Association of Asthma Diagnosis, Severity, Symptoms, and Treatment With Risk of Preeclampsia

Chronic Management of Asthma During Pregnancy

Asthma is one of the most common potentially serious medical problems to complicate pregnancy. Optimal management of asthma during pregnancy is thus important for both mother and baby. Treating asthmatic women requires understanding the effects of pregnancy on the course of asthma, and, conversely, the effects of asthma on pregnancy outcomes. Successful management also requires an understanding the barriers to asthma control in this population of patients. Evidence has shown that it is essential that the allergist-immunologist, obstetrician, and patient work as a team during pregnancy to achieve optimal maternal and neonatal outcomes.

The obstetric aspects of maternal asthma

Asthma is the commonest chronic medical condition encountered in pregnancy. Poor asthma control and exacerbations are frequently encountered due to treatment non-adherence, pregnancy-related aggravating factors such as increased susceptibility to viral infections, and comorbidities that are commonly associated. Asthma-related inflammatory reactions and placental effects, the effect of medications, and respiratory symptoms and hypoxia are probably to interact to result in an increased adverse obstetric outcomes including miscarriage, foetal congenital anomalies, pregnancy hypertensive disorders, gestational diabetes, preterm labour and birth, antepartum haemorrhage, low birthweight and foetal growth restriction (FGR), caesarean delivery, postpartum haemorrhage (PPH), maternal intensive care admission, and even mortality, while the offspring also has increased long-term morbidity. Interdisciplinary management with frequent assessment by symptoms, spirometry, and biomarkers, together with removal of risk factors such as smoking and appropriate instigation of treatment including short courses of systemic corticosteroid, could ensure optimal and tailored treatment to control symptoms, prevent exacerbations, and ultimately enhancing maternal and perinatal outcomes.

Contemporary management and treatment strategies for asthma during pregnancy

Introduction: Asthma is one of the most common conditions that afflict pregnant women. Because uncontrolled asthma in pregnancy affects both maternal and offspring outcomes, careful attention to maintaining control of asthma symptoms throughout pregnancy is of critical importance.Areas Covered: Using a search of PUBMED/MEDLINE for 'asthma and pregnancy,' this article will review the current literature regarding epidemiology and course of asthma in pregnancy, the effects of uncontrolled asthma on both the mother and offspring, and provide an overview of the management, both non-pharmacologic and pharmacologic, of asthma in pregnancy.Expert Opinion: There is a lack of adequate safety information for most medications taken during pregnancy. Future research might allow better methods to predict which women will experience worsening during pregnancy. For now, surveillance systems like pregnancy registries or observational cohort studies can provide safety information for medications used during pregnancy.

Residential mobility of pregnant women and implications for assessment of spatially-varying environmental exposures

Health studies on spatially-varying exposures (e.g., air pollution) during pregnancy often estimate exposure using residence at birth, disregarding residential mobility. We investigated moving patterns in pregnant women (n = 10,116) in linked cohorts focused on Connecticut and Massachusetts, U.S., 1988-2008. Moving patterns were assessed by race/ethnicity, age, marital status, education, working status, population density, parity, income, and season of birth. In this population, 11.6% of women moved during pregnancy. Movers were more likely to be younger, unmarried, and living in urban areas with no previous children. Among movers, multiple moves were more likely for racial/ethnic minority, younger, less educated, unmarried, and lower income women. Most moves occurred later in pregnancy, with 87.4% of first moves in the second or third trimester, although not all cohort subjects enrolled in the first few weeks of pregnancy. Distance between first and second residence had a median value of 5.2 km (interquartile range 11.3 km, average 57.8 km, range 0.0-4277 km). Women moving larger distances were more likely to be white, older, married, and work during pregnancy. Findings indicate that residential mobility may impact studies of spatially-varying exposure during pregnancy and health and that subpopulations vary in probability of moving, and timing and distance of moves.

Investigating the Impact of Maternal Residential Mobility on Identifying Critical Windows of Susceptibility to Ambient Air Pollution During Pregnancy

Identifying periods of increased vulnerability to air pollution during pregnancy with respect to the development of adverse birth outcomes can improve understanding of possible mechanisms of disease development and provide guidelines for protection of the child. Exposure to air pollution during pregnancy is typically based on the mother's residence at delivery, potentially resulting in exposure misclassification and biasing the estimation of critical windows of pregnancy. In this study, we determined the impact of maternal residential mobility during pregnancy on defining weekly exposure to particulate matter less than or equal to 10 μm in aerodynamic diameter (PM10) and estimating windows of susceptibility to term low birth weight. We utilized data sets from 4 Connecticut birth cohorts (1988-2008) that included information on all residential addresses between conception and delivery for each woman. We designed a simulation study to investigate the impact of increasing levels of mobility on identification of critical windows. Increased PM10 exposure during pregnancy weeks 16-18 was associated with an increased probability of term low birth weight. Ignoring residential mobility when defining weekly exposure had only a minor impact on the identification of critical windows for PM10 and term low birth weight in the data application and simulation study. Identification of critical pregnancy windows was robust to exposure misclassification caused by ignoring residential mobility in these Connecticut birth cohorts.

Pregnancy-associated diamine oxidase originates from extravillous trophoblasts and is decreased in early-onset preeclampsia

Human extravillous trophoblast (EVT) invasion of the pregnant uterus constitutes a pivotal event for the establishment of the maternal-fetal interface. Compromised EVT function manifesting in inadequate arterial remodeling is associated with the severe pregnancy disorder early-onset preeclampsia (eoPE). Recent studies suggest that EVTs invade the entire uterine vasculature including arteries, veins and lymphatics in the first trimester of pregnancy. We therefore hypothesized that EVT-derived factors accumulate in the circulation of pregnant women early in gestation and may serve to predict eoPE. In contrast to published literature, we demonstrate that placenta-associated diamine oxidase (DAO) is not expressed by maternal decidual cells but solely by EVTs, especially when in close proximity to decidual vessels. Cultures of primary EVTs express and secret large amounts of bioactive DAO. ELISA measurements indicate a pregnancy-specific rise in maternal DAO plasma levels around gestational week (GW) 7 coinciding with vascular invasion of EVTs. Strikingly, DAO levels from eoPE cases were significantly lower (40%) compared to controls in the first trimester of pregnancy but revealed no difference at mid gestation. Furthermore, DAO-containing pregnancy plasma rapidly inactivates pathophysiologically relevant histamine levels. This study represents the first proof of concept suggesting EVT-specific signatures as diagnostic targets for the prediction of eoPE.

The Association of Maternal Asthma and Early Pregnancy Vitamin D with Risk of Preeclampsia: An Observation From Vitamin D Antenatal Asthma Reduction Trial (VDAART)

BACKGROUND

Maternal asthma, uncontrolled asthma, and low vitamin D levels during pregnancy have been individually linked to increased risk of preeclampsia.

OBJECTIVE

To investigate the association of history of physician-diagnosed asthma and uncontrolled asthma status during pregnancy with the risk of preeclampsia and the effects of early pregnancy vitamin D concentrations on this relationship.

METHODS

A total of 816 subjects with available pregnancy outcome data and risk factors of interest were analyzed. A group of experienced obstetricians and gynecologists from 3 study centers validated the preeclampsia diagnoses. Vitamin D was measured using the DiaSorin method at 10 to 18 weeks of gestation. The Pregnancy-Asthma Control Test was used to assess asthma control during pregnancy. Criterion-based stepwise variable selection algorithm was applied to investigate the relationships of risk factors of interest (history of asthma diagnosis, uncontrolled asthma during pregnancy, and vitamin D) to preeclampsia.

RESULTS

The incidence of preeclampsia was not related to the presence of asthma diagnosis (8.9% with vs 7.4% without). The adjusted odds of preeclampsia controlled for maternal serum 25-hydroxyvitamin D (25OHD) concentrations was higher for women with a higher proportion of uncontrolled asthma months per visit during pregnancy (adjusted odds ratio, 3.55; 95% CI, 1.15-13.0). Adjusting for asthma control status during pregnancy, an additional decrease in the associated preeclampsia risk by 7% was observed for a 10-unit (ng/mL) increase in early pregnancy 25OHD levels (adjusted odds ratio10-unit, 0.60; 95% CI, 0.43-0.82) as compared with the previous risk estimate of preeclampsia associated with low maternal 25OHD unadjusted for asthma control status.

CONCLUSIONS

Uncontrolled asthma during pregnancy is associated with an increased risk of preeclampsia. Early pregnancy 25OHD contributes to the association of uncontrolled asthma status with preeclampsia.

Folic acid supplement use and the risk of gestational hypertension and preeclampsia

BACKGROUND

Hypertensive disorders of pregnancy are among the leading causes of maternal morbidity and mortality. Studies suggest that the use of folic acid may lower the risk of hypertensive disorders in pregnant women.

AIM

The aim of this study was to assess the effects of timing and duration of folic acid-containing supplement use on the risk for gestational hypertension and preeclampsia.

METHODS

Exposures and outcomes data were obtained through interviews and review of participant's medical records from the MotherToBaby cohort studies across the United States and Canada. Demographics, medical history, lifestyle factors, substance use, and fetal sex were assessed as potential confounders. Unadjusted and adjusted risks for gestational hypertension and preeclampsia were examined using odds ratios and 95% confidence intervals.

FINDINGS

3247 women were included in the study. Compared to non-supplement use, early and late supplement use were not significantly associated with the development of gestational hypertension or preeclampsia. The odds of developing gestational hypertension and preeclampsia were significantly reduced as the duration of folic acid-containing supplement use increased.

CONCLUSION

Findings from this study suggest that the use of folic acid-containing supplements may mitigate the risk for gestational hypertension and preeclampsia.

Allergic diseases and asthma in pregnancy, a secondary publication

Every fifth pregnant woman is affected by allergies, especially rhinitis and asthma. Allergic symptoms existing before pregnancy may be either attenuated, or equally often promoted through pregnancy. Optimal allergy and asthma diagnosis and management during pregnancy is vital to ensure the welfare of mother and baby. For allergy diagnosis in pregnancy, preferentially anamnestic investigation as well as in vitro testing should be applied, whereas skin testing or provocation tests should be postponed until after birth. Pregnant women with confirmed allergy should avoid exposure to, or consumption of the offending allergen. Allergen immunotherapy should not be initiated during pregnancy. In patients on immunotherapy since before pregnancy, maintenance treatment may be continued, but the allergen dose should not be increased further. Applicable medications for asthma, rhinitis or skin symptoms in pregnancy are discussed and listed. In conclusion, i) allergies in pregnancy should preferentially be diagnosed in vitro; ii) AIT may be continued, but not started, and symptomatic medications must be carefully selected; iii) management of asthma and allergic diseases is important during pregnancy for welfare of mother and child.

Pharmacological difficulties in the treatment of asthma in pregnant women

INTRODUCTION

This is a review of the diagnosis and management of asthma in the pregnant patient. Asthma may adversely affect both maternal quality of life and, perinatal outcomes. Optimal management of asthma is thus important for both mother and baby. Areas covered: Special attention is paid to the challenges in diagnosis and management of asthma during pregnancy. Expert commentary: This article reviews the safety of asthma medications commonly used during pregnancy.

Particulate air pollution, fetal growth and gestational length: The influence of residential mobility in pregnancy

BACKGROUND

It remains unclear as to whether neglecting residential mobility during pregnancy introduces bias in studies investigating air pollution and adverse perinatal outcomes, as most studies assess exposure based on residence at birth. The aim of this study was to ascertain whether such bias can be observed in a study on the effects of PM10 on risk of preterm birth and fetal growth restriction.

METHODS

This was a retrospective study using four pregnancy cohorts of women recruited in Connecticut, USA (N=10,025). We ascertained associations with PM10 exposure calculated using first recorded maternal address, last recorded address, and full address histories. We used a discrete time-to-event model for preterm birth, and logistic regression to investigate associations with small for gestational age (SGA) and term low birth weight (LBW).

RESULTS

Pregnant women tended to move to areas with lower levels of PM10. For all outcomes, there was negligible difference between effect sizes corresponding to exposures calculated with first, last and full address histories. For LBW, associations were observed for exposure in second trimester (OR 1.09; 95% CI: 1.04-1.14 per 1μg/m(3) PM10) and whole pregnancy (OR 1.08; 95% CI: 1.02-1.14). For SGA, associations were observed for elevated exposure in second trimester (OR 1.02; 95% CI: 1.00-1.04) and whole pregnancy (OR 1.03; 95% CI: 1.01-1.05). There was insufficient evidence for association with preterm birth.

CONCLUSION

PM10 was associated with both SGA and term LBW. However, there was negligible benefit in accounting for residential mobility in pregnancy in this study.

Pharmacotherapy options to treat asthma during pregnancy

INTRODUCTION

Pregnancy may be complicated by new onset or pre-existing asthma. This article reviews the recognition and management of asthma during pregnancy, paying close attention to the general principles of asthma medication use during pregnancy. Asthma is one of the most common potentially serious medical problems to complicate pregnancy, and asthma may adversely affect both maternal quality of life and perinatal outcomes. Therefore, optimal management of asthma during pregnancy is important for both mother and baby. This article reviews asthma pharmacotherapy during pregnancy, with an emphasis on gestational safety of commonly used medications.

AREAS COVERED

In this review of asthma pharmacotherapy during pregnancy, the most pertinent recent publications are reported. Electronic databases such as PubMed were searched for terms pregnan* or perinat* or obstet* and asthma or wheeze and treatment.

EXPERT OPINION

Although retrospective data have been reassuring, since pregnant women are generally excluded from clinical trials, there is a lack of adequate safety information for most medications taken during pregnancy. One of the most important needs for the future is the availability of further safety information for asthma medications used during pregnancy that can also account for asthma control.

Exacerbations of asthma during pregnancy: Impact on pregnancy complications and outcome

Asthma is common among pregnant women, and the incidence of asthma exacerbations during pregnancy is high. This literature review provides an overview of the impact of exacerbations of asthma during pregnancy on pregnancy-related complications. The majority of published retrospective studies reveal that asthma exacerbations during pregnancy increase the risk of pre-eclampsia, gestational diabetes, placental abruption and placenta praevia. Furthermore, these women also have higher risk for breech presentation, haemorrhage, pulmonary embolism, caesarean delivery, maternal admission to the intensive care unit and longer postpartum hospital stay. Asthma has been associated with increased risk of intrauterine growth retardation, small-for-gestational age, low birth weight, infant hypoglycaemia and preterm birth, but more recent prospective studies have not revealed significant associations with regard to these outcomes. In conclusion, asthma exacerbations during pregnancy are associated with complications of pregnancy, labour and delivery. Prevention of exacerbations is essential to reduce the risk of complications and poor outcome.

Effect of pregnancy in asthma on health care use and perinatal outcomes

BACKGROUND

It is generally known that pregnancy in asthmatic patients increases the risk of asthma exacerbations and poor perinatal outcomes. However, the effect of pregnancy in asthmatic patients on health care use is not known well. In addition, its effect on perinatal outcomes is still controversial because of study limitations caused by ethical issues. National Health Insurance claim data are an ideal resource for studying real-world health care use patterns of asthma.

OBJECTIVE

We sought to evaluate the effect of pregnancy on asthma in terms of asthma-related health care use and prescription patterns in concert with the effect of asthma exacerbations on adverse pregnancy outcomes.

METHODS

Among all asthmatic patients in the Korean National Health Insurance claim database from January 2009 to December 2013, pregnant women who delivered in 2011 with pre-existing asthma were enrolled. Analyses included asthma-related health care use and prescription patterns compared between pregnant asthmatic women and nonpregnant female asthmatic control subjects, as well as within the pregnant subjects from before pregnancy throughout postpartum periods. In addition, the association between asthma exacerbation during pregnancy and adverse pregnancy outcomes was assessed.

RESULTS

A total of 3,357 pregnant asthmatic patients were compared with 50,355 nonpregnant asthmatic patients, and 10,311 pregnant patients were included to determine the effect of asthma exacerbations on adverse pregnancy outcome in the study. Pregnant asthmatic patients underwent more asthma-related hospitalizations (1.3% vs 0.8%, P = .005) but had significantly fewer outpatient visits and prescriptions for most asthma medications than nonpregnant asthmatic patients. The proportion of patients ever hospitalized gradually increased throughout pregnancy (first trimester, 0.2%; second trimester, 0.5%; and third trimester, 0.7%; P = .018). The prevalence of asthma exacerbation during pregnancy was 5.3%, and the patients who had acute exacerbation during pregnancy had significantly higher asthma-related health care use in terms of hospitalization, intensive care unit admission, and emergency department and outpatient visits within 1 year before delivery than those who had not. However, asthma exacerbation during pregnancy was not significantly related to adverse perinatal outcomes, except for cesarean section (27.1% vs 18.9%, P < .001). All exacerbations were managed with systemic corticosteroids, and the patients who ever experienced acute exacerbations maintained asthma medications, including inhaled corticosteroid-based inhalers, throughout the pregnancy period.

CONCLUSION

Pregnancy profoundly affects asthma-related health care use but to a different degree depending on whether the patient experienced an exacerbation. Asthma exacerbation during pregnancy is not associated with adverse pregnancy outcomes while managed appropriately with systemic corticosteroids. However, further studies are needed to clarify the effect of asthma control on perinatal outcome and delivery method.

Safety of therapeutic options for treating asthma in pregnancy

INTRODUCTION

Pregnancy may be complicated by new onset or preexisting asthma. Asthma is one of the most common potentially serious medical problems to complicate pregnancy, and it may adversely affect both maternal quality of life and perinatal outcomes. Optimal management of asthma during pregnancy is thus important for both mother and baby.

AREAS COVERED

This article reviews the recognition and management of asthma during pregnancy, paying close attention to the general principles of asthma medication use during pregnancy. Further, the article reviews the safety of asthma medications commonly used during pregnancy. In this article, the most pertinent recent publications are reported. Electronic databases, such as PUBMED, were searched for terms pregnan* or perinat* or obstet* and asthma or wheeze and treatment.

EXPERT OPINION

Because pregnant women are generally excluded from clinical trials, there is a lack of adequate safety information for most medications taken during pregnancy. One of the most important requirements for the future is the availability of further safety information for asthma medications used during pregnancy that can also account for asthma control.

The safety of asthma medications during pregnancy: an update for clinicians

Pregnancy may be complicated by new onset or preexisting asthma. This article reviews the recognition and management of asthma during pregnancy, as well as general principles of asthma medication use during pregnancy.

Birth after preeclamptic pregnancies: association with allergic sensitization and allergic rhinoconjunctivitis in late childhood; a historically matched cohort study

Background

The development of allergic sensitization and allergic disease may be related to factors during intrauterine life, but the role of maternal preeclampsia is not known.

We studied if maternal preeclampsia is associated with long-term allergic sensitization, allergic rhinoconjunctivitis, atopic dermatitis, asthma and with altered lung function in late childhood.

Methods

617 children participated in a 1:2 matched and controlled historical cohort study; 230 born after preeclamptic pregnancies and 387 born after normotensive pregnancies. Specific IgE in serum and lung function were measured at the age of 12.8 years and questionnaires on maternal and adolescent data were completed at the ages of 10.8 years (girls) and 11.8 years (boys), and at 12.8 years (both genders). The association between birth after preeclampsia and the main outcome measures allergic sensitization, allergic rhinoconjunctivitis, atopic dermatitis, asthma and lung function in late childhood were analysed with multiple regression analyses, including possible confounders.

Results

Severe maternal preeclampsia was associated with high level allergic sensitization (sum of specific IgE in serum ≥ 3.9 kU/l; the 25 percentile for all children being sensitized); odds ratio (OR): 3.79; 95% confidence interval (CI): (1.54, 9.32); p = 0.015 and with allergic rhinoconjunctivitis in offspring; OR: 2.22, 95% CI: (1.19, 4.14), p = 0.047. Preeclampsia was not associated with atopic dermatitis, asthma or altered lung function in late childhood.

Conclusion

Maternal preeclampsia was associated with allergic sensitization and allergic rhinoconjunctivitis in offspring in late childhood, but not with other atopic diseases.

Management of asthma during pregnancy

The prevalence of asthma in pregnant women appears to be increasing. Recent evidence demonstrates that pregnant asthmatic women with moderate-to-severe asthma may have an increased risk of adverse perinatal outcomes. The goal of asthma management during pregnancy is to optimize maternal and fetal health.

A meta-analysis of adverse perinatal outcomes in women with asthma

BACKGROUND

Asthma is a common condition during pregnancy and may be associated with adverse perinatal outcomes.

OBJECTIVE

This meta-analysis sought to establish if maternal asthma is associated with an increased risk of adverse perinatal outcomes, and to determine the size of these effects.

SEARCH STRATEGY

Electronic databases were searched for the following terms: (asthma or wheeze) and (pregnan* or perinat* or obstet*).

SELECTION CRITERIA

Cohort studies published between 1975 and March 2009 were considered for inclusion. Studies were included if they reported at least one perinatal outcome in pregnant women with and without asthma.

DATA COLLECTION AND ANALYSIS

A total of 103 articles were identified, and of these 40 publications involving 1,637,180 subjects were included. Meta-analysis was conducted with subgroup analyses by study design and active asthma management.

MAIN RESULTS

Maternal asthma was associated with an increased risk of low birthweight (RR 1.46, 95% CI 1.22-1.75), small for gestational age (RR 1.22, 95% CI 1.14-1.31), preterm delivery (RR 1.41, 95% CI 1.22-1.61) and pre-eclampsia (RR 1.54, 95% CI 1.32-1.81). The relative risk of preterm delivery and preterm labour were reduced to non-significant levels by active asthma management (RR 1.07, 95% CI 0.91-1.26 for preterm delivery; RR 0.96, 95% CI 0.73-1.26 for preterm labour).

AUTHOR'S CONCLUSIONS

Pregnant women with asthma are at increased risk of perinatal complications, including pre-eclampsia and outcomes that affect the baby's size and timing of birth. Active asthma management with a view to reducing the exacerbation rate may be clinically useful in reducing the risk of perinatal complications, particularly preterm delivery.

Association of the variants in AGT gene with modified drug response in Korean aspirin-intolerant asthma patients

The angiotensinogen (AGT) gene enhances the effect of several bronchoconstrictors and produces a peptide that is accumulated in the airways of asthma patients; events that may underpin the pathogenesis of aspirin-intolerant asthma (AIA). To carry out a case-control analysis between AGT and aspirin-induced bronchospasm following treatment with an anti-asthma drug, montelukast (MLK), 38 single nucleotide polymorphisms (SNPs) in AGT were genotyped in 56 AIA cohort. Genotyping was performed with TaqMan assay and haplotypes were inferred using PHASE algorithm ver. 2.0. Statistical analyses of each SNPs and haplotypes were performed using SAS version 9.1. Among 13 variants displaying significant signals, two SNPs (+2401C>G and +2476C>T) in the intronic region of AGT were significantly associated with modification of drug response even after correction for multiple testing (P=0.0009-0.002; P(corr)=0.02-0.03). Furthermore, the two variants also exhibited associations with MLK response rate (P=0.0003-0.0006; P(corr)=0.006-0.01). Although our results are preliminary and further replication in a larger-scale group of subjects should be warranted, these observations provide evidence that AGT variants might be one of genetic factors involved in the response of anti-asthma drugs in AIA patients.

Association of seasonality with hypertension in pregnancy: a systematic review

A systematic literature review was conducted to examine all academic, peer-reviewed studies of seasonal or monthly variation in the prevalence of gestational hypertension, preeclampsia, or eclampsia. The objective was to test the hypothesis that prevalence rates are highest during the winter months in non-tropical regions and during wet or humid periods in tropical climates. The authors searched the epidemiological literature indexed in PubMed, cross-referenced bibliographic materials, and reviewed personal archives. Of 60 abstracts and articles screened, 20 met the final inclusion criteria. Studies included were published between 1938 and 2010. Despite differences in setting, data sources, study design, outcome definitions, and control of known risk factors, 16 separate studies (11 non-tropical and 5 tropical) concurred that prevalence rates were higher for winter delivery in non-tropical regions or delivery during wet or humid periods in tropical climates. Although the reasons for these patterns are unknown, seasonal variation in infectious diseases, environmental triggers of asthma, vitamin D levels, physiological responses to cold temperatures, healthcare access, and nutritional intake may all play a role.

Asthma in pregnancy

Worldwide the prevalence of asthma among pregnant women is on the rise, and pregnancy leads to a worsening of asthma for many women. This article examines the changes in asthma that may occur during pregnancy, with particular reference to asthma exacerbations. Asthma affects not only the mother but the baby as well, with potential complications including low birth weight, preterm delivery, perinatal mortality, and preeclampsia. Barriers to effective asthma management and opportunities for optimized care and treatment are discussed, and a summary of the clinical guidelines for the management of asthma during pregnancy is presented.

Asthma in pregnancy

Asthma is an increasingly common problem during pregnancy. Mild and moderate asthma can be associated with excellent maternal and perinatal pregnancy outcomes, especially if patients are managed according to contemporary recommendations of National Asthma Education and Prevention Program. Severe and poorly controlled asthma may be associated with increased prematurity, need for cesarean delivery, preeclampsia, and growth restriction. Severe asthma exacerbations can result in maternal morbidity and mortality, and can have commensurate adverse pregnancy outcomes. The management of asthma during pregnancy should be based upon objective assessment, trigger avoidance, patient education, and step therapy. Asthma medications should be continued during pregnancy and while breast-feeding.

Asthma and pregnancy: a review of two decades

The prevalence of asthma among pregnant women varies among studies from 4 to 8%, making it by far the most common respiratory disorder complicating pregnancy. Controversy exists among the numerous retrospective and prospective studies regarding pregnancy outcomes of asthmatic patients. Overall, the literature indicates that women with severe asthma are at an increased risk for preterm delivery, low birth weight, preeclampsia and Caesarean delivery, especially in the absence of inhaled corticosteroid therapy. Asthmatic women carrying a female fetus may particularly be at increased risk of these adverse outcomes. On the other hand, mild or moderate, well-controlled asthma is associated with favorable pregnancy and perinatal outcomes. Pregnancy also influences the course of asthma. Recently published data indicate that the real risk for an exacerbation during pregnancy may be underestimated. There is no question, however, that the risk of having an exacerbation correlates closely with the severity of asthma. The mechanisms responsible for these changes are not fully understood. Maternal hypoxia or inflammatory processes have been suggested and could explain reduced fetal growth through alterations in placental function. The goal of asthma therapy is to maintain adequate oxygenation of the fetus by prevention of exacerbations. Optimal management of asthma during pregnancy should include scheduled monitoring of objective lung function tests, avoiding triggers, patient education and tailored pharmacologic therapy. Inhaled corticosteroids are the treatment of choice for all levels of persistent asthma, yet other drug classes, such as beta(2)-agonists and theophylline, are effective and safe for use during pregnancy.

Successful pregnancy outcome in Swyer-James-Macleod syndrome

Swyer-James-MacLeod (SJM) syndrome is a chronic, progressive lung disease as a result of infection and bronchial obstruction that ultimately leads to emphysema. It is associated with chronic cough, sputum production and recurrent chest infections and is occasionally seen in women of reproductive age. The radiological finding of unilateral hyperlucent lung is considered synonymous with the disease entity.

The relationship of asthma-specific quality of life during pregnancy to subsequent asthma and perinatal morbidity

OBJECTIVE

To determine whether asthma-specific quality of life during pregnancy is related to asthma exacerbations and to perinatal outcomes.

METHODS

This was a secondary analysis of data from a randomized controlled trial of inhaled beclomethasone versus theophylline in the treatment of moderate asthma during pregnancy. The Juniper Asthma Quality of Life Questionnaire (AQLQ) was administered to patients at enrollment. Exacerbations were defined as asthma symptoms requiring a hospitalization, unscheduled medical visit, or oral corticosteroid course.

RESULTS

Quality of life assessments were provided by 310 of the 385 participants who completed the study. There was more than a 25% decrease in the odds of a subsequent asthma exacerbation for every 1-point increase in AQLQ score for the overall score (odds ratio [OR] 0.73, 95% confidence interval [CI] 0.55-0.96), emotion domain (OR 0.72, 95% CI 0.59-0.88), and symptoms domain (OR 0.73, 95% CI 0.57-0.94). These relationships were not significantly influenced by initial symptom frequency or forced expiratory volume in 1 s (FEV(1)). No significant relationships were demonstrated between enrollment AQLQ scores and preeclampsia, preterm birth, low birth weight, or small for gestational age.

CONCLUSION

Asthma-specific quality of life in early pregnancy is related to subsequent asthma morbidity during pregnancy but not to perinatal outcomes.

[Asthma and pregnancy. Review of the current literature and management according to the GINA 2006-2007 guidelines]

INTRODUCTION

Many pregnant women are asthmatics and maternal asthma is a source of questions and complications concerning both the progress of the pregnancy itself and the impact on the foetus. In this situation good asthma control is essential as the disease can deteriorate with acute exacerbations, possibly precipitated by reduction or even withdrawal of treatment on account of fear of teratogenicity.

BACKGROUND

Even though asthma treatments are not totally harmless during pregnancy, their use has been validated by several studies and guidelines. To help clinicians, we undertake here a review of the complications induced by maternal asthma and its medications, and then suggest management guidelines according to the most recent publications.

CONCLUSIONS

The risks and benefits of asthma treatments should be explained in a real partnership between the patient and her general practitioner and specialists (obstetrician, chest physician or allergist). In order to reduce complications to both mother and child, perfect control of asthma is required and inhaled steroids remain the treatment of choice for partially or uncontrolled asthma in the pregnant woman.

Adverse maternal outcomes in women with asthma versus women without asthma

The purpose of this retrospective cohort study was to examine differences in adverse maternal outcomes between pregnant women with asthma and pregnant women without asthma. A total of 7,777 pregnant patients with asthma were abstracted from a national database. The comparison group was 31,108 women, randomly selected from 541,719 pregnant women without asthma. Logistic regression was used to examine the relationship of asthma to 12 maternal outcome measures. Odds ratios were used to approximate the association of how much more likely pregnant women with asthma were to have adverse maternal outcomes. Pregnant women with asthma were more likely to have adverse maternal outcomes than did the pregnant women without asthma.

Preeclampsia--a pressing problem: an executive summary of a National Institute of Child Health and Human Development workshop

On September 21 and 22, 2006, the National Institute of Child Health and Human Development of the National Institutes of Health sponsored a 2-day workshop titled "Preeclampsia--A Pressing Problem." The purpose of the workshop was to bring together leaders in the field to present and discuss their diverse research areas, which ranged from basic science to clinical trials and management, and to identify scientific gaps. This article is a summary of the proceedings of that workshop. Although much progress is being made in understanding the underpinnings of preeclampsia, a number of research gaps are identified that, if filled, would hasten progress in the field. It is the overall consensus that preeclampsia is a multifactorial disease whose pathogenesis is not solely vascular, genetic, immunologic, or environmental but a complex combination of factors. In addition, a number of specific scientific gaps are identified including insufficient multidisciplinary and collaborative research, clinical trials and studies of patient management, and a lack of in-depth mechanistic research. The research community needs to focus on these gaps to better understand the disease, with the ultimate goal of preventing the disorder.

The link between the epidemics of obesity and allergic diseases: does obesity induce decreased immune tolerance?

There is increasing epidemiological evidence that obesity increases the risk of asthma, atopic, and autoimmune diseases. We hypothesize that the increase in these diseases is caused, at least in part, by decreased immunological tolerance as a consequence of immunological changes induced by adipokines (e.g. leptin and adiponectin) and cytokines [e.g. interleukin 6 (IL6) and tumor necrosis factor alpha (TNFalpha)] secreted by white adipose tissue. The increasing body weight increases the levels of circulating IL6, leptin, and TNFalpha. IL6 and leptin down-regulate the activity of regulatory T-lymphocytes (Tregs). Additionally, adiponectin, which decreases with increasing obesity, down-regulates the secretion of IL10 from macrophages and adipocytes. These changes in IL6, leptin, and IL10 decrease the regulatory effect of Tregs resulting in decreased immunological tolerance to antigens. In pregnant women, these obesity-induced immunological changes might be transmitted to the fetus by epigenetic inheritance thereby increasing the risk of atopic disease. We propose that obesity results in immunological changes resulting in decreased immunological tolerance to antigens and skewing of the immune system towards a Th2 cytokine profile increasing the risk of allergy and other immune-mediated diseases. Furthermore, this hypothesis offers a unifying explanation for the observation that older siblings appear to confer protection against atopic diseases, preeclampsia, and certain autoimmune diseases. More studies are definitely needed to explore further the immunological effects of obesity and its possible effects on allergic disease.

Effect of maternal asthma and asthma control on pregnancy and perinatal outcomes

BACKGROUND

Asthma is a common condition during pregnancy.

OBJECTIVE

We sought to determine the effect of asthma on the rates of adverse pregnancy and fetal outcomes.

METHODS

We identified pregnancies among black and white women age 15 to 44 with singleton gestations enrolled in the Tennessee Medicaid program over a period of 9 consecutive years, from 1995to 2003, and used claims data to determine the relationship of maternal asthma and asthma exacerbations on pregnancy and infant outcomes.

RESULTS

Among the 140,299 pregnancies, 6.5% were in women with asthma. Among women with asthma, 23% had a hospital or emergency department visit (exacerbated asthma); 40% of black and 23% of white women received hospital or emergency department care for asthma during pregnancy. After controlling for race and other covariates, birth weights among infants of women with asthma were, on average, 38 g lower, and among infants of women with exacerbated asthma they were, on average, 56 g lower. There were moderate, dose-dependent relationships between asthma alone and exacerbated asthma with hypertensive disorders of pregnancy, membrane-related disorders, preterm labor, antepartum hemorrhage, and cesarean delivery. Maternal asthma was not associated with preterm birth or birth defects.

CONCLUSION

Asthma is a risk factor for several common adverse outcomes of pregnancy, and poorly controlled asthma during pregnancy increases these risks.

CLINICAL IMPLICATIONS

It is possible that both maternal and infant outcomes could be improved in this population with appropriate asthma care, especially among black women.

Racial/ethnic differences in the monthly variation of preeclampsia incidence

OBJECTIVE

The purpose of this study was to assess monthly patterns in preeclampsia risk separately by race/ethnicity.

STUDY DESIGN

We conducted a cohort study of 20,794 white women and 18,916 black women who received care at 12 hospitals in the United States.

RESULTS

Among white women, there was a significant U-shaped trend in the incidence of preeclampsia: the incidence was highest in winter months, reached its nadir in mid August, and subsequently increased through the fall months (P < .05). When compared with occurrences in January, the adjusted odds ratios were 0.65 (0.43, 0.99) for May, 0.76 (95% CI, 0.51, 1.13) for June, 0.64 (95% CI, 0.43, 0.97) for July, and 0.64 (95% CI, 0.42, 0.96) for August. Among black women, there was no association between month of delivery and preeclampsia risk (P = .81).

CONCLUSION

Our finding that the incidence of preeclampsia decreases in white women during the summer months and that no pattern exists in black women suggests that, in each subgroup, different or competing environmental exposures may be important for the pathogenesis of preeclampsia.

A comprehensive analysis of adverse obstetric and pediatric complications in women with asthma

RATIONALE

Previous studies have raised concern that women with asthma have increased risks of adverse obstetric and pediatric complications, but these have generally been underpowered.

OBJECTIVES

To quantify risks of major adverse pregnancy outcomes and obstetric complications in women with and without asthma.

METHODS

We extracted information on 281,019 pregnancies from the Health Improvement Network database between 1988 and 2004. We analyzed the data using logistic regression.

MEASUREMENTS AND MAIN RESULTS

In 37,585 pregnancies of women with asthma compared with 243,434 pregnancies of women without asthma, risks of stillbirth and therapeutic abortion were similar; however, the risk of miscarriage was slightly higher (odds ratio [OR], 1.10; 95% confidence interval [CI], 1.06-1.13). Risks of most obstetric complications (placental abruption, placental insufficiency, placenta previa, preeclampsia, hypertension, gestational diabetes, thyroid disorders in pregnancy, and assisted delivery) were not higher in pregnancies of women with asthma compared with those without asthma, with the exception of increases in antepartum (OR, 1.20; 95% CI, 1.08-1.34) or postpartum (OR, 1.38; 95% CI, 1.21-1.57) hemorrhage, anemia (OR, 1.06; 95% CI, 1.01-1.12), depression (OR, 1.52; 95% CI, 1.36-1.69), and caesarean section (OR, 1.11; 95% CI, 1.07-1.16). Risks of miscarriage, depression, and caesarean section increased moderately in women with more severe asthma and previous asthma exacerbations.

CONCLUSIONS

We found some increased risks in women with asthma that need to be considered in the future; however, our results indicate that women with asthma have similar reproductive risks compared with women without asthma in the general population for most of the range of outcomes studied.

Asthma and pregnancy

Asthma complicates 4-8% of pregnancies. Mild and well-controlled moderate asthma can be associated with excellent maternal and perinatal pregnancy outcomes. Severe and poorly controlled asthma may be associated with increased prematurity, need for cesarean delivery, preeclampsia, growth restriction, other perinatal complications, as well as maternal morbidity and mortality. Optimal management of asthma during pregnancy includes objective monitoring of lung function, avoiding or controlling asthma triggers, patient education, and individualized pharmacologic therapy. Those with persistent asthma should be monitored by peak expiratory flow rate, spirometry to measure the forced expiratory volume in 1 second, or both. Step-care therapeutic approach uses the least amount of drug intervention necessary to control a patient's severity of asthma. Inhaled corticosteroids are the preferred treatment for the management of all levels of persistent asthma during pregnancy. It is safer for pregnant women with asthma to be treated with asthma medications than it is for them to have asthma symptoms and exacerbations. The ultimate goal of asthma therapy is maintaining adequate oxygenation of the fetus by prevention of hypoxic episodes in the mother. Asthma exacerbations should be aggressively managed, with a goal of alleviating asthma symptoms and attaining peak expiratory flow rate or forced expiratory volume in 1 second of 70% predicted or more. Pregnancies complicated by moderate or severe asthma may benefit from ultrasound for fetal growth and accurate dating and antenatal assessment of fetal well-being. Asthma medications should be continued during labor, and parturients should be encouraged to breastfeed.

Women with asthma: a review of potential variables and preferred medical management

OBJECTIVES

To summarize the potential variables that contribute to the increased risk of asthma in women, outline therapeutic strategies that address these variables, and review current treatment recommendations for both pregnant and nonpregnant women with asthma.

DATA SOURCES

Literature searches (MEDLINE and cross-references) were performed using the keywords asthma and women in combination with the terms compliance, depression, emergency department, hormones, menstruation, mortality, National Asthma Education and Prevention Program, osteoporosis, pregnancy, prevalence, smoking, and treatment. Searches were limited to human studies with data published before 2005.

STUDY SELECTION

The author selected relevant articles for inclusion in this review.

RESULTS

Fluctuations in sex hormones, menstruation, pregnancy, obesity, depression, medication nonadherence, and smoking may contribute to increased asthma symptoms or severity in women. Asthma control may be improved if physicians address conditions and behaviors associated with asthma variability and severity in women. Notably, asthma must be managed aggressively in pregnant women, because uncontrolled asthma can lead to perinatal complications. Asthma treatment in women is optimized through patient and physician adherence to national guideline recommendations, including provision of patient education and asthma action plans.

CONCLUSIONS

Multiple variables throughout the female life cycle may influence asthma control. Successful asthma management requires an ongoing partnership between the patient and her physician to address physiologic (eg, sex hormones, pregnancy, obesity, depression) and nonphysiologic (eg, smoking, medication nonadherence) factors that may contribute to decreased asthma control.

The epidemiology of asthma during pregnancy: prevalence, diagnosis, and symptoms

We demonstrated that asthma remains a common condition among pregnant women and that the prevalence of self-reported asthma in the United States is between 8.4% and 8.8%. In addition, approximately 4.1% of all pregnant women experienced an asthma attack in the previous year. Prevalence rates in other countries seem to be higher or substantially lower; however, further characterization of international trends using nationally representative data is needed. Data from a large prospective cohort study in the northeastern United States and national data demonstrate continued opportunities for population-level improvement in well-managed asthma during pregnancy. Finally, asthma diagnosis and asthma control seem to differ by population characteristics (eg, age, race/ethnicity, socio-economic status), and further research and clinical involvement are needed to ad-dress potentially systematic variation in reporting and management of the disease.

Outcomes of pregnancy in asthmatic women

Mild and moderate asthma can be associated with excellent maternal and perinatal pregnancy outcomes, especially if patients are managed according to contemporary NAEPP recommendations. Severe and poorly controlled asthma may be associated with increased mild prematurity (<37 weeks' gestation), a need for cesarean delivery, preeclampsia, and growth restriction. Poorly controlled asthma and severe asthma exacerbations can result in maternal morbidity and mortality, which can have commensurate adverse pregnancy outcomes.

Current guidelines for the management of asthma during pregnancy

Over the past few years, much has been learned that is relevant to the management of asthma in pregnancy. Although the studies that were reviewed here in provide more insight into the mechanisms that are involved and the treatment of asthma during pregnancy, there are more questions to be answered. It is hoped that the updated guidelines, which address the safety of contemporary asthma medications during pregnancy, will be a helpful resource in the treatment of our pregnant asthmatic patients.

Pregnancy outcome of asthmatic patients: a population-based study

OBJECTIVE

To investigate pregnancy outcome of asthmatic patients.

METHODS

A retrospective population-based study comparing all singleton pregnancies in women with and without asthma was conducted. Patients lacking prenatal care (less than three visits in prenatal care facilities) were excluded from the study. Deliveries occurred during the years 1988-2002. Stratified analysis, using a multiple logistic regression model was performed to control for confounders.

RESULTS

During the study period 139 168 singleton deliveries occurred, of which 1.4% in asthmatic patients (n = 963). Using a multivariate analysis, with backward elimination, the following complications were significantly associated with maternal asthma: diabetes mellitus (OR = 1.8, 95%CI 1.5-2.0, p < 0.001), fertility treatments (OR = 1.6, 95%CI 1.3-2.1, p < 0.001), intrauterine growth restriction (IUGR) (OR = 1.5, 95%CI 1.1-1.9, p = 0.004), hypertensive disorders (OR = 1.5, 95%CI 1.2-1.7, p < 0.001) and premature rupture of membranes (OR = 1.2, 95%CI 1.1-1.5, p = 0.013). Higher rates of cesarean deliveries were found among asthmatic patients as compared to the controls (17.1% vs. 11.4%, p < 0.001). This association persisted even after controlling for possible confounders such as failure to progress in labor, mal-presentations, IUGR, etc. No significant differences regarding low Apgar scores (less than 7) at 1 and 5 minutes were noted between the groups (3.9% vs. 4.4%, p = 0.268 and 0.4% vs. 0.6%, p = 0.187, respectively). Likewise, the perinatal mortality rate was similar among patients with and without asthma (1.3% vs. 1.3%, p = 0.798).

CONCLUSION

Pregnant women with asthma are at an increased risk for adverse maternal outcome. This association persists after controlling for variables considered to co-exist with maternal asthma. However, perinatal outcome is favorable. Careful surveillance is required in pregnancies of asthmatic patients, for early detection of possible complications.

Preeclampsia, gestational hypertension and intrauterine growth restriction, related or independent conditions?

OBJECTIVE

Preeclampsia, gestational hypertension, and unexplained intrauterine growth restriction may have similar determinants and consequences. In this study, we compared determinants and perinatal outcomes associated with these obstetric conditions.

STUDY DESIGN

We analyzed 39,615 pregnancies (data from the WHO Antenatal Care Trial), of which 2.2% were complicated by preeclampsia, 7.0% by gestational hypertension, and 8.1% by unexplained intrauterine growth restriction (ie, not associated with maternal smoking, maternal undernutrition, preeclampsia, gestational hypertension, or congenital malformations). We compared the risk factors associated with these groups. Fetal death, preterm delivery, and severe neonatal morbidity and mortality were the primary outcomes. Logistic regression analyses were adjusted for study site, socioeconomic status, and (if appropriate) birth weight and gestational age.

RESULTS

Diabetes, renal or cardiac disease, previous preeclampsia, urinary tract infection, high maternal age, twin pregnancy, and obesity increased the risk of both hypertensive conditions. Previous large-for-age birth, reproductive tract surgery, antepartum hemorrhage and reproductive tract infection increased the risk for gestational hypertension only. Independent of maternal age, primiparity was a risk factor only for preeclampsia. Both preeclampsia and gestational hypertension were associated with increased risk for fetal death and severe neonatal morbidity and mortality. Mothers with preeclampsia compared with those with unexplained intrauterine growth restriction were more likely to have a history of diabetes, renal or cardiac disease, chronic hypertension, previous preeclampsia, body mass index more than 30 kg/cm2, urinary tract infection and extremes of maternal age. Conversely, unexplained intrauterine growth restriction was associated with higher risk of low birth weight in previous pregnancies, but not with previous preeclampsia. Both conditions increased the risk for perinatal outcomes independently but preeclampsia was associated with considerable higher risk.

CONCLUSION

Preeclampsia and gestational hypertension shared many risk factors, although there are differences that need further evaluation. Both conditions significantly increased morbidity and mortality. Conversely, preeclampsia and unexplained intrauterine growth restriction, often assumed to be related to placental insufficiency, seem to be independent biologic entities.

Metabolism of synthetic steroids by the human placenta

Pregnant women with asthma are frequently exposed to synthetic glucocorticoids and glucocorticoids are known to reduce fetal growth. The fetus is normally protected from the harmful effects of maternally derived glucocorticoids by the placental enzyme 11beta-hydroxysteroid dehydrogenase type 2 (11beta-HSD2). Whether 11beta-HSD2 inactivates the synthetic glucocorticoids used for asthma treatment during pregnancy (budesonide, beclomethasone dipropionate and fluticasone propionate) remains unknown. To investigate the relationship between steroid use during pregnancy and fetal growth and development, pregnant women with (n=119) and without asthma (n=84) were followed throughout pregnancy. Data on asthma medication use, neonatal size at birth, placental weight and cord blood cortisol and estriol were collected. Placental tissue samples were collected from non-asthmatic women (n=8) for metabolism studies. Placental 11beta-HSD2 activity was determined using beclomethasone dipropionate, budesonide, fluticasone propionate, prednisolone, dexamethasone and betamethasone as steroid substrates. Steroids and their oxidised metabolites were examined using thin layer chromatography and densitometry. Placental 11beta-HSD2 metabolised beclomethasone, prednisolone, dexamethasone and betamethasone, but not budesonide or fluticasone. No association between the use of inhaled steroids for asthma treatment during pregnancy and alterations in neonatal size, placental weight, gestational age at delivery, or umbilical vein estriol concentrations was demonstrated compared to non-asthmatic women. In conclusion, the use of inhaled steroids for asthma treatment does not affect fetal growth, despite differences in placental metabolism by 11beta-HSD2.

The effect of maternal asthma on placental and cord blood protein profiles

OBJECTIVE

We conducted a comparative proteomic analysis of placental and umbilical cord blood proteins using surface-enhanced laser desorption ionization-time of flight mass spectrometry (SELDI-TOF MS) to examine the associations among asthma, fetal gender, and protein profiles.

METHODS

Placental tissue and umbilical vein plasma were collected from 10 healthy and 20 asthmatic women. Placental proteins were extracted using phosphate-buffered saline containing protease inhibitors. Samples were applied to the surfaces of strong anion exchange (SAX2), weak cation exchange (WCX2) and immobilized metal affinity capture (IMAC-Cu(2+)) chips. Mass analysis was conducted using a Ciphergen Protein Biology System IIc (Freemont, CA), and differences in individual peak intensities between groups were determined.

RESULTS

Fourteen placental peaks were significantly different between asthmatic and non-asthmatic women (seven more highly expressed and seven less highly expressed). Ten umbilical cord blood peak differences were identified, with four peaks more highly expressed and six peaks less highly expressed in asthmatics. Four placental and three umbilical cord blood proteins differed significantly between male and female fetuses. Two placental and five umbilical cord blood peaks were specifically increased in a subgroup of samples collected from asthmatic women who did not use inhaled glucocorticoids and were pregnant with a female fetus, a group previously found to have altered placental function.

CONCLUSIONS

This study demonstrates the abilities of the SELDI technique as a tool for protein profiling in tissue or plasma. Further work to positively identify the candidate peptides found in this study may provide a greater understanding of the placental mechanisms leading to alterations in fetal growth in patients with bronchial asthma.

Increased interferon-gamma- and interleukin-4-synthesizing subsets of circulating T lymphocytes in pregnant asthmatics

BACKGROUND

Pregnancy frequently interferes with the course of bronchial asthma, and asthmatic pregnant women experience less successful pregnancies. T lymphocytes synthesizing IL-4 or IFN-gamma are important in allergic mechanisms of the airways as well as in materno-fetal immunity.

OBJECTIVE

We hypothesized that pregnancy (a T helper-2 polarized state) of asthmatics will enhance the number of circulating T2 lymphocytes, but decrease the subset-producing IFN-gamma (T1 lymphocytes) and thereby cause a culminating T2 dominance with possible clinical consequences.

METHODS

IL-4- or IFN-gamma-producing T lymphocytes were determined by flow cytometry in healthy (n=8) and asthmatic (n=13) non-pregnant women and healthy (n=18) and asthmatic (n=48) pregnant women of similar chronological and gestational (2nd-3rd trimester) age and asthma severity (Global Initiative for Asthma II-III).

RESULTS

In the blood of non-pregnant women--healthy or asthmatic--the numbers of IL-4- and IFN-gamma+ T cells were very low (<10/microL blood). In contrast, in asthmatic pregnant women, the cell counts were 182+/-27 and 39+/-6 for IFN-gamma+ and IL-4+ T cells/microL blood, respectively (both P<0.05 vs. respective control values of non-pregnant asthmatics). Within the asthmatic pregnant group, significant negative correlations were revealed between the numbers of IFN-gamma+ or IL-4+ T cells and maternal peak expiratory flow as well as birth weight of newborns (both P<0.05).

CONCLUSION

These data show a previously unknown immunological interference between asthma and pregnancy. The culminating proliferation of IFN-gamma+ and IL-4+ T lymphocytes may potentially impair maternal airway symptoms as well as fetal development.

Severe Asthma Exacerbations During Pregnancy

OBJECTIVE

To estimate the frequency of severe asthma exacerbations in pregnant women and to estimate whether there is an association with adverse perinatal outcomes.

METHODS

Asthma exacerbations were evaluated in 146 women who were enrolled in a prospective cohort study of asthma and pregnancy. A severe exacerbation was defined as a hospital admission, emergency department presentation, or unscheduled doctor visit for asthma or a course of oral corticosteroids. Women were classified as having mild (n = 63), moderate (n = 34), or severe (n = 49) asthma.

RESULTS

Severe exacerbations occurred in 8% (95% confidence interval [CI] 1.3-14.6%) of women with mild asthma, 47% (95% CI 30.3-63.8%) of women with moderate asthma, and 65% (95% CI 52-78.6%) of women with severe asthma at a mean gestational age of 25.1 +/- 0.9 (range 9-39) weeks of gestation. Among women who had severe exacerbations, there were 2 male stillbirths (P = .102) and a significantly increased rate of male low birth weight (P = .03). Maternal age, lung function, body mass index, gravidity, and parity were not different between women who did or those who did not have a severe exacerbation. Maternal pregnancy weight gain was significantly lower in women who had a severe exacerbation (P = .039). Forty-three percent of severe exacerbations occurred in winter, 34% were associated with self-reported viral infection, and 29% with nonadherence to inhaled corticosteroid medication.

CONCLUSION

The exacerbation rate among pregnant women with asthma is high and associated with poor outcomes for the male fetus. Improvements in asthma management to prevent severe exacerbations may lead to a better outcome for both mother and baby.

LEVEL OF EVIDENCE

II-2.

Treatment of asthma during pregnancy and perinatal outcomes

PURPOSE OF REVIEW

Asthma is the most common, potentially serious medical problem to complicate pregnancy. Women with asthma have been shown to be at increased risk of complications during pregnancy. Managing asthma during pregnancy is unique because the effect of both the illness and the treatment on the developing fetus as well as the patient must be considered. This review summarizes the recent studies addressing the effects of asthma or asthma medications on perinatal outcomes, including the 2004 Asthma and Pregnancy Working Group of the National Asthma Education and Prevention Program.

RECENT FINDINGS

This review summarizes the recent studies addressing the effect of asthma or asthma medications on perinatal outcomes.

SUMMARY

The prevalence of asthma in pregnant women appears to be increasing. Recent evidence supports that pregnant women with moderate to severe asthma may have an increased risk of adverse perinatal outcomes. The goal of asthma management during pregnancy is to optimize maternal and fetal health.