Pre-eclampsia, placental abruption and increased risk of atopic sensitization in male adolescent offspring

Childhood growth outcomes 2 years after hypertensive versus normotensive pregnancy: a P4 study

BACKGROUND

Intrauterine exposure to hypertensive disorders of pregnancy, including gestational hypertension (GH) and preeclampsia (PE), may influence infant growth and have long-term health implications. This study aimed to compare growth outcomes of infants exposed to a normotensive pregnancy (NTP), GH, or PE from birth to 2 years.

METHODS

Infants were children of women enroled in the prospective Postpartum Physiology, Psychology and Paediatric (P4) cohort study who had NTP, GH or PE. Birth, 6-month (age-corrected) and 2-year (age-corrected) weight z-scores, change in weight z-scores, rapid weight gain (≥0.67 increase in weight z-score) and conditional weight gain z-scores were calculated to assess infant growth (NTP = 240, GH = 19, PE = 66).

RESULTS

Infants exposed to PE compared to NTP or GH had significantly lower birth weight and length z-scores, but there were no differences in growth outcomes at 6 months or 2 years. GH and PE-exposed infants had significantly greater weight z-score gain [95% CI] (PE = 0.93 [0.66-1.18], GH = 1.03 [0.37-1.68], NTP = 0.45 [0.31-0.58], p < 0.01) and rapid weight gain (GH = 63%, PE = 59%, NTP = 42%, p = 0.02) from birth to 2 years, which remained significant for PE-exposed infants after confounder adjustment.

CONCLUSION

In this cohort, GH and PE were associated with accelerated infant weight gain that may increase future cardiometabolic disease risk.

IMPACT

Preeclampsia exposed infants were smaller at birth, compared with normotensive pregnancy and gestational hypertension exposed infants, but caught up in growth by 2 years of age. Both preeclampsia and gestational hypertension exposed infants had significantly accelerated weight gain from birth to 2 years, which remained significant for preeclampsia exposed infants after adjustment for confounders including small for gestational age. Monitoring of growth patterns in infants born following exposure to a hypertensive disorder of pregnancy may be indicated to prevent accelerated weight gain trajectories and obesity.

A review of infant growth and psychomotor developmental outcomes after intrauterine exposure to preeclampsia

Preeclampsia is a hypertensive disorder of pregnancy with serious health implications for mother and their offspring. The uteroplacental vascular insufficiency caused by preeclampsia is associated with epigenetic and pathological changes in the mother and fetus. However, the impact of preeclampsia in infancy (birth to 2 years), a time of rapid development influenced by pre- and postnatal factors that can predict future health outcomes, remains inconclusive. This narrative review of 23 epidemiological and basic science studies assessed the measurement and impact of preeclampsia exposure on infant growth and psychomotor developmental outcomes from birth to 2 years. Studies assessing infant growth report that preeclampsia-exposed infants have lower weight, length and BMI at 2 years than their normotensive controls, or that they instead experience accelerated weight gain to catch up in growth by 2 years, which may have long-term implications for their cardiometabolic health. In contrast, clear discrepancies remain as to whether preeclampsia exposure impairs infant motor and cognitive development, or instead has no impact. It is additionally unknown whether any impacts of preeclampsia are independent of confounders including shared genetic factors that predispose to both preeclampsia and childhood morbidity, perinatal factors including small for gestational age or preterm birth and their sequelae, and postnatal environmental factors such childhood nutrition. Further research is required to account for these variables in larger cohorts born at term, to help elucidate the independent pathophysiological impact of this clinically heterogenous and dangerous disease.

Clinical outcomes of hypertensive disorders in pregnancy in the offspring during perinatal period, childhood, and adolescence

Hypertensive disorders during pregnancy (HDP) could have significant clinical impact not only on the mother's, but also on the offspring's health. The clinical impact of HDP may be evident early in the perinatal period or during childhood and adolescence. The cardiovascular system seems to be primarily affected with higher rates of congenital heart defects reported from cohort studies in the offspring of mothers with HDP. HDP are associated with alterations in cardiac and vascular structure and higher BP during childhood. HDP may also affect brain development and could result in increased prevalence of adverse cognitive outcomes and neuropsychiatric disorders in children and adolescents. The kidney, immune, endocrine, and gastrointestinal system abnormalities could also have their origin in exposure to HDP. The aim of this narrative review is to examine the clinical impact of HDP on the offspring with a focus on the perinatal period, childhood, and adolescence.

Hypertensive disorders during pregnancy and health outcomes in the offspring: a systematic review

The hypertensive disorders of pregnancy complicate up to 10% of pregnancies worldwide and are a leading cause of maternal, foetal, and neonatal morbidity and mortality. The aim of this study was to present an overview of recent studies addressing offspring's medium and long-term health outcomes after intrauterine exposure to maternal hypertension. A search on PubMed/MEDLINE and Bireme databases was conducted to identify observational studies that reported any offspring outcome measured after the 6th month of life. The search was limited to studies published after May 2008. Forty-five articles were included and categorized into four groups of outcomes: cardiovascular, immune, metabolic and behavioural/neurological effects. According to our findings, hypertensive disorders of pregnancy had an overall negative impact on offspring's cardiovascular, immune and neurological health, although not all parameters analysed in each group had consistent results among studies. The most prominent and reliable associations were verified between gestational hypertension and higher offspring's blood pressure and between preeclampsia and offspring's lower cognitive functioning. In the metabolic outcomes, body composition had conflicting results among papers, while all studies that examined blood biomarkers showed no evidence that preeclampsia or gestational hypertension could be associated with an alteration of this metabolic outcomes. Most included studies were highly heterogeneous regarding the measure of outcomes and covariables used for adjustments. Future studies should consider using the same protocols and cut-off points already published so that results can be better compared and summarized. This review was registered in PROSPERO.

REGISTRATION NUMBER

CRD42015020838.

Hypertensive disorders of pregnancy, respiratory outcomes and atopy in childhood

Few epidemiological studies have investigated the role of hypertensive disorders of pregnancy in the aetiology of childhood respiratory and atopic outcomes.In the Avon Longitudinal Study of Parents and Children we examined associations of maternal gestational hypertension, hypertension before pregnancy and pre-eclampsia with wheezing at 18 months, wheezing and asthma at 7 years and lung function at 8-9 years, after controlling for potential confounders (n=5322-8734, depending on outcome).Gestational hypertension was not associated with any of the outcomes. There was weak evidence for a positive association between pre-eclampsia and early wheezing (adjusted OR 1.31, 95% CI 0.94-1.82, compared to normotensive pregnancies) and for negative associations between pre-eclampsia and forced expiratory volume in 1 s (adjusted mean difference in sd score -0.14, 95% CI -0.33-0.06) and maximal mid-expiratory flow (-0.15, 95% CI -0.34-0.04). Hypertension before pregnancy was positively associated with wheezing (OR 1.63, 95% CI 1.16-2.31) and asthma (OR 1.34, 95% CI 1.00-1.79).Gestational hypertension is unlikely to be a risk factor for childhood respiratory disorders; hypertension before pregnancy may be a risk factor for childhood wheezing and asthma, but this finding needs replication. Larger studies are needed to confirm whether pre-eclampsia is associated with impaired childhood lung function.

Potential role of folate in pre-eclampsia

Dietary deficiencies of folate and other B vitamin cofactors involved in one-carbon metabolism, together with genetic polymorphisms in key folate-methionine metabolic pathway enzymes, are associated with increases in circulating plasma homocysteine, reduction in DNA methylation patterns, and genome instability events. All of these biomarkers have also been associated with pre-eclampsia. The aim of this review was to explore the literature and identify potential knowledge gaps in relation to the role of folate at the genomic level in either the etiology or the prevention of pre-eclampsia. A systematic search strategy was designed to identify citations in electronic databases for the following terms: folic acid supplementation AND pre-eclampsia, folic acid supplementation AND genome stability, folate AND genome stability AND pre-eclampsia, folic acid supplementation AND DNA methylation, and folate AND DNA methylation AND pre-eclampsia. Forty-three articles were selected according to predefined selection criteria. The studies included in the present review were not homogeneous, which made pooled analysis of the data very difficult. The present review highlights associations between folate deficiency and certain biomarkers observed in various tissues of women at risk of pre-eclampsia. Further investigation is required to understand the role of folate in either the etiology or the prevention of pre-eclampsia.

In utero Head Circumference is Associated with Childhood Allergy

BACKGROUND

Altered fetal growth is known to be associated with allergic disease. Specifically, increased head circumference at birth has been linked to asthma and elevated IgE. However, few studies have examined a link between early fetal anthropometry and allergic disease. The aim of this study was to examine head circumference at mid-gestation in children diagnosed with allergy.

METHODS

This was a retrospective cohort study, comprising pregnancies delivered between 10/2006 and 9/2010 at Nepean Hospital, Australia. Exclusion criteria were illegal drug use, alcohol consumption, gestation <35 weeks, and gestational hypertension. Pregnancy data were sourced from the Nepean Obstetric Database. Atopic diseases (asthma, atopic dermatitis, and IgE-mediated food allergy) were assessed by questionnaire at age 1-5 years. Infants from pregnancies with completed questionnaires, who also had a mid-gestation ultrasound scan, were included (N = 121). Multiple logistic regression techniques were used to model head circumference against the development of allergies.

RESULTS

Smaller head circumference at mid-gestation was associated with increased odds of allergic disease in children aged 1-5 years. A 1 mm smaller head circumference was associated with a 7% increased chance of allergies being later diagnosed, adjusted for gestation (95% CI: 1-14%, p = 0.036). Head circumference at mid-gestation was also inversely correlated with the presence of multiple atopic disease.

CONCLUSION

Smaller mid-gestational head circumference is associated with early childhood allergic disease, which suggests that fetal programing of allergic disease occurs before mid-gestation. This suggests that mediators such as brain-derived neurotrophic factor may be dysregulated early in utero in a milieu, which also predisposes to atopic disease.

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.

Febrile and gynecological infections during pregnancy are associated with a greater risk of childhood eczema

BACKGROUND

Mounting evidence suggests that fetal exposures may exert long-term effects on the function of the skin and of the immune system. This study aimed at assessing whether maternal complications during pregnancy are associated with an increased risk of eczema during childhood.

METHODS

The associations between hypertension/preeclampsia, febrile infections, or gynecological infections during pregnancy and the occurrence of childhood eczema were studied in a population (n = 3907) of children, aged 3-14 yrs, living in Italy. Their parents filled in a standardized questionnaire about the presence of children's eczema and the events that occurred during pregnancy, birth, and the first year of the child's life.

RESULTS

7.7%, 3.8%, and 6.1% of the pregnancies were complicated by hypertension/preeclampsia, febrile infections, and gynecological infections, respectively. The prevalence of eczema was significantly higher in children born to mothers who had experienced febrile (35.5% vs. 22.0%; p < 0.001) or gynecological infections (35.3% vs. 21.6%; p < 0.001) compared with those born to mothers who had not suffered from that specific pregnancy complication, while hypertension/preeclampsia was not significantly associated with childhood eczema. After adjusting for potential confounders, the risk of eczema was significantly higher in children born to mothers who reported febrile infections during the 1st trimester (OR: 2.32; 95% CI: 1.11-4.82) and gynecological infections during the 3rd trimester of pregnancy (OR: 2.73; 95% CI:1.73-4.31).

CONCLUSIONS

Fetal exposure to febrile and gynecological infections might enhance the risk of eczema in the offspring, especially when occurring in specific trimesters of pregnancy. These findings suggest that febrile and gynecological infections might interfere with fetal and perinatal programming of the immune function and skin through different mechanisms.

Fetal-maternal alignment of regulatory T cells correlates with IL-10 and Bcl-2 upregulation in pregnancy

Transplacental immune regulation refers to the concept that during pregnancy, significant cross-talk occurs between the maternal and fetal immune system with potential long-term effects for both the mother and child. In this study, we made the surprising observation that there is a strong correlation of peripheral blood regulatory T (Treg) cells between the mother and the fetus. In contrast, there is no significant Treg cell correlation between paternal fetal dyads (pairs), suggesting that the specific context of pregnancy, rather than the genetic parental similarity to the fetus, is responsible for this correlation. Gene microarray analysis of Treg cells identified a typical IL-10-dependent signature in maternal and fetal Treg cells. In addition, a direct correlation of serum IL-10 protein levels between maternal fetal dyads was observed. Furthermore, we show that maternal serum IL-10 levels correlate with serum estradiol and estriol, implicating hormonal involvement in this alignment. Interestingly, we show that Treg cells possess higher expression of IL-10 receptor α and that Treg cell IL-10 receptor α expression directly correlates with their Bcl-2 expression. Indeed, in vitro data in both humans and mice demonstrate that IL-10 upregulates Bcl-2 specifically in Treg cells but not non-Treg cells. Our results provide evidence for transplacental regulation of cellular immunity and suggest that IL-10 may influence Treg cell homeostasis through its effect on Treg cell Bcl-2 expression. These novel findings have important implications on immune tolerance in pregnancy and beyond in areas of autoimmunity, allergy, and transplantation.

Fetal growth and risk of childhood asthma and allergic disease

Introduction

Early genetic and environmental factors have been discussed as potential causes for the high prevalence of asthma and allergic disease in the western world, and knowledge on fetal growth and its consequence on future health and disease development is emerging.

Objective

This review article is an attempt to summarize research on fetal growth and risk of asthma and allergic disease. Current knowledge and novel findings will be reviewed and open research questions identified, to give basic scientists, immunologists and clinicians an overview of an emerging research field.

Methods

PubMed-search on pre-defined terms and cross-references.

Results

Several studies have shown a correlation between low birth weight and/or gestational age and asthma and high birth weight and/or gestational age and atopy. The exact mechanism is not yet clear but both environmental and genetic factors seem to contribute to fetal growth. Some of these factors are confounders that can be adjusted for, and twin studies have been very helpful in this context. Suggested mechanisms behind fetal growth are often linked to the feto-maternal circulation, including the development of placenta and umbilical cord. However, the causal link between fetal growth restriction and subsequent asthma and allergic disease remains unexplained. New research regarding the catch-up growth following growth restriction has posited an alternative theory that diseases later on in life result from rapid catch-up growth rather than intrauterine growth restriction per se. Several studies have found a correlation between a rapid weight gain after birth and development of asthma or wheezing in childhood.

Conclusion and clinical relevance

Asthma and allergic disease are multifactorial. Several mechanisms seem to influence their development. Additional studies are needed before we fully understand the causal links between fetal growth and development of asthma and allergic diseases.

Early life exposures: impact on asthma and allergic disease

PURPOSE OF REVIEW

To identify and discuss recent studies relating prenatal and early-life environmental exposures to the development of asthma and allergic disease.

RECENT FINDINGS

New studies show that prenatal and early-life stress can alter infant immune profiles, increasing risk for asthma and allergy. Mounting evidence implicates indoor and outdoor air pollution in the origins of allergic disease, while Vitamin D intake and a Mediterranean diet may be protective. The role of early-life fever and infection remain controversial, with recent studies yielding conflicting results and new evidence indicating that previous studies may have been confounded. New studies are increasingly focused on environmental 'imprinting' of the infant gut microbiota, which is a critical determinant of immune system development. Early exposures impacting the intestinal microbiota include mode of delivery, infant diet, and use of antibiotics - factors that are also associated with childhood asthma and allergic disease.

SUMMARY

This overview highlights environmental exposures during the in-utero and ex-utero time periods that are potential stimuli for the early programming of asthma and allergy. Special consideration is given for the potential role of intestinal microbiota. Future studies in this field promise to inform health policy and intervention strategies for the prevention of asthma and allergic disease.

Preterm birth reduces the incidence of atopy in adulthood

BACKGROUND

Immunologic pathways are primed in early life. Preterm birth can influence this process and thereby affect whether a person will have atopy later in life. Previous studies on the effects of preterm birth on atopy in adulthood have been inconclusive and limited to children or subjects born moderately preterm.

OBJECTIVE

Our aim was to compare the incidence of atopy among young adults who were born preterm and at very low birth weight (≤ 1500 g) with that of term-born young adults (control subjects).

METHODS

The study comprised 166 adults who were born preterm and at very low birth weight and 172 control subjects, all of whom were from the Helsinki Study of Very Low Birth Weight Adults. We assessed atopic predisposition at ages 18 to 27 years using skin prick tests for 6 common aeroallergens and measurements of serum concentrations of total IgE and 3 types of allergen-specific (cat, birch, and timothy) IgE. We asked the subjects whether they had been given a diagnosis of asthma or allergic rhinitis or had atopic eczema and analyzed data by using logistic or linear regression, adjusting for potential confounding factors.

RESULTS

The risk for having at least 1 positive reaction on a skin prick test was reduced (adjusted odds ratio, 0.43; 95% CI, 0.23-0.79, P = .007), and the concentration of cat-specific IgE was less (25% less; 95% CI, 43% to 2.3% less; P = .033) in sera from very-low-birth-weight subjects compared with that seen in sera from control subjects. Within the very-low-birth-weight group, those born at an earlier gestational age were less likely to have positive skin prick test reactions (adjusted odds ratio for 1 week, 0.82; 95% CI, 0.68-0.98, P = .029) and less likely to have high levels of allergen-specific IgE. Cumulative incidences of atopic disease were similar between adults of very low birth weight and control subjects.

CONCLUSIONS

Young adults born prematurely and at very low birth weight have a lower incidence of atopy than adults who were born full term. This finding supports the hypothesis that the risk for atopy is determined during early stages of development.