Tumor necrosis factor during pregnancy and at the onset of labor and spontaneous abortion

Behind the Curtain of Abnormal Placentation in Pre-Eclampsia: From Molecular Mechanisms to Histological Hallmarks

Successful human pregnancy needs several highly controlled steps to guarantee an oocyte's fertilization, the embryo's pre-implantation development, and its subsequent implantation into the uterine wall. The subsequent placenta development ensures adequate fetal nutrition and oxygenation, with the trophoblast being the first cell lineage to differentiate during this process. The placenta sustains the growth of the fetus by providing it with oxygen and nutrients and removing waste products. It is not surprising that issues with the early development of the placenta can lead to common pregnancy disorders, such as recurrent miscarriage, fetal growth restriction, pre-eclampsia, and stillbirth. Understanding the normal development of the human placenta is essential for recognizing and contextualizing any pathological aberrations that may occur. The effects of these issues may not become apparent until later in pregnancy, during the mid or advanced stages. This review discusses the process of the embryo implantation phase, the molecular mechanisms involved, and the abnormalities in those mechanisms that are thought to contribute to the development of pre-eclampsia. The review also covers the histological hallmarks of pre-eclampsia as found during the examination of placental tissue from pre-eclampsia patients.

Pre-Eclampsia: From Etiology and Molecular Mechanisms to Clinical Tools-A Review of the Literature

Pre-eclampsia is a severe pregnancy-related complication that manifests as a syndrome with multisystem involvement and damage. It has significantly grown in frequency during the past 30 years and could be considered as one of the major causes of maternal and fetal morbidity and mortality. However, the specific etiology and molecular mechanisms of pre-eclampsia are still poorly known and could have a variety of causes, such as altered angiogenesis, inflammations, maternal infections, obesity, metabolic disorders, gestational diabetes, and autoimmune diseases. Perhaps the most promising area under investigation is the imbalance of maternal angiogenic factors and its effects on vascular function, though studies in placental oxidative stress and maternal immune response have demonstrated intriguing findings. However, to determine the relative importance of each cause and the impact of actions aiming to significantly reduce the incidence of this illness, more research is needed. Moreover, it is necessary to better understand the etiologies of each subtype of pre-eclampsia as well as the pathophysiology of other major obstetrical syndromes to identify a clinical tool able to recognize patients at risk of pre-eclampsia early.

Impact of TNF-α profile in recurrent pregnancy loss pathogenesis: A patient based study from Assam

BACKGROUND

Lacunae exist in understanding the underlying etiology in majority of recurrent pregnancy loss (RPL) cases. Given the significance of regulated immune-modulation in pregnancy, and the central role of pro-inflammatory TNF-α plays in it; this study targeted to appraise the significance of TNF-α profile in RPL pathogenesis in an ethnically distinct population from Assam, India.

METHODS

Term delivery, medically terminated pregnancy (MTP) and RPL cases (based on ASRM criteria) were enrolled with no anatomical and chromosomal abnormalities or pathological infections; and blood and/or placenta/product of conceptus (POC) tissue samples were collected with informed consent. Serum level and tissue level TNF-α expression profile were screened using specific molecular tools, and was correlated with TNF-α -308 G/A genotype; for its association with RPL predisposition.

RESULTS

A significant gestation specific increase in serum TNF-α levels was observed in MTP cases (19.932 ± 4.407 pg/mL) compared to term delivery subjects (p = 0.001), while a comparable levels were observed with RPL cases (22.709 ± 5.833 pg/mL) (p = 0.646). A site specific (POC) increased expression was observed in RPL compared to MTP cases at both at transcript (6.37 ± 3.714 folds) and protein levels. The TNF-α -308 variant genotype was associated with increased predisposition to RPL (OR = 1.721) compared to MTP as well as significantly increased serum TNF-α levels (p = 0.017); especially in subjects with a homozygous TNF-α -308 A/A genotype.

CONCLUSION

Our data emphasizes on the importance of site specific TNF-α expression levels in RPL pathogenesis in the studied population, and underlines its importance in screening, clinical stratification, and therapeutics by molecular targeting using TNF-α inhibitors.

Cytokine imbalance at materno-embryonic interface as a potential immune mechanism for recurrent pregnancy loss

Recurrent pregnancy loss (RPL) is a prominent reproductive disease that distresses about 2%-5% of couples. RPL is the loss of two or more successive spontaneous pregnancies prior to the 20th week of embryo development. The commencement of pregnancy necessitates implantation of the embryo into responsive maternal decidua synchronized with the process of placentation, decidual and myometrial trophoblast incursion as well as refashioning of spiral blood arteries of uterus. The collapse of any of the processes fundamental for pregnancy success may result into an array of pregnancy problems including spontaneous pregnancy loss. Endometrium of human female manufactures an extensive range of cytokines during the proliferative and secretory stage of the menstrual cycle. These endometrial cytokines are thought as major players for making the uterus ready for embryo implantation and placental development during pregnancy. Decidual cytokines regulate the invasion of trophoblast and remodeling of spiral arteries as well as take part in immune suppression to accomplish the pregnancy. Deterrence of maternal rejection of embryo needs a regulated milieu, which takes place essentially at the embryo-maternal interface and the tissues of the uterus. The reasons of RPL remain anonymous in a large number of cases that lead to difficulties in management and severe trauma in couples. Cytokine modulatory therapies have been shown promising for preventing RPL. Further study of novel factors is wanted to establish more effective RPL treatment protocols. The present study aims to review the outcome of cytokine breach at materno-embryonic interface and the efficacy of cytokine modulatory therapies in RPL.

Pleiotropic role of prokineticin 1 in the porcine endometrium during pregnancy establishment and embryo implantation †

Acquisition of endometrial receptivity for embryo implantation is one of the crucial processes during pregnancy and is induced mainly by progesterone and enhanced by conceptus signals. Prokineticin 1 (PROK1) is characterized as a secretory protein with diverse functions in various tissues, including the reproductive tract. PROK1, with its receptor PROKR1, are up-regulated in the porcine endometrium during implantation and in women's receptive endometrium and decidua. However, the function of PROK1 in embryo-maternal communication has still not been fully elucidated. Hence, we hypothesize that PROK1 is involved in endometrial receptivity development and implantation in pigs. In this study, using the porcine in vivo model of intrauterine infusions of estradiol-17β (E2) and prostaglandin E2 (PGE2), we revealed that these hormones elevated endometrial expression of PROK1 and PROKR1 mRNA, respectively. Moreover, E2, acting synergistically with PGE2, increased PROKR1 protein expression. We also evidenced that PROK1-PROKR1 signaling induced expression of following genes and/or proteins CCN2, CDH13, FGF2, NFATC2, ANGPT1, ANGPT2, CDH1, MUC4, SPP1, IFNG, IL6, LIF, LIFR, TNF, TGFB3, and FGF9, as well as phosphorylation of PTK2 and secretion of IL6 and IL11 by endometrial explants in vitro. Ingenuity pathway analysis revealed that functions associated with the PROK1-regulated genes/proteins include cell-to-cell contact, cell attachment, migration and viability, differentiation of epithelial tissue, leukocyte migration, inflammatory response, angiogenesis, and vasculogenesis. Summarizing, our study suggests that PROK1 acts pleiotropically as an embryonic signal mediator that regulates endometrial receptivity by increasing the expression of the genes and proteins involved in implantation and pregnancy establishment in pigs.

Preeclampsia before fetal viability in women with primary antiphospholipid syndrome- materno-fetal outcomes in a series of 7 cases

INTRODUCTION

Preeclampsia complicates about 10-17 % of pregnancies with antiphospholipid syndrome (APS). It is often severe and might occur sometimes at early gestation. The development of preeclampsia before fetal viability is a huge challenge for obstetricians and demands an intensive discussion regarding the therapeutical options.

PATIENTS AND METHODS

We retrospectively reviewed the data of 7 women with primary APS who developed preeclampsia before 24 weeks of gestation. Plasma exchange had been performed in four of the cases and two women received corticosteroids. One of the women had received 20 mg of pravastatin daily, starting at 18 weeks of gestation. Neonatal outcome was: live birth in four cases and IUFD in three cases. The main pediatric complications were noted in a 28-week-old premature born boy, who developed severe IRDS and thrombocytopenia. At the present time, the boy continues to have a retarded status.

DISCUSSION

This retrospective analysis revealed that women with APS can develop severe preeclampsia even before 20 weeks of gestation. Several management options for prolongation of pregnancy such as plasma exchange, pravastatin, LMHW, hydroxychloroquine/HCQ, or TNF-alpha blocker should be discussed with the patients. Optimal management of preeclampsia before 24 weeks of gestation usually depends on weighing the maternal and fetal complications from expectant management with prolongation of pregnancy versus the predominant fetal and neonatal risks of extreme prematurity from "aggressive" management with immediate delivery.

Does tumour necrosis factor alpha-induced cyclooxygenase-2 expression lead to spontaneous abortion in Chlamydia trachomatis-infected women

Cytokines might be involved in spontaneous abortion by triggering inflammatory mediators (Cyclooxygenases (Cox)) leading to spontaneous abortion in Chlamydia trachomatis (Ct)-infected women. Study aimed to quantitate the expression of pro-inflammatory cytokines (TNF-α, IFN-γ, IL-8) and Cox-2 in endometrial curettage tissue (ECT) of Spontaneous Aborters (SA). SA (n = 135) and 120 age-matched controls were enrolled from SJH, New Delhi, India. PCR was performed for detection of Ct MOMP gene (537 bp) in ECT. mRNA expression of pro-inflammatory cytokines and Cox-2 was assessed by real-time qPCR. Data was statistically evaluated. 14.8% SA were diagnosed as Ct-positive. Elevated expression of TNF-α, IFN-γ, IL-8 and Cox-2 was observed in Ct-infected SA. Ct-positive recurrent aborters showed significantly higher cytokine expression. Significant positive correlation was found between expression of Cox-2 and TNF-α in infected SA. Data suggested an increased expression of Th-1 cytokines, particularly TNF-α that induced Cox-2 expression in ECT, leading to spontaneous abortion in Ct-infected pregnant women.

Neonatal outcomes of children born to mothers on biological agents during pregnancy: State of the art and perspectives

Biologic disease-modifying anti-rheumatic drugs (bDMARDs) are used in pregnant patients with rheumatic diseases. Long-term follow-up data about newborns exposed to bDMARDs during pregnancy are however scarce. Here we summarize the published evidence and available recommendations for use of bDMARDs during pregnancy. We analyse clinical features at birth and at follow-up of 84 children, including: 16 consecutive children born to mothers with autoimmune diseases exposed to bDMARDs in utero; 32 children born to mothers with autoimmune diseases who did not receive bDMARDs; 36 children born to healthy mothers. In our monocentric cohort, children born to mothers with autoimmune diseases had lower gestational age at birth compared to those born to healthy mothers, independently of exposure to bDMARDs. At multivariate analysis, prematurity was an independent predictor of the need for antibiotic treatment, but not for hospitalisation or neonatal intensive care unit (ICU) stay during the neonatal period. Exposure to bDMARDs during pregnancy does not seem to interfere with post-natal development up to infancy. Prospective studies are needed in larger cohorts of pregnant patients to confirm that bDMARDs do not have a negative impact on psychomotor achievements in newborns.

Molecular and biochemical investigations of key antioxidant/oxidant molecules in Saudi patients with recurrent miscarriage

The present study was undertaken to: i) Determine the levels of oxidative stress (OS) markers, malondialdehyde (MDA), superoxide anions (SOA) and hydrogen peroxide (H₂O₂), in both plasma and placental tissues of recurrent miscarriage (RM) patients in comparison with those of healthy pregnant (HP) and non-pregnant (NP) women; ii) determine the levels of enzymatic antioxidants [glutathione peroxidase (GPx), glutathione reductase (GSR), superoxide dismutase (SOD) and catalase (CAT)], and non-enzymatic antioxidant micronutrients [selenium (Se), zinc (Zn), copper (Cu) and manganese (Mn)] in both plasma and placental tissues of RM patients, in comparison with those of HP and NP women; iii) profile differential expression levels of selected antioxidant and apoptosis-related genes in the placental tissues of RM cases, in relation to those of HP women of matched gestational age, using reverse transcription-quantitative polymerase chain reaction (RT-qPCR). The results revealed highly significant increases of all investigated OS markers in plasma and placental tissues of RM patients compared with those of HP women. Moderate, but significant, increases of OS markers were observed in the plasma of HP patients in relation to those of NP women. The activities of antioxidant enzymes exhibited statistically significant decreases in both plasma and placental tissues of RM patients compared with those of HP women. The significantly reduced level of antioxidant enzymes was also evident in the plasma of HP women as compared with those of NP women. Results of RT-qPCR assays clearly indicated that the expression level of apoptosis-related genes [tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) and S100A8], and pro-inflammatory cytokine genes [tumor necrosis factor-α (TNF-α), interleukin (IL)-6 and IL-8] were significantly upregulated in placental tissue of RM cases in relation to those of HP subjects. By contrast, mRNA transcriptional levels of key antioxidant genes (GPx, SOD, GSR and CAT) were found to be significantly reduced in placental tissue of RM patients in comparison to those of HP women. In conclusion, our data highlight a plausible cause-effect association between the observed increase in placental OS level and depletion of the activity of antioxidant enzymes. This suggests that OS is a contributing factor in the pathogenesis of idiopathic RM.

Prophylactic Effects of Bee Venom Phospholipase A2 in Lipopolysaccharide-Induced Pregnancy Loss

Spontaneous abortion represents a common form of embryonic loss caused by early pregnancy failure. In the present study, we investigated the prophylactic effects of bee venom phospholipase A2 (bvPLA2), a regulatory T cell (Treg) inducer, on a lipopolysaccharide (LPS)-induced abortion mouse model. Fetal loss, including viable implants, the fetal resorption rate, and the fetal weight, were measured after LPS and bvPLA2 treatment. The levels of serum and tissue inflammatory cytokines were determined. To investigate the involvement of the Treg population in bvPLA2-mediated protection against fetal loss, the effect of Treg depletion was evaluated following bvPLA2 and LPS treatment. The results clearly revealed that bvPLA2 can prevent fetal loss accompanied by growth restriction in the remaining viable fetus. When the LPS-induced abortion mice were treated with bvPLA2, Treg cells were significantly increased compared with those in the non-pregnant, PBS, and LPS groups. After LPS injection, the levels of proinflammatory cytokines were markedly increased compared with those in the PBS mouse group, while bvPLA2 treatment showed significantly decreased TNF-α and IFN-γ expression compared with that in the LPS group. The protective effects of bvPLA2 treatment were not detected in Treg-depleted abortion-prone mice. These findings suggest that bvPLA2 has protective effects in the LPS-induced abortion mouse model by regulating Treg populations.

Risk of preterm delivery and small-for-gestational-age births in women with autoimmune disease using biologics before or during pregnancy: a population-based cohort study

OBJECTIVES

To assess the risk of preterm delivery and small-for-gestational-age (SGA) births in women with autoimmune diseases using biologics before or during pregnancy.

METHODS

Using population-based administrative data in British Columbia, Canada, women with one or more autoimmune diseases who had pregnancies between 1 January 2002 and 31 December 2012 were included. Exposure to biologics was defined as having at least one biologic prescription 3 months before or during pregnancy. Each exposed pregnancy was matched with five unexposed pregnancies using high-dimensional propensity scores (HDPS). Logistic regression modelling was used to evaluate the association between biologics use and preterm delivery and SGA.

RESULTS

There were 6218 women with 8607 pregnancies who had an autoimmune disease diagnosis; of which 109 women with 120 pregnancies were exposed to biologics 3 months before or during pregnancy. In unadjusted analyses, the ORs for the association of biologics exposure with preterm deliveries were 1.64 (95% CI 1.02 to 2.63) and 1.34 (95% CI 0.72 to 2.51) for SGA. After HDPS matching with 600 unexposed pregnancies, the ORs for the association of biologics exposure and preterm deliveries were 1.13 (95% CI 0.67 to 1.90) and 0.91 (95% CI 0.46 to 1.78) for SGA. Sensitivity analyses using HDPS deciles, continuous HDPS covariate or longer exposure window did not result in marked changes in point estimates and CIs.

CONCLUSIONS

These population-based data suggest that the use of biologics before and during pregnancy is not associated with an increased risk of preterm delivery or SGA births.

Association of organochlorine pesticides with the mRNA expression of tumour necrosis factor-alpha (TNF-α) & cyclooxygenase-2 (COX-2) genes in idiopathic preterm birth

Background & objectives:

Preterm birth (PTB) is an important cause of prenatal death, neonatal morbidity and mortality and adult illness. Increased inflammation occurs in normal parturition, and inflammatory cytokines and oxidative stress are found to be higher in PTB cases. The present study was planned to investigate the association of organochlorine pesticides (OCPs) with mRNA expression of inflammatory pathway genes such as tumour necrosis factor-alpha (TNF-α) and cyclooxygenase-2 (COX-2) in preterm delivery (PTD) cases.

Methods:

Maternal blood samples of PTD (n=30) cases and equal number of term delivery (n=30) were collected at the time of labour. Women occupationally exposed to OCPs and other high risk factors such as anaemia, hypertension, bacterial vaginosis, renal and heart disease, diabetes, etc. were excluded. The OCP levels were estimated by gas chromatography, and mRNA expressions of TNF-α and COX-2 genes were analysed using real-time PCR (qPCR).

Results:

Significantly higher levels of β-HCH (beta-hexachlorocyclohexane, 95% CI=2.08-4.633, P=0.001), p’p’-DDE (para, para-dichlorodiphenyldichloroethylene, 95% CI=0.546-2.551, P=0.003), and o’p’-DDD (ortho, para-dichlorodiphenyldichloroethane, 95% CI=0.004-0.690, P=0.047) were observed in maternal blood of PTB cases as compared to term delivery. The mRNA expressions of COX-2 and TNF-α genes were 3.13 and 2.31 folds higher in PTB cases in comparison to term delivery. Linear positive correlations were observed between period of gestation (POG) and ΔCt of COX-2 and TNF-α genes.

Interpretation & conclusions:

Environmental factors such as OCPs may be associated with inflammatory events showing gene-environment interaction in PTB cases. Evaluating the molecular control of inflammation along with gene environment interaction may be used as a model to explore the aetiology of idiopathic PTB cases and may be considered for the prognosis of adverse reproductive outcomes.

Relationship between hair and salivary cortisol and pregnancy in women undergoing IVF

Evidence for an association between cortisol and clinical pregnancy in women undergoing In Vitro Fertilisation (IVF) is mixed with previous studies relying exclusively on short term measures of cortisol in blood, saliva, urine, and/or follicular fluid. Hair sampling allows analysis of systemic levels of cortisol over the preceding 3-6 months. The present study sought to explore the relationship between cortisol and clinical pregnancy outcome in women undergoing IVF utilising multiple indices of cortisol derived from both saliva and hair measured prior to commencing gonadotrophin treatment. A total of 135 women (mean age 34.5 SD+/-4.8) were recruited from an English fertility clinic (December 2012-April 2014) 60% of whom became pregnant (n=81). Salivary cortisol data were obtained over two days: upon awakening, 30min post awakening, and at 22:00. A subsample (n=88) of the women providing salivary samples were approached consecutively to provide hair samples for the measurement of cortisol. Independent Logistic regression analyses revealed that salivary cortisol measures including cortisol awakening response (CAR) (p=0.485), area under the curve with respect to ground (AUCg) (p=0.527), area under the curve with respect to increase (AUCi) (p=0.731) and diurnal slope (p=0.889) did not predict clinical pregnancy. In contrast, hair cortisol concentrations significantly predicted clinical pregnancy (p=0.017). Associations between hair cortisol and clinical pregnancy remained when controlling for accumulations of salivary cortisol (p=0.034) accounting for 26.7% of the variance in pregnancy outcome. These findings provide preliminary evidence that longer term systemic cortisol may influence reproductive outcomes; and in turn suggests that interventions to reduce cortisol prior to commencing IVF could improve treatment outcomes.

A Tumor Necrosis Factor—α Promoter Polymorphism and Pregnancy Complications: Results of a Prospective Cohort Study in 1652 Pregnant Women

The purpose of this article is to investigate the frequency of the tumor necrosis factor-alpha (TNF-alpha) -308 G/A single nucleotide polymorphism in women with intrauterine fetal death, preeclampsia, preterm delivery, and small-for-gestational-age (SGA) infants. In a prospective cohort study, DNA from 1652 consecutive pregnant women was analyzed for TNF-alpha -308 G/A by polymerase chain reaction. Women who developed at least 1 of the predefined pregnancy complications were used as cases and compared to women without pregnancy complications. Of 1652 women, 268 (16.2%) developed at least 1 pregnancy complication. TNF-alpha -308 G/A allele frequencies (G: 463/536 [86%] and A: 73/536 [14%] vs G: 2366/2768 [85%] and A: 402/2768 [15%], respectively; P = .6; odds ratio [OR], 0.93; 95% confidence interval [CI], 0.69-1.25) and genotype distributions (G/G+G/A: 259/268 [97%] and A/A 9/268 [3%] vs G/G+G/A: 1352/1384 [98%] and A/A 32/1384 [2%], respectively; P = .4; OR, 0.20; 95% CI, 0.002-14.81) were not significantly different between cases and controls. The authors observed no statistically significant difference in TNF-a -308 G/A genotype distributions comparing controls and women with intrauterine fetal death, preeclampsia, preterm delivery <34 weeks' gestation, preterm delivery >34 weeks' gestation, SGA infants <3rd percentile, and SGA infants of the 4th to 10th percentile. TNF-alpha -308 G/A is not a genetic marker for identifying women at increased risk of common pregnancy complications.

Adaptation of the inflammatory immune response across pregnancy and postpartum in Black and White women

Pregnancy is a period of considerable physiological adaption in neuroendocrine, cardiovascular, as well as immune function. Understanding of typical changes in inflammatory immune responses during healthy pregnancy is incomplete. In addition, despite considerable racial difference in adverse pregnancy outcomes, data are lacking on potential racial differences in such adaptation. This repeated measures prospective cohort study included 37 Black and 39 White women who provided blood samples during early, mid-, and late pregnancy and 8-10 weeks postpartum. Peripheral blood mononuclear cells were incubated with lipopolysaccharide (LPS) for 24h and supernatants assayed by electrochemiluminescence to quantify interleukin(IL)-6, tumor necrosis factor(TNF)-α, IL-1β, and IL-8 production. While no changes were observed in IL-8 production over time, significant increases in IL-6, TNF-α, and IL-1β production were observed from early to late pregnancy, with subsequent declines approaching early pregnancy values at postpartum (ps<0.05). Overall, inflammatory response patterns were highly similar among Black versus White women. However, Black women had greater TNF-α production during mid-pregnancy (p=0.002) and marginally lower IL-1β production at postpartum (p=0.054). These data show a clear trajectory of change in the inflammatory immune response across pregnancy and postpartum. In this cohort of generally healthy women, Black and White women exhibited minimal differences in LPS-stimulated cytokine production across the perinatal period. Future prospective studies in Black and White women with healthy versus adverse outcomes (e.g., preeclampsia, preterm birth) would inform our understanding of the potential role of immune dysregulation in pregnant women and in relation to racial disparities in perinatal health.

A proposed bio-panel to predict risk for spontaneous preterm birth among African American women

Preterm birth (PTB), or birth prior to 37 weeks gestation, impacts 11.5% of U.S. deliveries. PTB results in significant morbidity and mortality among affected children and imposes a large societal financial burden. Racial disparities in PTB are alarming. African American women are at more than 1.5 times the risk for PTB than white women. Unfortunately, the medical community's ability to predict who is at risk for PTB is extremely limited. History of a prior PTB remains the strongest predictor during a singleton gestation. Cervical length and fetal fibronectin measurement are helpful tools. However, usefulness is limited, particularly among the 95% of U.S. women currently pregnant and lacking a history of PTB. Therefore, preventive therapies do not reach a great number of women who may benefit from them. This manuscript, in response to the pressing need for predictors of PTB risk and elimination of racial disparities in PTB, presents a proposed bio-panel for use in predicting risk for spontaneous PTB among African American women. This bio-panel, measured each trimester, includes stimulated production of interleukin (IL)-1β, tumor necrosis factor (TNF)-α, IL-1 receptor antagonist (Ra), soluble(s) TNF receptor(R) 1, and sTNFR2, and cortisol responsiveness. We hypothesize that greater IL-1β and TNF-α production, decreased IL-1Ra, sTNFR1, and sTNFR2 production, and decreased cortisol responsiveness at each time point as well as a more expedient alignment with this unfavorable profile over time will be associated with PTB. The choice to focus on inflammatory parameters is supported by data highlighting a crucial role for inflammation in labor. Specific inflammatory mediators have been chosen due to their potential importance in preterm labor among African American women. The bio-panel also focuses on inflammatory regulation (i.e., cytokine production upon ex vivo stimulation), which is hypothesized to provide insight into potential in vivo leukocyte responses and potential for initiation of a preterm inflammatory cascade. Production of receptor antagonists is also considered, as pro-inflammatory mediator effects can be greatly influenced by their balance with respective antagonists. Finally, leukocyte responsiveness to cortisol is included as a measure of cortisol's ability to convey anti-inflammatory signals. The development of a bio-panel predictive of risk for spontaneous PTB among African American women would represent a significant advancement. Available preventive therapies, namely progesterone supplementation, could be delivered to women deemed at risk. Further, the identification of biological predictors of PTB may uncover novel targets for preventive therapies.

Pregnancy and the Immune System: General Overview and the Gastroenterological Perspective

Pregnancy represents a unique immune tolerant condition that cannot be attributed merely to generalized immunosuppression. A variety of mechanisms have been described, ranging from the non-self recognition, immunomodulation of specific inflammatory cell populations and a Th2-directed shift of the immune response, which are mediated by both localized and systemic mediators. Furthermore, an inflammatory response directed toward the conceptus is no longer considered an obligatory deleterious response; instead, it is considered an important factor that is necessary for normal growth and development. These immunomodulatory changes during pregnancy may also affect concurrent conditions and alter the course of inflammatory diseases. Herein, we review the main immunomodulatory changes that occur during pregnancy and their effect on coexisting inflammatory conditions, with a specific focus on gastrointestinal disorders.

Pregnancy morbidity in antiphospholipid syndrome: what is the impact of treatment?

Women with persistently circulating antiphospholipid antibodies (aPL) have a higher incidence of recurrent abortions, fetal losses, pre-eclampsia, and placental insufficiency. Current treatment of patients with antiphospholipid syndrome (APS) during pregnancy with heparin and aspirin can act by preventing clot formation and improving live birth rates, but other obstetric morbidities remain high, especially in patients with a history of thrombotic events. In addition to the classical thrombotic placental events, other factors involving inflammation and complement activation seem to play a role in certain complications. In this article, we will review how medications interfere in the pathogenic mechanisms of APS, discuss the impact of current recommended treatment on pregnancy morbidity, and analyze new promising therapies.

Protective effects of baicalin on decidua cells of LPS-induced mice abortion

The study was carried out to investigate the protective effects of Baicalin on decidual cells of LPS-induced abortion mice. In the in vitro experiment, the decidual cells were cultured by uterus tissue mass cultivation sampled at day 6 of pregnancy, and gradient concentrations of LPS were used to determine the optimal LPS concentration of the injured decidual cells model. The injured decidual cells were treated with Baicalin (4 μg/mL) to determine the protective role of Baicalin. In the in vivo experiment, lipopolysaccharide (LPS) was injected intravenously via the tail vein to induce abortion at day 6 of pregnancy, and the mice were given different concentrations of Baicalin by oral gavage consecutively at days 7 to 8 of pregnancy. On day 9 of gestation, the mice were sacrificed. The TNF and progesterone contents in the serum were assayed by ELISA. The results clearly revealed that Baicalin can prevent the injury to decidual cells from LPS dose dependently, TNF was decreased significantly (P < 0.01) compared to LPS group, and there was no effect on the progesterone. These findings suggest that Baicalin has protective effects on the injured decidual cells in the pregnant mice.

Tumor necrosis factor-α inhibitor therapy and fetal risk: A systematic literature review

Tumor necrosis factor-α inhibitors (anti-TNFs) are effective in the treatment of inflammatory bowel disease (IBD) recalcitrant to conventional medical therapy. As the peak incidence of IBD overlaps with the prime reproductive years, it is crucial to establish pharmacologic regimens for women of childbearing age that achieve effective disease control without posing significant fetal harm. A systematic literature review was performed to identify all human studies with birth outcomes data after maternal exposure to infliximab, adalimumab, or certolizumab pegol within 3 mo of conception or during any trimester of pregnancy. Live births, spontaneous abortions or stillbirths, preterm or premature births, low birth weight or small for gestational age infants, and congenital abnormalities were recorded. Fifty selected references identified 472 pregnancy exposures. The subsequent review includes general information regarding anti-TNF therapy in pregnancy followed by a summary of our findings. The benefits of biologic modalities in optimizing disease control during pregnancy must be weighed against the potential toxicity of drug exposure on the developing fetus. Although promising overall, there is insufficient evidence to prove absolute safety for use of anti-TNFs during pregnancy given the limitations of available data and lack of controlled trials.

Side effects of TNF-α blockers in patients with psoriatic arthritis: evidences from literature studies

Psoriatic arthritis is an inflammatory rheumatic disorder, which occurs in patients with skin and/or nail psoriasis. In psoriatic arthritis, the importance of biologic mediators modulating inflammatory reaction, such as tumor necrosis factor, and the knowledge on their role in the pathogenesis of psoriatic arthritis influence the therapeutic choices. In the last years, the introduction of biologic drugs has greatly changed the treatment of psoriasis and psoriatic arthritis. In fact, tumor necrosis factor-α blockers demonstrated an effective action in the treatment of both skin and joint manifestations of psoriatic arthritis, but they have some adverse effects. The aim of this review is to revisit the literature data on adverse effects of tumor necrosis factor-α blockers in patients with psoriatic arthritis.

Review article: a decision-making algorithm for the management of pregnancy in the inflammatory bowel disease patient

BACKGROUND

Inflammatory bowel disease affects patients who are in their reproductive years. There are many questions regarding the management of IBD patients who are considering or who are already pregnant. These include the effect of the disease and the medications on fertility and on the pregnancy outcome.

AIM

To create an evidence-based decision-making algorithm to help guide physicians through the management of pregnancy in the IBD patient.

METHODS

A literature review using phrases that include: 'inflammatory bowel disease', 'Crohn's disease', 'ulcerative colitis', 'pregnancy', 'fertility', 'breast feeding', 'delivery', 'surgery', 'immunomodulators', 'azathioprine', 'mercaptopurine', 'biologics', 'infliximab', 'adalimumab', 'certolizumab'.

CONCLUSIONS

The four decision-making nodes in the algorithm for the management of pregnancy in the IBD patient, and the key points for each one are as follows: (i) preconception counselling - pregnancy outcome is better if patients remain in remission during pregnancy, (ii) contemplating pregnancy or is already pregnant - drugs used to treat IBD appear to be safe during pregnancy, with the exception of methotrexate and thalidomide, (iii) delivery and (iv) breast feeding - drugs used to treat IBD appear to be safe during lactation, except for ciclosporin. Another key point is that biological agents may be continued up to 30 weeks gestation. The management of pregnancy in the IBD patient should be multi-disciplinary involving the patient and her partner, the family physician, the gastroenterologist and the obstetrician.

Molecular mechanisms of preeclampsia

Preeclampsia is one of the leading causes of maternal morbidity/mortality. The pathogenesis of preeclampsia is still under investigation. The aim of this paper is to present the molecular mechanisms implicating in the pathway leading to preeclampsia.

The safety of etanercept for the treatment of plaque psoriasis

Effective treatment with etanercept results from a congregation of immunological signaling and modulating roles played by tumor necrosis factor-alpha (TNF-alpha), a pervasive member of the TNF super-family of cytokines participating in numerous immunologic and metabolic functions. Macrophages, lymphocytes and other cells produce TNF as part of the deregulated immune response resulting in psoriasis or other chronic inflammatory disorders. Tumor necrosis factor is also produced by macrophages and lymphocytes responding to foreign antigens as a primary response to potential infection. Interference with cytokine signaling by etanercept yields therapeutic response. At the same time, interference with cytokine signaling by etanercept exposes patients to potential adverse events. While the efficacy of etanercept for the treatment of psoriasis is evident, the risks of treatment continue to be defined. Of the potential serious adverse events, response to infection is the best characterized in terms of physiology, incidence, and management. Rare but serious events: activation of latent tuberculosis, multiple sclerosis, lymphoma, and others, have been observed but have questionable or yet to be defined association with therapeutic uses of etanercept. The safe use of etanercept for the treatment of psoriasis requires an appreciation of potential adverse events as well as screening and monitoring strategies designed to manage patient risk

Association of Insulin Resistance with Serum Interleukin-6 and TNF-α Levels During Normal Pregnancy

Overview:

The purpose of this study was to evaluate the role of Tumor Necrosis Factor-α (TNF-α) in insulin resistance (IR) during normal pregnancy.

Approach:

This cross sectional study was carried out on 86 healthy pregnant women including 26, 23 and 37 individuals in the 1st, 2nd and 3rd trimesters, respectively, and in 21 healthy non pregnant women. Serum TNF-α concentration was measured by Enzyme Linked Immunosorbent Assay (ELISA) method.

Results:

There were significant differences between serum TNF-α and IL-6 levels in pregnant women as compared with maternal healthy controls. There was significant correlation between gestational age and Body Mass Index (BMI) (r = 0.28, P = 0.01). There was no significant correlation between gestational age and insulin resistance (IR). We also did not find correlations between IR and TNF-α and IR and IL-6 in pregnant women.

Conclusion:

In conclusion, our findings suggest that TNF-α and IL-6 are not greatly contributed to pregnancy induced insulin resistance in normal pregnancy.

Cytokines in recurrent pregnancy loss

BACKGROUND

Recurrent pregnancy loss (RPL) is defined as the occurrence of three or more consecutive miscarriages prior to 20 weeks gestation. Exaggerated maternal immune response to fetal antigens has been proposed to be one of the mechanisms underlying recurrent pregnancy loss.

METHOD

A comprehensive literature search was conducted from the websites of the National Library of Medicine (http://www.ncbl.nlm.nih.gov) and Pubmed Central, the US National Library of Medicine's digital archive of life sciences literature (http://www.pubmedcentral.nih.gov/). The data was assessed from books and journals that published relevant articles in this field.

RESULT

In normal pregnancy, tolerance of the genetically incompatible fetus by the maternal immune system depends on the interactions of an array of cytokines secreted by maternal and fetal cells at the site of implantation. Earlier research indicated that altered immunity in RPL is dominated by the Th1/Th2 hypothesis, which proposed that the fetus escapes maternal-derived T-cell responses through skewing the Th0 differentiation toward Th2 pathway which dampens pro-inflammatory Th1-type immunity. Recent studies indicate the role of proinflammatory Th17 cells and immunoregulatory Treg cells in RPL in addition to Th1/Th2 interactions.

CONCLUSION

Cytokines form a complex regulatory network which maintains homeostasis between the fetal unit and the maternal immune system. If this delicate balance is adversely affected, immunoregulatory mechanisms may be insufficient to restore homeostasis and this may lead to pregnancy failure.

Anti-TNF therapy and pregnancy outcomes in women with inflammatory arthritis

Women suffering from inflammatory arthritis may experience a change in disease activity during and after pregnancy. Although the majority will improve, some women may need to continue therapy throughout pregnancy and/or in the lactation period. Since certain disease-modifying antirheumatic drugs have proven to be human teratogens, treatment is limited in these women. Anti-TNF agents fall within the US FDA category B concerning fetal risk, indicating that no adequate and well-controlled studies have been conducted in pregnant or lactating women. However, in the last decade, numerous case series and case reports of pregnancies exposed to anti-TNF therapy have accumulated in the literature. Since these agents may constitute an important therapeutic alternative in pregnant women facing persistent or increased disease activity, we propose a review of the available information on the safety of anti-TNF agents in pregnancy and lactation.

Profile of peripheral blood neutrophil cytokines in diabetes type 1 pregnant women and its correlation with selected parameters in the newborns

PROBLEM

Interleukin (IL)-12, IL-10, tumor necrosis factor-alpha (TNF-alpha), IL-6 and IL-8 alter as pregnancy progresses, implying continuous immune regulation associated with the maintenance of pregnancy. We aimed to evaluate the peripheral blood neutrophil-derived production of these cytokines in the course of pregnancy complicated by type 1 diabetes.

METHOD

of study These parameters were measured in samples from healthy non-pregnant (C), diabetic non-pregnant (D), healthy pregnant (P) and pregnant diabetic (PD) women.

RESULTS

Neutrophil-derived secretion of TNF-alpha and IL-12 increased along with progression of pregnancy in PD and P groups. The concentration of IL-10 from lipopolysaccharide (LPS)-stimulated neutrophils increased during the course of uncomplicated pregnancy but decreased in diabetic pregnancy. Concentration of IL-8 decreased with the advancing gestational age in P and PD groups. LPS-stimulated neutrophil-derived IL-6 concentration increased only in PD patients.

CONCLUSION

Our results show that diabetes creates pro-inflammatory environment thus potentially influencing the outcome of pregnancy. We conclude that neutrophil-derived cytokine production could contribute to the complications seen in pregnant women with type 1 diabetes.

Inflammatory bowel disease and pregnancy: evidence, uncertainty and patient decision-making

Inflammatory bowel disease (IBD) often affects women during their child-bearing years. Management of a pregnant IBD patient, or a patient contemplating pregnancy, poses unique challenges and can be quite daunting. Knowledge of the basic interplay among disease, normal host physiology and pregnancy is vital to managing these patients. One of the most important advances in the management of IBD over the past decade has been the finding that normal pregnancy outcomes can be achieved when a woman enters the pregnancy in remission. New insights into the safety of a wider spectrum of drugs in these patients has allowed for increased success in IBD management. The evidence supporting medical interventions including biological therapy such as antibodies to tumour necrosis factor agents is reviewed. Once the treating physician understands this complex relationship, management of the pregnant IBD patient can often become a rewarding experience.

Cytokine gene polymorphisms in recurrent spontaneous abortions: a comprehensive review

PROBLEM

Cytokine gene polymorphism studies in women with recurrent spontaneous abortion (RSA) are reviewed to provide comprehensive understanding and a direction for the future investigation.

METHOD OF STUDY

A search of PubMed was made to identify the published data between 2001 and 2007 regarding RSA and cytokine gene polymorphisms.

RESULTS

Either allele and/or genotype frequencies of the following polymorphisms were reported to be significantly different between women with RSA and controls: IFN-gamma +874A-->T, TA (P = 0.01), AA (P = 0.04); IL-6, -634C-->G CG/GG (P = 0.026); IL-10, -592C-->A CC (P = 0.016); IL-1B -511C (P = 0.035), -31T (P = 0.029); IL-1RA, IL1RN*2 (P = 0.002), and IL1RN*3 (P = 0.002). None of these studies was repeatedly reported by others to be significantly different. Among these, four cytokine polymorphisms (IFN-gamma, +874A-->T; IL-1B -511C; IL-1RA, IL1RN*2, IL1RN*3) were refuted by others and rest of them were studied once.

CONCLUSION

Multiple cytokine polymorphisms were reported to be associated with RSA. However, a majority of studies were not confirmed by other investigators or refuted by others. Inconsistent study results might be related to: (i) the production of these cytokines is partly under genetic controls and other factors affect cytokine levels; (ii) ethnic background, environmental factors, and selection criteria for study populations are different and (iii) the possibilities exist that multiple cytokine gene polymorphisms or other genes in linkage disequilibrium may play a role in RSA.

Tumor necrosis factor-alpha and oxidant status are essential participating factors in unexplained recurrent spontaneous abortions

BACKGROUND

Many factors have been implicated in the pathogenesis of unexplained recurrent spontaneous abortion (URSA). The current study was conducted to determine the possible role of antioxidant status and tumor necrosis factor-alpha (TNF-alpha) in URSA.

METHODS

Reduced glutathione (GSH), glutathione reductase (GSH-R), glutathione peroxidase (GSH-PX), catalase (CAT), superoxide dismutase (SOD), nitric oxide (NO), malondialdehyde (MDA) and TNF-alpha were assayed in women suffering unexplained first-trimester abortions. Two groups were included, the first represented by 24 women with URSA (number of abortions 3-5) and the second included 16 women with URSA (number of abortions >5). The control group included 20 women within their first trimester of pregnancy and 20 non-pregnant healthy females within their follicular phase.

RESULTS

We observed that the antioxidant levels measured were significantly lower in URSA groups than in the control group (p<0.05 for each comparison). Higher TNF-alpha, MDA and NO production were detected in URSA groups compared to controls (p<0.05 for each comparison). URSA 3-5 was associated with significantly higher levels of antioxidants and lower levels of TNF-alpha compared to levels in URSA >5.

CONCLUSIONS

Impaired antioxidant defense and an increase in oxidative reactive species may be responsible for recurrent abortion due to possible damage produced by their generation. In addition, the level of TNF-alpha apparently contributes to the pathogenesis of URSA.

Elevated circulating IL-1beta and TNF-alpha, and unaltered IL-6 in first-trimester pregnancies complicated by threatened abortion with an adverse outcome

The purpose of the present study was to examine the profile of selected proinflammatory cytokines in maternal serum of first-trimester pregnancies complicated by threatened abortion (TACP) and its relevance to obstetric outcome. Serum levels of Th1-type cytokines interleukin-1β (IL-1β), tumor necrosis factor alpha (TNF-alpha), and Th2-type cytokine interleukin 6 (IL-6) were measured, by ELISA, in 22 women with TACP and adverse outcome at admission (group A) and compared with the corresponding levels of 31 gestational age-matched women with TACP and successful outcome at admission (group B1) and discharge (group B2) and 22 gestational age-matched women with first-trimester uncomplicated pregnancy (group C) who served as controls. Mann-Whitney U or Wilcoxon test was applied as appropriate to compare differences between groups. IL-1β and TNF-alpha were detected with significantly higher levels in group A, compared to all other groups. On the contrary, IL-6 levels were detected with no significant difference among all the other groups studied. It is concluded that in first-trimester TACP with adverse outcome, a distinct immune response, as reflected by elevated maternal IL-1β, TNF-alpha, and unaltered IL-6 levels, is relevant to a negative obstetric outcome.

Cytokines in recurrent pregnancy loss

Cytokines seem to play a critical role in the pathogenesis of unexplained recurrent pregnancy loss (RPL). Th1 cytokines have been shown to exert deleterious effects on pregnancy, inhibiting foetal growth and development. On the other hand, Th2 cytokines have been associated with successful pregnancy. The purpose of this study was to evaluate cytokine production in women with RPL. The studied group comprised 29 women with RPL, with at least three consecutive spontaneous abortions. The control group included 27 women with a history of successful pregnancies and no miscarriage. We determined IL-6 and TNF-alpha production in peripheral blood cultured with LPS, as well as IFN-gamma and TGF-beta induced by PHA stimulation. Cytokines were measured by enzyme-linked immunoabsorbant assay (ELISA) using commercial kits (RD, Amersham-Pharmacia). Mann-Whitney test was applied to compare differences between groups. The level of significance was defined at P < 0.05. We observed significantly higher levels of IFN-gamma (355.8 pg/ml versus 98.0 pg/ml; P = 0.01) and a trend toward increased TNF-alpha production (2410.2 pg/ml versus1980.2 pg/ml; P = 0.07) in RPL women as compared to controls. In relation to IL-6 and TGF-beta, no significant difference was detected between RPL and control groups. In agreement with experimental observations, our data support the hypothesis of Th1 cytokine involvement in the pathogenesis of RPL.

Lack of association of TNFα gene polymorphisms and recurrent pregnancy loss in Caucasian women

The tumor necrosis factor alpha (TNFalpha) gene plays an important role in immunology and inflammation. Variant alleles of TNFalpha are associated with altered RNA and serum protein levels in humans. Conflicting results have been obtained regarding the role of TNFalpha during pregnancy and recurrent pregnancy loss (RPL). This study investigated the relationship between RPL and two polymorphisms in the promoter of the TNFalpha gene (TNFalpha -308 and -863). Genotyping was performed in 168 RPL women and 212 ethnically matched healthy individuals. In addition, we performed analysis of TNFalpha serum protein levels. We demonstrate that neither the polymorphism -308 nor the polymorphism -863 of the TNFalpha gene is associated with RPL in Caucasian women. In addition, we did not find any association between TNFalpha serum levels and the occurrence of RPL in a subset of 36 RPL women and 36 healthy individuals. We conclude that TNFalpha polymorphisms and resting blood TNFalpha levels do not correlate with the propensity to recurrent pregnancy loss in Caucasian women.

Safety of Tumour Necrosis Factor-?? Antagonists

Tumour necrosis factor-alpha (TNFalpha) is a proinflammatory cytokine that is synthesised by a variety of cell types in response to infectious or inflammatory stimuli. Although TNFalpha plays an adaptive role in immune protection and wound healing at 'physiological' levels, excess TNFalpha production can lead to adverse consequences. TNFalpha is a pivotal cytokine involved in the pathogenesis and progression of rheumatoid arthritis (RA). TNFalpha antagonists have been shown to be effective in the treatment of signs and symptoms of RA and the US FDA has approved three TNFalpha antagonists, etanercept, infliximab, and most recently, adalimumab, for the treatment of RA. However, differences have emerged, with respect to their demonstrated efficacy in other diseases (e.g. Crohn's disease). Worldwide, over half a million patients have been treated with TNFalpha antagonists and concerns regarding their safety have been raised. There is a risk of reactivation of granulomatous diseases, especially tuberculosis, with all three agents and appropriate measures should be taken for detection and treatment of latent infections. An association between non-Hodgkin's lymphoma and treatment with TNFalpha antagonists has been reported, although patients with active, long-standing RA are already known to have an increased incidence of non-Hodgkin's lymphoma. No associations with solid tumours have been found to date. The biological plausibility of lymphomas associated with immunomodulatory agents raises concern and vigilance is appropriate until the relationship is fully characterised. Large phase II and III trials have shown a detrimental effect of TNFalpha antagonists in advanced heart failure and these agents should be avoided in this population. Rare case reports of drug-induced lupus, seizure disorder, pancytopenia and demyelinating diseases have been noted after TNFalpha antagonists and continued vigilance is warranted in patients on TNFalpha antagonists for the development of these diseases. At present there is no evidence implicating TNFalpha antagonists with embryotoxicity, teratogenicity or increased pregnancy loss.

Role of tumour necrosis factor-alpha in insulin resistance during normal pregnancy

OBJECTIVE

Role of tumour necrosis factor-alpha (TNF-alpha) was studied in insulin resistance during pregnancy.

STUDY DESIGN

Serum TNF-alpha (ELISA) and fasting C-peptide (Cp) (RIA) concentrations were measured in 40 healthy pregnant women (15, 12 and 13 of them in the 1st, 2nd and 3rd trimesters, respectively) and in 25 healthy non-pregnant women in a case-control study.

RESULTS

TNF-alpha (X+/-S.D.: 5.33+/-0.46 pg/ml) and Cp levels (3.37+/-1.30 ng/ml) were significantly higher in the 3rd trimester as compared with matched healthy controls (TNF: 4.07+/-0.26, Cp: 1.05+/-0.36) and to the pregnant women in 1st (TNF: 4.04+/-0.26, Cp: 1.34+/-0.59) and 2nd (TNF: 4.35+/-0.32, Cp: 1.11+/-0.35) trimesters. Significant positive linear correlation was calculated among TNF-alpha, Cp, Cp/blood glucose ratio (indirect parameters of insulin resistance) and body mass indexes (BMIs) of pregnant women (P<0.01).

CONCLUSION

TNF-alpha may contribute to the insulin resistance during the course of normal pregnancy.

Associations between cytokine gene polymorphisms and recurrent pregnancy loss

Since certain cytokines may play a role in unexplained recurrent pregnancy loss (RPL) and also some cytokine gene polymorphisms may affect the level of cytokine production, the aim of the present study was to investigate the relationship between RPL and polymorphisms of the genes coding for TNF-alpha (-308 G-->A), IL-10 (-1082 G-->A), IL-6 (-174 G-->C), and IFN-gamma (+874 A-->T). Genotyping was performed in 48 RPL women and 108 ethnically matched healthy individuals. In addition, we performed a meta-analysis encompassing the present results and those from studies on the association of TNF-alpha, IL-10 and IFN-gamma polymorphisms with RPL published in the literature until December 2001. The results showed: (1) no evidence of association with IL-6 gene polymorphisms; (2) significant associations, revealed by the meta-analysis, with the high cytokine production genotypes of IFN-gamma (+874 T/T: odds ratio (OR)=1.92, P=0.04) and IL-10 (-1082 G/G: OR=1.75, P=0.03), and a trend for association with the high TNF-alpha production genotypes -308 A/A and A/G (OR=1.61; P=0.18). We believe that the associations of these genotypes with RPL are interesting not only as risk factors but also because they represent another piece of evidence that these cytokines might be important in the pathogenesis of RPL.

Brief review: hypertension in pregnancy : a manifestation of the insulin resistance syndrome?

Pregnancy-induced hypertension (PIH), which includes both gestational hypertension and preeclampsia, is a common and morbid pregnancy complication for which the pathogenesis remains unclear. Emerging evidence suggests that insulin resistance, which has been linked to essential hypertension, may play a role in PIH. Conditions associated with increased insulin resistance, including gestational diabetes, polycystic ovary syndrome, and obesity, may predispose to hypertensive pregnancy. Furthermore, metabolic abnormalities linked to the insulin resistance syndrome are also observed in women with PIH to a greater degree than in normotensive pregnant women: These include glucose intolerance, hyperinsulinemia, hyperlipidemia, and high levels of plasminogen activator inhibitor-1, leptin, and tumor necrosis factor-alpha. These observations suggest the possibility that insulin resistance may be involved in the pathogenesis of PIH and that approaches that improve insulin sensitivity might have benefit in the prevention or treatment of this syndrome, although this requires further study.