Risk Of Gestational Hypertension Research Articles

Sympathovagal Imbalance, Decreased Baroreflex Sensitivity and Increased Myocardial Work Stress in Pregnant Women with Risk of Developing Gestational Hypertension: A Preliminary Report

Background and Aim: Though the mechanisms responsible for the pathogenesis of Gestational Hypertension (GHT) are unclear, it has been reported that the disease is characterized by low circulating volume and high vascular resistance. The increased peripheral vascular resistance is caused due to sympathetic overactivity which in turn causes the increase in blood pressure and Cardiovascular risk (CV). Therefore, in the present study, we aimed to study the sympathovagal imbalance, Baroreflex Sensitivity (BRS) and Rate Pressured Product (RPP) in pregnant women with risk of developing GHT during their first and third trimesters of gestation. Methods: Heart Rate (HR), Systolic and Diastolic Blood Pressure (SBP, DBP) were measured. Rate-pressure product was calculated using SBP and HR. Spectral analysis of Heart Rate Variability (HRV), Blood Pressure Variability (BPV) including BRS were assessed in a group of pregnant women (n=18) with risk factors for GHT at 16th week and 36th week of their gestation. Parameters were compared after 36th week with 16th weeks and analyzed. Results: It was observed that the ratio of low-frequency to high-frequency power (LF-HF ratio) of HRV was significantly increased at 36th week of pregnancy compared with 16th week. There was decreased BRS at 36th week of pregnancy in risk of GHT. Significant increase in RPP was seen at 36th week of pregnant women with risk of developing GHT when compared with 16th of gestation. Conclusion: In the present study we conclude that there is sympathovagal imbalance in pregnant women with risk of developing GHT. Also reduced BRS and increased RPP were seen in these subjects indicating that there was increased CV risk in these patients.

NR3C2 gene polymorphism is associated with risk of gestational hypertension in Han Chinese women.

Background:The influence of genetic polymorphisms on the development of gestational hypertension (GH) is unclear. The aim of this study was to examine whether single-nucleotide polymorphisms (SNPs) of the nuclear receptor subfamily 3, group C, member 2 (NR3C2) genes, rs5522, rs2070951, rs5534, s2248038, and s9992256 are associated with GH in Han Chinese women.Method:Sanger sequencing was used to analyze the genotypes of rs5522, rs2070951, rs5534, rs2248038, and rs9992256 loci of the NR3C2 gene in 450 patients with GH and 450 healthy controls.Results:The rs5522 dominant model (odds ratio [OR] = 1.30, 95% confidence interval [CI]: 1.13–1.47, P < .001) and the recessive model (OR = 1.64, 95% CI: 1.33–1.86, P < .001) had higher GH risk. The rs2070951 dominant model (OR = 1.18, 95% CI: 1.03–1.35, P = .02) had higher risk of GH, and the recessive model (OR = 1.09, 95% CI: 0.84–1.34, P = .55) was not significant for GH risk. The rs5534 dominant model (OR = 1.25, 95% CI: 1.09–1.43, P = .001) had a higher GH risk. The rs2248038 and rs9992256 sites were not significantly related to GH risk. Gene–gene interactions at the rs5522, rs2070951, and rs5534 loci affected GH risk (OR = 1.34, 95% CI: 1.12–1.64, P < .001).Conclusion:The SNPs of the NR3C2 gene rs5522, rs2070951, and rs5534 are associated with GH in Han Chinese women.

Prevalence and risk of pre-eclampsia and gestational hypertension in twin pregnancies: a population-based register study

ObjectivesThe aim of this study was to assess the prevalence and risk of pre-eclampsia and gestational hypertension in twin pregnancies compared with singleton pregnancies.DesignPopulation-based cohort study.SettingMedical Birth Registry of Norway...

Use of antidepressants and anxiolytics in early pregnancy and the risk of preeclampsia and gestational hypertension: a prospective study

BackgroundWe investigated the association between antidepressant and anxiolytic exposure during the first and early second trimester of pregnancy (< 16 weeks), and hypertensive disorders of pregnancy (including preeclampsia and gestational hypertension) in women with singleton pregnancy.MethodsThis study is based on a large prospective cohort of 7866 pregnant women. We included pregnant women aged 18 years or older without chronic hepatic or renal disease at the time of recruitment. Participants lost to the follow-up, with multiple pregnancies and pregnancy terminations, miscarriages or fetal deaths before 20 weeks of gestation were excluded from the study, as well as women with no data on the antidepressant/anxiolytic medication use during pregnancy. Information concerning antidepressant or anxiolytic medication use was extracted from hospital records after delivery. The associations between their use and the risk of gestational hypertension or preeclampsia were calculated.ResultsThe final sample for analysis included 6761 participants including 218 (3.2%) women who were exposed to antidepressant and/or anxiolytic medication before the 16th week of gestation. Forty-one women had a non-medicated depression or anxiety during the pregnancy. Moreover, 195 (2.9%) and 122 (1.8%) women developed gestational hypertension and preeclampsia respectively. When compared to women unexposed to antidepressant/anxiolytic medication, depression and anxiety, those using antidepressant and/or anxiolytic drugs before the 16th week of gestation were at increased risk of preeclampsia (adjusted odd ratio (aOR) 3.09 [CI95% 1.56–6.12]), especially if they continued their medication after the 16th week (aOR 3.41 [CI95% 1.66–7.02]) compared to those who did not (1.60 [CI95% 0.21–12.34]).ConclusionsWomen exposed to antidepressant and/or anxiolytic medication before the 16th week of pregnancy have a 3-fold increased risk for preeclampsia when compared to women unexposed to antidepressant/anxiolytic medication, depression and anxiety. Also, our results suggested that women who stopped their medication before the 16th week of pregnancy could be benefit from reduced preeclampsia risk.

Genetic variants in DICER1, DROSHA, RAN, and XPO5 genes and risk of pregnancy-induced hypertension.

To evaluate the impact of microRNA (miRNA) machinery gene polymorphisms on the risk of gestational hypertension (GH) and preeclampsia (PE). A case-control study among Han Chinese with a total of 143 patients diagnosed with PE, 79 with GH, and 330 healthy controls was conducted. Nine candidate SNPs in 4 selected miRNA biogenesis genes were genotyped, including three DICER1 SNPs (rs3742330, rs1057035 and rs13078), two DROSHA SNPs (rs17409893 and rs642321), two RAN SNPs (rs3803012 and rs14035), and two XPO5 SNPs (rs1106841 and rs2257082). Logistic regression was used to estimate the odds ratios (OR) and 95% confidence intervals (CIs) for the associations. The DICER1 rs13078 TA genotype was still strongly associated with an increased risk of GH (OR = 3.17 (95% CI: 1.55, 6.48)), and the RAN rs3803012 AG genotype was associated with an increased risk of PE (OR = 2.15 (1.26, 3.66)). The RAN rs14035/rs3803012 haplotype C-G was associated with PE susceptibility (OR = 2.08 (95% CI: 1.19, 3.62)); however, the haplotype C-A was a protective factor for PE (OR = 0.68 (95% CI: 0.50, 0.93)). The DICER1 rs1057035/ rs13078/ rs3742330 haplotype T-A-A and DORSHA rs17409893/rs642321 haplotype A-T were both associated with increased risk of GH (OR = 2.75 (95% CI:1.40, 5.38) and OR = 1.60 (95% CI:1.12, 2.29), respectively). These significant associations were retained after false-positive discovery rate correction (p < 0.05). Genetic variants in miRNA machinery genes might participate in the development of pregnancy-induced hypertension. The DICER1 rs1078 polymorphism is associated with GH and the RAN rs3803012 polymorphism is associated with PE.

Prenatal exposure to perfluoroalkyl and polyfluoroalkyl substances and the risk of hypertensive disorders of pregnancy

BackgroundPerfluoroalkyl and polyfluoroalkyl substances (PFAS) have been reported to disrupt endocrine system and reproduction. However, epidemiological evidence on the association between PFAS and preeclampsia is inconsistent. We aimed to investigate the association between prenatal PFAS exposure and hypertensive disorders of pregnancy (HDP) in humans.MethodsPFAS were measured by liquid chromatography system coupled with tandem mass spectrometry in 687 umbilical cord plasma samples collected between 2011 and 2012 in Shanghai, China. Information on HDP including gestational hypertension and preeclampsia was abstracted from medical records. Multiple logistic regression was used to examine the association of each PFAS with gestational hypertension, preeclampsia, and overall HDP in separate models. Elastic net regression with logit link was used to identify independent associations between exposures and outcomes. Logistic regression was used to obtain the unpenalized estimates of the selected PFAS components for the associations with outcomes, adjusting for age, education level, pre-pregnancy BMI, parity, and mutual adjustment of selected PFAS.ResultsThe risk of gestational hypertension and preeclampsia was 3.3% and 2.8% in our subjects, respectively. Perfluorobutane sulfonate (PFBS), perfluorohexane sulfonate (PFHxS), perfluoroundecanoic acid (PFUA) were associated with preeclampsia based on elastic net penalty regression. In the fully adjusted statistical model, women with a higher level of standardized ln-transformed PFBS had an increased odds of preeclampsia [adjusted odds ratio (AOR): 1.81, 95% confidence interval (CI): 1.03–3.17], and overall HDP (AOR: 1.64, 95% CI: 1.09–2.47).ConclusionsPrenatal exposure to PFBS was positively associated with the risk of preeclampsia and overall HDP.

Effects of Aerobic Exercise on Blood Pressure during Pregnancy: A Case Study

BACKGROUND: Gestational hypertension is one of the leading causes of maternal morbidity and mortality.(1). Pregnancy induced hypertension is defined as systolic blood pressure >140mmhg and diastolic blood pressure >90mmhg. Mild PIH is defined as SBP 140-149mmhg and DBP 90-99mmhg(3) Hypertensive disorders may result in fetal complication, such as growth restriction, oligohydramnios, placental abruption, preterm birth and preinatal death(1 )(1,2) The prevalence of all pregnancies with some form of hypertension can be up to 10%, with the rates of diagnosis varying according to the country and population studied and the criteria used to establish the diagnosis.(3). Gestational hypertension is associated with short and long term issues for mother and child. The aim of the study was to evaluate the effects of exercise during pregnancy on the risk of gestational hypertensive disorders. CASE REPORT: A 28 years primi pregnant women came with complain loss of established BP control, symptoms/signs such as headache, blurred vision, right upper quadrant or epigastric pain, and diagnosed to have gestational hypertension (SBP 140 mmhg and DBP 90 mmhg) with gestational age of 22weeks. CONCLUSION: Aerobic exercise for about 30- 60 mins two to seven times per week during pregnancy as compared with being more sedentary is associated with a significantly reduced risk of gestational hypertensive disorder, gestational hypertension and cesarean delivery(1).

Exploring the concept of functional vitamin D deficiency in pregnancy: impact of the interaction between 25-hydroxyvitamin D and parathyroid hormone on perinatal outcomes

Associations of vitamin D with perinatal outcomes are inconsistent and few studies have considered the wider calcium metabolic system. We aimed to explore functional vitamin D deficiency in pregnancy by investigating associations between vitamin D status, parathyroid hormone (PTH), and perinatal outcomes. SCOPE (Screening for Pregnancy Endpoints) Ireland is a prospective cohort study of low-risk, nulliparous pregnant women. We measured serum 25-hydroxyvitamin D [25(OH)D] and PTH at 15 wk of gestation in 1754 participants. Mean±SD 25(OH)D was 56.6±25.8 nmol/L (22.7±10.3ng/mL) and geometric mean (95% CI) PTH was 7.84 pg/mL (7.7, 8.0 pg/mL) [0.86 pmol/L (0.85, 0.88 pmol/L)]. PTH was elevated in 34.3% of women who had 25(OH)D <30nmol/L and in 13.9% of those with 25(OH)D ≥75 nmol/L. Whereas 17% had 25(OH)D <30 nmol/L, 5.5% had functional vitamin D deficiency, defined as 25(OH)D <30 nmol/L with elevated PTH. Elevated mean arterial pressure (MAP), gestational hypertension, pre-eclampsia, and small-for-gestational-age (SGA) birth were confirmed in 9.2%, 11.9%, 3.8%, and 10.6% of participants, respectively. In fully adjusted regression models, neither low 25(OH)D nor elevated PTH alone increased the risk of any individual outcome. The prevalence of elevated MAP (19.1% compared with 9.7%) and SGA (16.0% compared with 6.7%) were highest (P<0.05) in those with functional vitamin D deficiency compared with the reference group [25(OH)D ≥75 nmol/L and normal PTH]. The adjusted prevalence ratio (PR) and RR (95% CIs) for elevated MAP and SGA were 1.83 (1.02, 3.27) and 1.53 (0.80, 2.93), respectively. There was no effect of functional vitamin D deficiency on the risk of gestational hypertension (adjusted RR: 1.00; 95% CI: 0.60, 1.67) or pre-eclampsia (adjusted RR: 1.17; 95% CI: 0.32, 4.20). The concept of functional vitamin D deficiency, reflecting calcium metabolic stress, should be considered in studies of vitamin D in pregnancy. The SCOPE pregnancy cohort is registered at http://www.anzctr.org.au as ACTRN12607000551493.

Dental Amalgams and Risk of Gestational Hypertension in the MIREC Study

Dental Amalgams and Risk of Gestational Hypertension in the MIREC Study

Parental Age and the Risk of Gestational Hypertension and Preeclampsia

To determine the effect of maternal age (MA) and paternal age (PA) on the risk of gestational hypertension, preeclampsia, and eclampsia in women who delivered on the Texas-Mexico border. A cohort study using birth certificate data (singleton pregnancies, years 2005-2010) from El Paso County, Texas, was conducted. Six parental age-exposure categories were created with MA 20 to 34 years and PA younger than 35 years serving as the referent. A directed acyclic graph was created. Adjusted risk ratios for the composite outcome of gestational hypertension, preeclampsia, or eclampsia were calculated using Poisson regression. A total of 85,114 records were identified, with a majority of the mothers being of Hispanic ethnicity (89.2%). The incidence of the composite outcome ranged from 2.8% in the MA 20 to 34 years old and PA 35 years and older group to 4.4% in the MA younger than 20 years old and PA 35 years and older group. Compared to the MA 20 to 34 years old and PA younger than 35 years group, women in the MA 35 years and older and PA 35 years and older groups were more likely to experience the outcome (adjusted risk ratio 1.57, 95% confidence interval 1.39-1.77, P < 0.0001). Couples in which both parents are 35 years old and older should be counseled on the increased risk of gestational hypertension or preeclampsia/eclampsia.

Supplementation of folic acid in pregnancy and the risk of preeclampsia and gestational hypertension: a meta-analysis

ObjectivesWe aimed to systematically assess the relationship between folic acid supplementation in pregnancy and risk of preeclampsia and gestational hypertension.MethodsThe relevant studies were included by retrieving the Embase, PubMed and Cochrane library databases. Data extraction was conducted by two investigators independently. The risk ratio (RR) and 95% confidence interval (CI) were used as effect indexes to evaluate the relationship between folic acid supplementation and risk of gestational hypertension or preeclampsia. A subgroup analysis was performed according to the supplementation patterns of folic acid. The homogeneity of the effect size was tested across the studies, and publication biases were examined.ResultsIn total, 13 cohort studies and 1 randomized controlled trial study was included, containing 160,562 and 149,320 women with and without folic acid supplementation during pregnancy. Pooled results showed that risk of gestational hypertension was not associated with the supplementation of folic acid. However, folic acid supplementation during pregnancy could significantly reduce the risk of preeclampsia. Moreover, the results of subgroup analysis showed that the decreased preeclampsia risk was associated with supplementation of multivitamins containing folic acid rather than folic acid alone.ConclusionsOur findings indicate that the supplementation of multivitamins containing folic acid during pregnancy could significantly lower preeclampsia risk.

Vitamin D and risk of pregnancy related hypertensive disorders: mendelian randomisation study

ObjectiveTo use mendelian randomisation to investigate whether 25-hydroxyvitamin D concentration has a causal effect on gestational hypertension or pre-eclampsia.DesignOne and two sample mendelian randomisation analyses.SettingTwo European pregnancy cohorts (Avon Longitudinal...

Antidepressant use during pregnancy and the risk of developing gestational hypertension: a retrospective cohort study

BackgroundPrior studies reported that exposure to antidepressants during pregnancy may be associated with gestational hypertension. The aim of this study is to assess the association between the use of antidepressants during pregnancy and the risk of developing gestational hypertension.MethodsA retrospective cohort study using the prescription database IADB.nl was conducted among nulliparous women with singleton pregnancies between 1994 and 2015 in the Netherlands. Logistic regression analysis was used to estimate odds ratios (OR), adjusted OR (aOR) and their corresponding 95% confidence intervals (95% CI). Gestational hypertension as main outcome measure was defined as at least one dispensed record of an antihypertensive drug (methyldopa, nifedipine, labetalol, ketanserin, nicardipine) after 20 weeks of gestation until 14 days after delivery. Sub-analyses were conducted for class of antidepressant, duration and amount of use of antidepressant (≤30, ≥30 Defined Daily Doses or DDDs), and maternal age. Sensitivity analyses to assess uncertainties were conducted.ResultsTwenty-eight thousand twenty women were included, of which 539 (1.92%) used antidepressants. The risk of gestational hypertension was doubled for women using antidepressant (aOR 2.00 95% CI 1.28–3.13). Significant associations were also found for the subgroup selective serotonin reuptake inhibitors (SSRIs) (aOR 2.07 95% CI 1.25–3.44), ≥30 DDDs (aOR 2.50 95% CI 1.55–3.99) and maternal age of 30–34 years (aOR 2.59 95% CI 1.35–4.98). Varying the theoretical gestational age showed comparable results.ConclusionProlonged use of antidepressants during the first 20 weeks of gestation appeared to be associated with an increased risk of developing gestational hypertension. When balancing the benefits and risks of using these drugs during pregnancy, this should be taken into account.

The Effect of Maternal Obesity on Maternal and Neonatal outcome in Pregnant Saudi Females

Background: Obese women are at an increased risk of various adverse pregnancy outcomes. The aim of our study was to evaluate the impact of obesity on maternal and neonatal outcomes in Saudi Pregnant Females and to compare obstetric outcomes by the level of maternal obesity. Materials and Methods: A Retrospective cohort study included 2517 women with singleton gestations who gave birth at the Department of Obstetrics and Gynecology, Security Forces Hospital, Riyadh, Sauid Arabia in 2016. Pregnancy complications and neonatal outcomes were identified using the hospital Medical Record Viewer Database. Women were divided into two groups based on their BMI in their first antenatal visit into, non-obese with BMI <30 kg/m2 and obese with BMI ≥ 30 kg/m2. Furthermore obese women were subcategorized into two groups (BMI 30- 34.9 kg/m2, and BMI ≥ 35 kg/ m2, ) and pregnancy outcomes were compared between these and non-obese pregnant women. Results: Obese women were significantly more likely to have gestational hypertension (OR=8.59; 95% CI, 5.23-14.14; P<0.0001), preeclampsia (OR=2.06; 95% CI, 1.14-3.73; P<0.0001), gestational diabetes (OR=5.56; 95% CI, 3.66-8.49; P<0.0001), dystocia (OR=2.14; 95% CI, 1.36-3.38; P<0.0001), induced labor (OR=2.64; 95% CI, 1.83-3.80; P<0.0001), failed induction of labor (OR=18.06; 95% CI, 8.85-36.84; P<0.0001), cesarean delivery (OR=1.76; 95% CI, 1.25-2.49; P=0.001), large-for-gestational-age newborns (OR=3.68; 95% CI, 2.51 5.39; P<0.0001). Significantly increased risk of gestational diabetes, preeclampsia, dystocia and newborns with Apgar score ≤ 7 after 5 min was only observed in women with BMI ≥ 35 kg/m2. Conclusions: Maternal obesity is significantly associated with an increased risk of gestational hypertension, preeclampsia, gestational diabetes, dystocia, labor induction, failed induction of labor, large-for-gestational-age newborns and cesarean delivery.

Correlation of Maternal Serum Homocysteine in the First Trimester with the Development of Gestational Hypertension and Preeclampsia.

BackgroundThis study investigated the relationship of serum homocysteine in early pregnancy with the risk of gestational hypertension (GH) and preeclampsia (PE) and with the severity of preeclampsia.Material/MethodsIn a retrospective cohort study, we identified 147 confirmed cases of preeclampsia (103 with mild PE and 44 with severe PE) and 147 confirmed cases of GH; 4418 women who remained normotensive and nonproteinuric throughout pregnancy served as controls. Maternal blood samples were collected at between 11 and 13 weeks of gestation to test serum concentrations of homocysteine (Hcy), folic acid, and VitB12. A logistic regression model was used to calculate adjusted odds ratios (aORs) and 95% confidence intervals (CIs).ResultsWomen who subsequently developed GH and PE were older and had higher body mass indexes (BMIs) than those in the control group. Compared with the control group, women who developed PE were less educated (P=0.031), and more of those who developed GH were primiparas (P=0.012). The serum levels of Hcy in severe PE were significantly higher than those in the control group (median: 8.50 μmol/L vs. 7.33 μmol/L, P<0.001). After logistic regression analyses for potential confounding factors, the adjusted odds ratios (aORs) of Hcy was 1.12 for severe PE (95% CI 1.06–1.20). The serum concentrations of folic acid and VitB12 in those with GH and PE were not significantly different from controls.ConclusionsA high level of Hcy in the first trimester is an independent risk factor for severe PE, although it is not a useful marker for the subsequent development of GH and mild PE.

2009 IOM guidelines for gestational weight gain: how well do they predict outcomes across ethnic groups?

ABSTRACTObjective: To determine whether the Institute Of Medicine's (IOM) 2009 guidelines for weight-gain during pregnancy are predictive of maternal and infant outcomes in ethnic minority populations.Methods: We designed a population-based study using administrative data on 181,948 women who delivered live singleton births in Washington State between 2006–2008. We examined risks of gestational hypertension, preeclampsia/eclampsia, cesarean delivery, and extended hospital stay in White, Black, Native-American, East-Asian, Hispanic, South-Asian and Hawaiian/Pacific islander women according to whether they gained more or less weight during pregnancy than recommended by IOM guidelines. We also examined risks of neonatal outcomes including Apgar score <7 at 5 min, admission to NICU, requirement for ventilation, and a diagnosis of small or large for gestational age at birth.Results: Gaining too much weight was associated with increased odds for gestational hypertension (adjusted OR (aOR) ranged between 1.53–2.22), preeclampsia/eclampsia (aOR 1.44–1.81), cesarean delivery (aOR 1.07–1.38) and extended hospital stay (aOR 1.06–1.28) in all ethnic groups. Gaining too little weight was associated with decreased odds for gestational hypertension and delivery by cesarean section in Whites, Blacks and Hispanics. Gaining less weight or more weight than recommended was associated with increased odds for small for gestational age and large for gestational age infants respectively, in all ethnic groups.Conclusions: Adherence to the 2009 IOM guidelines for weight gain during pregnancy reduces risk for various adverse maternal outcomes in all ethnic groups studied. However, the guidelines were less predictive of infant outcomes with the exception of small and large for gestational age.Abbreviations: GWG: Gestational weight gain; IOM/NRC; Institute of Medicine and National Research Council; NICU: Neonatal intensive care need for ventilation; SGA: Small for gestational age; LGA: Large for gestational age; BERD: Birth Events Records Database; CHARS: Comprehensive Hospital Discharge Reporting System; ICD: International Classification of Disease; LMP: Last menstrual period; OR: Odds ratio

The impact of salt intake during and after pregnancy.

Although high blood pressure before pregnancy is associated with a risk of gestational hypertension and preeclampsia, no convincing evidence has been produced to show that dietary salt reduction helps in the prevention and treatment of hypertension during pregnancy. Thus the current guidelines do not recommend a sodium restriction during pregnancy to prevent gestational hypertension and the development of preeclampsia. However, the long-term impact of hypertensive disorders of pregnancy for life-threatening diseases later in life is a critical issue. Gestational hypertension could contribute to the risk of developing hypertension later in life, and recent studies have suggested that gestational hypertension and preeclampsia are linked to cardiovascular complications. In this article, we provide an overview of the current perspectives on the salt intake of pregnant women and consider both the short-term influence and the impact beyond the perinatal period.

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

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

Ambient Air Pollution and Risk of Gestational Hypertension.

Air pollution has been linked to hypertension in the general population, but data on gestational hypertension (GH) are limited. We investigated criteria air pollutants and air toxics during the period before conception and in early gestation in relation to GH risk in the Consortium on Safe Labor/Air Quality and Reproductive Health Study (United States, 2002-2008). Modified Community Multi-scale Air Quality models estimated air pollution exposures for 6,074 singleton pregnancies in which GH was present and 199,980 normotensive pregnancies. Generalized estimating equations estimated relative risks per interquartile-range increment for pollutants and high exposure (≥75th percentile) for air toxics after adjustment for major risk factors. For an interquartile-range increment, GH risk was significantly increased by 18% for sulfur dioxide during the 3 months before conception and, during gestational weeks 1-20, 17% for nitrogen oxides, 10% for particulate matter with an aerodynamic diameter <2.5 μm, 7% for particulate matter with an aerodynamic diameter <10 μm, and 22% for sulfur dioxide. High exposures to several polycyclic aromatic hydrocarbons before conception and during the first trimester were significantly associated with 8%-20% higher risk of GH. Further, preconceptional exposures to several volatile organic compounds were significantly associated with 11%-19% higher risk. Our findings suggest that early exposures to criteria air pollutants, particularly from transport emissions, and high exposure to several air toxics before conception may increase GH risk.

Dietary supplements and drugs for preeclampsia prophylaxis

Pre-eclampsia (PE) is a major cause of mortality and morbidity during pregnancy. Many different strategies to prevent PE have been investigated in randomized controlled trials, but none have been found to be widely effective and this is not surprising given the complexities in pathogenesis. Low-dose aspirin, diminishing platelet thromboxane synthesis, seems to prevent or delay PE. A meta-analysis of individual patient data from 32,217 women (PARIS collaborative group) asses that low-dose aspirin during pregnancy is associated with moderate reduction in the relative risk of PE (RR 0.90 95%CI 0.84–0.97), of birth before 34 weeks’ gestation (RR 0.90 95%CI 0.83–0.98), and of having a pregnancy with a serious adverse outcome (RR 0.90 95%CI 0.85–0.96). This effect seems to be more significant in women at high risk of developing PE. Regarding diet and nutrients, there does not appear to be any clear benefit for prevention of PE from routine dietary supplementation. There is high quality evidence that vitamin C and vitamin E are not effective for prevention or treatment of PE. Actually a meta-analyses found that supplementation with these antioxidants is associated with a slightly increased risk of gestational hypertension and premature rupture of membranes. Also there is not enough high-quality evidence to show that dietary magnesium or omega-3 fatty acids supplementation during pregnancy is beneficial. Calcium supplementation instead appears to reduce the risk of PE and the rare occurrence of the composite outcome ’death or serious morbidity’ specially in women with a low baseline calcium intake. Some studies assess that preeclamptic women may be deficient in nitric oxide, which mediates vasodilatation and inhibits platelet aggregation. For this reason NO donors, such as isosorbide dinitrate, glyceryl trinitrate and S-Nitroglutathione, were used in some trials as treatment in preeclamptic women. Despite the reduction in blood pressure and in uterine artery pulsatility index, these substances were rarely used in clinical practice because of adverse effects such as headache or preoxynitrite production. Also l -arginine, the substrate for synthesis of nitric oxide, has been investigated as a mean of preventing PE. Even though a dysfunction of the l -arginine-NO pathway that seems to be present in preeclamptic women, l -arginine load appears to be associated with increased nitric oxide (NO) production, hypotension and reduction of PE/eclampsia rate. Also in obese women there is a dysfunction of the l -arginine-NO pathway that causes a decrease of endothelial-dependent vasodilatation. In these women a l -arginine supplement could be helpful. Conclusion Aspirin proven to be of some help provided dose and timing are adequate. Impact on PE is limited, and its use is better in high-risk. Calcium supply could be helpful in population with low dietary intake. l -Arginine supplementation is worth to receive the same attention aspirin had also considering that biological activity seems wider. Actual evidences are more robust than the ones that allows wasting time and money for Vitamins C and E.