases like asthma, allergic rhinitis, food allergy, hymenoptera allergy, or atopic dermatitis are highly prevalent in women of childbearing age and may affect up to 30% of this age group. This review focuses on the management of allergic diseases during pregnancy. Furthermore, we discuss the challenges of counseling women with allergic diseases in the reproductive age, including considerations relevant to the ongoing SARS-CoV-2 pandemic. To create the optimal milieu for the unborn child, a multitude of immunological changes occur during pregnancy which may favor type 2 responses and aggravate disease phenotypes. In co-occurrence with suboptimal preconception disease control, this elevated Th2 responses may aggravate allergic disease manifestations during pregnancy and pose a risk for mother and child. Due to limitations in conducting clinical trials in pregnant women, safety data on anti-allergic drugs during pregnancy are limited. The lack of information and concerns among pregnant patients demands counseling on the benefits of anti-allergic drugs and the potential and known risks. This includes information on the risk for mother and child of disease aggravation in the absence of treatment. By doing so, informed decisions and shared decision-making can take place.

Maternal respiratory health and intrauterine exposure-driven birthweight: a two-sample Mendelian randomization study

BACKGROUND

Observationally, poorer maternal respiratory health is associated with poorer birth outcomes, possibly confounded by socioeconomic position and other maternal attributes. We used multivariable Mendelian randomization (MR) to obtain unconfounded estimates of effect of maternal lung function on birthweight, independent of maternal height.

METHODS

Single nucleotide polymorphisms (SNPs) for forced expiratory volume in 1 second (FEV1) and forced vital capacity (FVC) in women were obtained from publicly available summary statistics from the UK Biobank. SNPs for asthma were obtained from the Trans-National Asthma Genetic consortium. SNPs for height in women were obtained from the Genetic Investigation of Anthropometric Traits consortium and the genetic estimates were obtained the UK Biobank. The genetic associations with maternally-driven birthweight were obtained from the Early Growth Genetics consortium. Multivariable MR estimates were obtained using inverse variance weighting with multivariable MR-Egger as sensitivity analysis.

RESULTS

Maternal lung capacity, as indicated by FVC, was positively associated with maternally-driven birthweight (0.08 per standard deviation, 95% confidence interval 0.01 to 0.15) independent of maternal height, whereas no clear such associations were shown for maternal airway function, indicated by FEV1 and peak expiratory flow, or for asthma, on maternally-driven birthweight. Similar findings were shown using MR-Egger.

CONCLUSIONS

These findings suggest that maternal lung function, especially lung capacity independent of maternal height, is directly associated with maternally-driven birthweight, and highlights the importance of maternal respiratory health in fetal growth.

Early Sensory and Temperament Features in Infants Born to Mothers With Asthma: A Cross-Sectional Study

Maternal asthma in pregnancy is associated with an increased risk of adverse perinatal outcomes. Adverse perinatal outcomes may result in poorer infant developmental outcomes, such as temperament and sensory difficulties. This study aimed to (1) assess differences in temperament and sensory features between infants born to mothers with and without asthma and (2) investigate differences in these infant behaviours as a function of maternal asthma severity and asthma control. Mothers completed the Carey Temperament Scales and the Sensory Profile 2 at either 6 weeks, 6 months, or 12 months postpartum. Overall, we observed no significant differences between infants born to mothers with and without asthma in their temperament or sensory features; scores in both domains fell within the normative range. More infants in the asthma group, however, were reported to be highly distractible. When compared with normative data, infants in both groups were reported to have poor predictability of biological functions and fewer infants engaged in low levels of sensory behaviours. Some infants were observed to experience difficulties with hyper-reactivity within several domains. Maternal asthma severity and control during pregnancy were not linked to significant differences between infant temperament and sensory features. The present findings indicate that infants born to mothers with asthma are not at an increased risk overall for temperament or sensory difficulties, compared to control infants. However, a subset of infants across both groups may be at risk for attention or sensory hyper-reactivity difficulties. Further research into the developmental outcomes of infants born to mothers with asthma is warranted.

Pregnancy Outcomes among Women with Intermittent Asthma: A Retrospective Cohort Study

BACKGROUND

It is already known that asthma strongly increases risks of poor pregnancy outcomes. We wonder whether intermittent asthma, the least severe form but accounting for the majority of cases, increases such adverse outcomes or not. Therefore, we conducted this study to compare adverse pregnancy outcomes between pregnancies with intermittent asthma and low-risk pregnancies (controls).

METHODS

The full medical records of pregnancies with intermittent asthma were comprehensively reviewed and low-risk pregnancies were randomly recruited as controls with a ratio of 10:1. The obstetric outcomes were compared between both groups, and the outcomes in the active subgroup of intermittent asthma (defined as at least one asthmatic attack during pregnancy) were also compared with the controls.

RESULTS

Of 364 study cases and 3640 controls, the rates of poor outcomes (preterm birth, preeclampsia, fetal growth restriction etc.) were not significantly different. However, cases with active disease slightly, but significantly, increased the risk of low birth weight. Moreover, mean gestational age was significantly lower in the study group.

CONCLUSIONS

A new insight gained from this study is that intermittent asthma is not associated with poor pregnancy outcomes, but cases with asthmatic attack during pregnancy tended to increase the risk of preterm birth and low birth weight. This information is important for counseling and the planning of antepartum management.

[Management of asthma during pregnancy]

Asthma is the most common chronic condition in pregnant women. The risks of complications associated with asthma for the mother, the foetus and the pregnancy are mainly due to uncontrolled asthma and the occurrence of exacerbations. These events are promoted by the patient's difficulty in complying with treatment or by prescription insufficiency for an unjustified fear of teratogenicity. The challenge of the management of asthma during pregnancy is to ensure optimal maternal asthma control in order to prevent foetal hypoxia and thus, reduce the risk of complications. Preventing the occurrence of asthma symptoms and exacerbations, ensuring optimal lung function and managing the risk factors of poor asthma outcomes and comorbidities are the principles necessary to achieve this goal. Because of the low or non-existent risks of the main treatments of asthma for the foetus and the mother, it is widely recommended that all therapies initiated before conception are continued, in particular inhaled corticosteroids, and to adjust the dosage to the minimum effective dose. During the preconception period and throughout pregnancy, coordination of the different healthcare professionals (general practitioner, respiratory specialist and gynecologist) is essential, with the mother-to-be playing a central role in the management of her asthma.

Asthma Across the Ages: Adults

Asthma is a common disease affecting approximately 300 million people worldwide, across all age ranges. Despite advances in asthma outcomes of the last few decades, there remains room for improvement in asthma management and for patient outcomes, particularly in older patients. The heterogeneity of asthma is now well recognized, and is known to complicate response to treatment and patient behavior and impact health outcomes. Asthma and its heterogeneity change according to age. Asthma affects people differently across the life span. In adults, prevalence is highest among those in middle age; however, mortality is greater in the older age group. In this clinical commentary, we describe how age impacts asthma prevalence and incidence, outcomes, disease expression, and approach to management in adulthood and in older patients.

Asthma and pregnancy in the 2020 decade: still a matter of concern

Asthma is a fairly common health problem for pregnant women and a potentially serious medical condition that may complicate pregnancy. Most complications are related to lack of disease control, which can adversely affect both maternal quality of life and perinatal outcomes. In this article, we review recent literature concerning asthma in pregnancy, describing the course of the disease and associated complications. Furthermore, we review and discuss asthma monitoring and management during pregnancy, labor and post-partum. The course of asthma symptoms during pregnancy is unpredictable but exacerbations are more common during the second trimester. The causes are multifactorial and asthma phenotype may have a role. It has been proposed that combined use of CARAT (Control of Allergic Rhinitis and Asthma Test) and lung function tests can be used to monitor and adjust therapy during pregnancy in patients with asthma. As a complement, an approach that considers airway inflammation assessment using fractional exhaled nitric oxide (FeNO), a noninvasive marker of inflammation, may improve asthma control during pregnancy. It is important to consider a few but relevant differences in asthma management and treatment regarding pregnancy and the peri-partum period to safely achieve optimal management of asthma during all these phases for both mother and offsprings.

The safety of asthma medications during pregnancy and lactation: Clinical management and research priorities

Asthma is one of the most common underlying diseases in women of reproductive age that can lead to potentially serious medical problems during pregnancy and lactation. A group of key stakeholders across multiple relevant disciplines was invited to take part in an effort to prioritize, strategize, and mobilize action steps to fill important gaps in knowledge regarding asthma medication safety in pregnancy and lactation. The stakeholders identified substantial gaps in the literature on the safety of asthma medications used during pregnancy and lactation and prioritized strategies to fill those gaps. Short-term action steps included linking data from existing complementary study designs (US and international claims data, single drug pregnancy registries, case-control studies, and coordinated systematic data systems). Long-term action steps included creating an asthma disease registry, incorporating the disease registry into electronic health record systems, and coordinating care across disciplines. The stakeholders also prioritized establishing new infrastructures/collaborations to perform research in pregnant and lactating women and to include patient perspectives throughout the process. To address the evidence gaps, and aid in populating product labels with data that inform clinical decision making, the consortium developed a plan to systematically obtain necessary data in the most efficient and timely manner.

Maternal asthma is associated with reduced lung function in male infants in a combined analysis of the BLT and BILD cohorts

RATIONALE

Asthma in pregnancy is associated with respiratory diseases in the offspring.

OBJECTIVE

To investigate if maternal asthma is associated with lung function in early life.

METHODS

Data on lung function measured at 5-6 weeks of age were combined from two large birth cohorts: the Bern Infant Lung Development (BILD) and the Australian Breathing for Life Trial (BLT) birth cohorts conducted at three study sites (Bern, Switzerland; Newcastle and Sydney, Australia). The main outcome variable was time to reach peak tidal expiratory flow as a percentage of total expiratory time(tPTEF:tE%). Bayesian linear hierarchical regression analyses controlling for study site as random effect were performed to estimate the effect of maternal asthma on the main outcome, adjusting for sex, birth order, breast feeding, weight gain and gestational age. In separate adjusted Bayesian models an interaction between maternal asthma and sex was investigated by including an interaction term.

MEASUREMENTS AND MAIN RESULTS

All 406 BLT infants were born to mothers with asthma in pregnancy, while 193 of the 213 (91%) BILD infants were born to mothers without asthma. A significant interaction between maternal asthma and male sex was negatively associated with tPTEF:tE% (intercept 37.5; estimate: -3.5; 95% credible interval -6.8 to -0.1). Comparing the model posterior probabilities provided decisive evidence in favour of an interaction between maternal asthma and male sex (Bayes factor 33.5).

CONCLUSIONS

Maternal asthma is associated with lower lung function in male babies, which may have lifelong implications on their lung function trajectories and future risk of wheezing and asthma.

Exacerbations of asthma following step-up and step-down inhaled corticosteroid and long acting beta agonist therapy in the managing asthma in pregnancy study

OBJECTIVE

Guidelines for asthma management contain a consensus recommendation that inhaled corticosteroid (ICS) dose should not be stepped down in pregnancy. However, this is not consistent with consumer preferences and pharmacological principles to minimize medication exposure during pregnancy. We investigated exacerbations after changes to ICS and long acting beta agonist (LABA) therapy in pregnant women with asthma.

METHODS

Pregnant women (n = 220) were recruited to a randomized controlled trial (RCT) where maintenance treatment was adjusted monthly based on either symptoms (control group), or fractional exhaled nitric oxide (FeNO, to alter ICS) and symptoms (to alter LABA, FeNO group). Exacerbations were monitored prospectively.

RESULTS

ICS were used by 137 (62.3%) women at some time during pregnancy. ICS dose remained unchanged in 16 women (11.7%, 95% confidence interval [CI] 7-18%), increased in 37 women (27%, 95%CI 20-35%), decreased in 34 women (24.8%, 95%CI 18%-33%), or both increased and decreased in 50 women (36.5%, 95%CI 29-45%). Exacerbations occurred within 14 days of ICS step-down in 11 women (13%, 95%CI 7.5%-22%). This was not significantly different from exacerbations occurring within 14 days of step-up, in 7 women (8.1%, 95%CI 4%-16%, P = 0.294). There were no differences between management groups. Exacerbations occurred within 14 days of step-down in 14.7% (95%CI 7%-30%) of women in the control group, and in 12% (95%CI 6%-24%) of women in the FENO group.

CONCLUSIONS

ICS step-down could be considered when eosinophilic inflammation or symptoms are low, and may be a useful management approach for women, doctors, and midwives wishing to minimize ICS exposure during pregnancy.

Pharmacotherapeutic management of asthma in pregnancy and the effect of sex hormones

INTRODUCTION

Asthma is a common medical condition that can frequently affect pregnancy, and thus optimal management of asthma in pregnancy is important for both mother and baby. This article reviews recent developments of asthma pharmacotherapy and provides emerging data on the safety of asthma controller medications and biological therapies in pregnancy. The authors highlight the clinical outcomes of asthma during pregnancy, and summarize emerging new data related to the influence of sex hormones and fetal sex on asthma severity.

AREAS COVERED

This review of asthma pharmacotherapy during pregnancy examines the recent guidelines and reports the most pertinent publications on safety data and asthma management.

EXPERT OPINION

Asthma management during pregnancy follows the same principles as that of non-pregnant asthma. The available data for most asthma medications are reassuring, however there is a lack of adequate safety data available because pregnant women are generally excluded from clinical trials. More clarity is needed in guidelines regarding the management of asthma in pregnancy, and high-quality randomized control trials are required to strengthen the evidence base and inform future guidelines. In particular, safety studies examining biological therapies in pregnant women with severe asthma are needed.

The impact of maternal asthma during pregnancy on fetal growth and development: a review

INTRODUCTION

Asthma is a highly prevalent co-morbidity during pregnancy that can worsen as gestation progresses and is associated with several adverse perinatal outcomes. These adverse outcomes often result from uncontrolled asthma during pregnancy and acute asthma exacerbations that are associated with alterations in placental function and fetal growth.

AREAS COVERED

This paper will discuss how maternal asthma in pregnancy affects fetal growth and development which may alter future offspring health. Changes in placental function occur in a sex-specific manner in pregnancies complicated by asthma and result in differences in fetal growth and development which may influence child health. The follow up of children from mothers with asthma suggests they are at greater risk of developing asthma, have alterations in microvascular structure that may contribute to a future risk of cardiovascular disease and epigenetic modifications in immune cell function. The current evidence suggests that appropriately managed asthma during pregnancy results in normal fetal growth and development.

EXPERT OPINION

Clinical management of asthma during pregnancy needs significant improvement to prevent adverse outcomes for the fetus. The key to improving maternal and fetal outcomes is through education of health professionals and parents about controlling asthma during pregnancy.

Maternal asthma and gestational diabetes mellitus: Exploration of potential associations

Asthma and gestational diabetes mellitus are prevalent during pregnancy and associated with adverse perinatal outcomes. The risk of gestational diabetes mellitus is increased with asthma, and more severe asthma; yet, the underlying mechanisms are unknown. This review examines existing literature to explore possible links.  Asthma and gestational diabetes mellitus are associated with obesity, excess gestational weight gain, altered adipokine levels and low vitamin D levels; yet, it's unclear if these underpin the gestational diabetes mellitus-asthma association. Active antenatal asthma management reportedly mitigates asthma-associated gestational diabetes mellitus risk. However, mechanistic studies are lacking.  Existing research suggests asthma management during pregnancy influences gestational diabetes mellitus risk; this may have important implications for future antenatal strategies to improve maternal-fetal outcomes by addressing both conditions. Addressing shared risk factors, as part of antenatal care, may also improve outcomes. Finally, mechanistic studies, to establish the underlying pathophysiology linking asthma and gestational diabetes mellitus, could uncover new treatment approaches to optimise maternal and child health outcomes.

[Woman's asthma throughout life: Towards a personalized management?]

In a woman's life, asthma can affect her in a variety of ways, with the onset of premenstrual asthma currently under-diagnosed. It is estimated that about 20% of women with asthma have premenstrual asthma, which is more common in patients with severe asthma. Women with asthma are at high risk of exacerbations and of severe asthma. Asthma is the most common chronic disease during pregnancy with potential maternal and foetal complications. Asthma medications are safe for the foetus and it is essential to continue pre-existing treatment and adapt it to the progress of asthma during the pregnancy. Sex steroids modulate the structure and function of bronchial and immune cells. Understanding their role in asthma pathogenesis is complicated by the ambivalent effects of bronchodilating and pro-inflammatory oestrogens as well as the diversity of response to their association with progesterone. Menopausal asthma is a clinical entity and is part of one of the phenotypes of severe non-allergic and low steroid-sensitive asthma. Targeted assessment of the domestic and professional environment allows optimization of asthma management.

ERS/TSANZ Task Force Statement on the management of reproduction and pregnancy in women with airways diseases

This European Respiratory Society/Thoracic Society of Australia and New Zealand statement outlines a review of the literature and expert opinion concerning the management of reproduction and pregnancy in women with airways diseases: asthma, cystic fibrosis (CF) and non-CF bronchiectasis. Many women with these diseases are now living into reproductive age, with some developing moderate-to-severe impairment of lung function in early adulthood. The statement covers aspects of fertility, management during pregnancy, effects of drugs, issues during delivery and the post-partum period, and patients' views about family planning, pregnancy and parenthood. The statement summarises current knowledge and proposes topics for future research, but does not make specific clinical recommendations.

Recent developments in asthma in pregnancy

PURPOSE OF REVIEW

Asthma affects up to 13% of pregnancies worldwide and has a varying and unpredictable clinical course during pregnancy. Pharmacological asthma treatment is recommended; however, studies show that some pregnant women with asthma cease their medication in early pregnancy. There is likely a large unmet disease burden arising from asthma in pregnancy.

RECENT FINDINGS

Antenatal and asthma guidelines lack sufficient information on asthma management in pregnant women, and implementation of the current guidelines seems inadequate. Prescription databases provide evidence of cessation of asthma medication during pregnancy on a population level. Population-based databases also provide evidence of rare adverse perinatal outcomes. The risk of childhood asthma in the offspring of women with asthma is reduced by adequate control of maternal asthma during pregnancy. Vitamin D sufficiency during pregnancy could also reduce the risk of childhood asthma.

SUMMARY

The findings of this review demonstrate the need for improved asthma and antenatal guidelines regarding asthma management during pregnancy, and the need of adequate implementation of these guidelines. Furthermore, adequate asthma control during pregnancy is needed to reduce the risk of childhood asthma. To maintain asthma control, prepregnancy medication should be continued throughout pregnancy and adjusted according to the current treatment steps if required.

Fractional exhaled nitric oxide-based asthma management: The feasibility of its implementation into antenatal care in New South Wales, Australia

BACKGROUND

The use of fractional exhaled nitric oxide (FeNO)-based asthma management during pregnancy can significantly reduce asthma exacerbations in non-smoking pregnant women. The feasibility of implementing this strategy into antenatal care has not been explored.

AIMS

To examine the feasibility of implementing FeNO-based asthma management into antenatal clinics in New South Wales (NSW) Australia.

MATERIALS AND METHODS

Semi-structured face-to-face interviews with video elicitation were conducted with healthcare professionals (HCPs) providing antenatal care in one of two hospital-based antenatal clinics in NSW, Australia. The video shown demonstrated the use of the FeNO instrument and other aspects of the management strategy, in antenatal care. Interviews were recorded, transcribed and analysed using qualitative content analysis.

RESULTS

A total of 20 interviews were conducted with 15 midwives, four obstetricians, and one general practitioner. Two main themes and ten sub-themes arose: Getting a number (sub-themes: engaging, technically easy, objective, predictive, reassuring); and Resourcing (sub-themes: time and timing, systems, staff, education and cost). Comments included: 'It's easy, fast and effective' and 'the main barrier is time'. All HCPs felt capable of facilitating the FeNO-based management strategy, with appropriate education, and were willing to undertake this strategy, saying: '…it would be perfectly acceptable for a midwife or doctor to do it'; also, 'they don't necessarily need to see a physician, it's something that midwives would take on generally…'.

CONCLUSION

Participants in this study considered FeNO-based asthma management for pregnant women to be a feasible addition to antenatal care following appropriate provision of resources and education.

Prodromal clinical, demographic, and socio-ecological correlates of asthma in adults: a 10-year statewide big data multi-domain analysis

Objectives: To identify prodromal correlates of asthma as compared to chronic obstructive pulmonary disease and allied-conditions (COPDAC) using a multi domain analysis of socio-ecological, clinical, and demographic domains.Methods: This is a retrospective case-risk-control study using data from Florida's statewide Healthcare Cost and Utilization Project (HCUP). Patients were grouped into three groups: asthma, COPDAC (without asthma), and neither asthma nor COPDAC. To identify socio-ecological, clinical, demographic, and clinical predictors of asthma and COPDAC, we used univariate analysis, feature ranking by bootstrapped information gain ratio, multivariable logistic regression with LogitBoost selection, decision trees, and random forests.Results: A total of 141,729 patients met inclusion criteria, of whom 56,052 were diagnosed with asthma, 85,677 with COPDAC, and 84,737 with neither asthma nor COPDAC. The multi-domain approach proved superior in distinguishing asthma versus COPDAC and non-asthma/non-COPDAC controls (area under the curve (AUROC) 84%). The best domain to distinguish asthma from COPDAC without controls was prior clinical diagnoses (AUROC 82%). Ranking variables from all the domains found the most important predictors for the asthma versus COPDAC and controls were primarily socio-ecological variables, while for asthma versus COPDAC without controls, demographic and clinical variables such as age, CCI, and prior clinical diagnoses, scored better.Conclusions: In this large statewide study using a machine learning approach, we found that a multi-domain approach with demographics, clinical, and socio-ecological variables best predicted an asthma diagnosis. Future work should focus on integrating machine learning-generated predictive models into clinical practice to improve early detection of those common respiratory diseases.

Maternal allergic asthma during pregnancy alters fetal lung and immune development in sheep: potential mechanisms for programming asthma and allergy

KEY POINTS

Experimental maternal allergic asthma in sheep provides an experimental model in which to test impacts on progeny. Fetuses from allergic asthmatic ewes had fewer surfactant-producing cells in lungs. A greater proportion of lymphocytes from thymus were CD44 positive in fetuses from allergic asthmatic ewes than in controls. These changes to fetal development might contribute to poor neonatal lung function and increased risk of allergy seen in offspring of pregnancies complicated by asthma.

ABSTRACT

Asthma is prevalent in pregnancy and increases the risk of disease in offspring, including neonatal respiratory distress and childhood asthma and allergy, but the mechanisms are not understood. We hypothesized that fetal lung structure and immune phenotype in late gestation fetal sheep would be impaired in our sheep model of maternal allergic asthma during pregnancy. Singleton-bearing ewes were either sensitized before pregnancy to house dust mite (HDM, allergic, n = 7) or were non-allergic (control, n = 5). The ewes were subsequently subjected to repeated airway challenges with HDM (allergic group) or saline (control group) throughout gestation. Tissues were collected at 140 ± 1 days gestational age (term, ∼147 days). The density of type II alveolar epithelial cells (surfactant protein C-immunostained) in the lungs was 30% lower in fetuses from allergic ewes than in controls (P < 0.001), but tissue-to-air space ratio and numbers of leucocytes and macrophages were not different between groups. The proportion of CD44⁺ lymphocytes in the fetal thymus was 3.5-fold higher in fetuses from allergic ewes than in control ewes (P = 0.043). Fewer surfactant-producing type II alveolar epithelial cells may contribute to the increased risk of neonatal respiratory distress in infants of asthmatic mothers, suggesting that interventions to promote lung maturation could improve their neonatal outcomes. If the elevated lymphocyte expression of CD44 persists postnatally, this would confer greater susceptibility to allergic diseases in progeny of asthmatic mothers, consistent with observations in humans. Further experiments are needed to evaluate postnatal phenotypes of progeny and investigate potential interventions.

Antenatal asthma management by midwives in Australia - Self-reported knowledge, confidence and guideline use

BACKGROUND

Asthma affects approximately 12.7% of pregnant women in Australia. Increased maternal and infant morbidity is closely associated with poorly controlled asthma during pregnancy. Midwives are well placed to provide antenatal asthma management but data on current asthma management during pregnancy is not available, nor is the use of guidelines for clinical practice by this health professional group.

AIM

To explore self-reported antenatal asthma management provided by midwives across Australia and how this reflects guideline recommendations.

METHOD

An online survey was developed and distributed throughout Australia via the Australian College of Midwives, social media and healthcare facilities.

RESULTS

Responses from 371 midwives were obtained. Ten percent of midwives rated their knowledge as 'good' and 1% as 'very good', with 39% 'poor' or 'very poor'. Being 'somewhat' or 'not at all' confident to provide antenatal asthma management was noted by 87% of midwives. Clinical guidelines were referred to by 50% of midwives and 40% stated that their main role was to refer women to other healthcare professionals. Only 54% reported that a clear referral pathway existed. Most respondents (>90%) recognised key recommendations for asthma management such as smoking cessation, appropriate vaccinations, and the continuation of prescribed asthma medications.

CONCLUSION

Although midwives appear aware of key clinical recommendations for optimal antenatal asthma management, low referral to clinical practice guidelines and lack of knowledge and confidence was evident. Further research is required to determine what care pregnant women with asthma are actually receiving and identify strategies to improve antenatal asthma management by midwives.