Does race or ethnicity play a role in the origin, pathophysiology, and outcomes of preeclampsia? An expert review of the literature

Genetic variation in placental insufficiency: What have we learned over time?

Genetic variation shapes placental development and function, which has long been known to impact fetal growth and pregnancy outcomes such as miscarriage or maternal pre-eclampsia. Early epidemiology studies provided evidence of a strong heritable component to these conditions with both maternal and fetal-placental genetic factors contributing. Subsequently, cytogenetic studies of the placenta and the advent of prenatal diagnosis to detect chromosomal abnormalities provided direct evidence of the importance of spontaneously arising genetic variation in the placenta, such as trisomy and uniparental disomy, drawing inferences that remain relevant to this day. Candidate gene approaches highlighted the role of genetic variation in genes influencing immune interactions at the maternal-fetal interface and angiogenic factors. More recently, the emergence of molecular techniques and in particular high-throughput technologies such as Single-Nucleotide Polymorphism (SNP) arrays, has facilitated the discovery of copy number variation and study of SNP associations with conditions related to placental insufficiency. This review integrates past and more recent knowledge to provide important insights into the role of placental function on fetal and perinatal health, as well as into the mechanisms leading to genetic variation during development.

Immediate weight loss before ovarian stimulation with intrauterine insemination is associated with a lower risk of preeclampsia in women with obesity and unexplained infertility

Objective

To determine whether successful weight loss before ovarian stimulation with intrauterine insemination (OS-IUI) affects the risk of future pregnancy complications among women with obesity and unexplained infertility after fertility treatment.

Design

Secondary analysis of the randomized controlled clinical trial Improving Reproductive Fitness Through Pretreatment With Lifestyle Modification in Obese Women With Unexplained Infertility (FIT-PLESE).

Setting

Multiple academic health centers in the United States.

Patient(s)

Three hundred seventy-nine women with obesity and unexplained infertility who underwent standard infertility treatment after a lifestyle intervention.

Intervention(s)

The FIT-PLESE trial evaluated whether prepregnancy lifestyle interventions (diet with weight loss medication and exercise vs. exercise alone) before OS-IUI improved the live birth rate among women with obesity and unexplained infertility. Although the primary outcome of FIT-PLESE was live birth rate, we compared the demographics and subsequent pregnancy complications of women who successfully lost some weight with those of women who did not lose any during the interventions.

Main Outcome Measure(s)

Obstetric complications by groups were compared using χ² and Fisher’s exact tests, and continuous variables were compared using Student’s t-tests. Logistic regression was used to assess the odds of preeclampsia after adjustment for the randomized treatment arm in FIT-PLESE.

Result(s)

There was a nonsignificant trend toward a lower risk of intrauterine growth restriction (4% vs. 16%, P = .124) and preterm delivery (6% vs. 15%, P = .343) among patients who lost at least some weight. The risk of preeclampsia was significantly lower (6% vs.35%, P = .002) in the weight loss group (odds ratio, 0.09; 95% confidence interval, 0.016–0.505; P = .006) after adjustment for treatment assignment.

Conclusion(s)

Among women with obesity and unexplained infertility who had live births after fertility treatment, prepregnancy weight loss due to lifestyle interventions before OS-IUI was associated with a lower risk of preeclampsia.

Hypertensive Disorders of Pregnancy and Cardiovascular Disease Risk Across Races and Ethnicities: A Review

Pregnancy is often considered to be a "cardiometabolic stress-test" and pregnancy complications including hypertensive disorders of pregnancy can be the first indicator of increased risk of future cardiovascular disease. Over the last two decades, more evidence on the association between hypertensive disorders of pregnancy and cardiovascular disease has become available. However, despite the importance of addressing existing racial and ethnic differences in the incidence of cardiovascular disease, most research on the role of hypertensive disorders of pregnancy is conducted in white majority populations. The fragmented knowledge prohibits evidence-based targeted prevention and intervention strategies in multi-ethnic populations and maintains the gap in health outcomes. In this review, we present an overview of the evidence on racial and ethnic differences in the occurrence of hypertensive disorders of pregnancy, as well as evidence on the association of hypertensive disorders of pregnancy with cardiovascular risk factors and cardiovascular disease across different non-White populations, aiming to advance equity in medicine.

Nonadherence to treatment protocol for severe hypertension in pregnancy

BACKGROUND

Hypertensive disorders of pregnancy are one of the leading causes of maternal mortality and severe morbidity. The American College of Obstetricians and Gynecologists recommends treatment of persistent severe hypertension because this has been shown to improve overall outcomes. Treatment remains inconsistent and may be influenced by patient-level sociodemographic and clinical characteristics.

OBJECTIVE

This study aimed to identify which factors are associated with nonadherence to an institutional protocol for the treatment of severe hypertension in pregnancy.

STUDY DESIGN

Retrospective cohort study of patients who had persistent severe hypertension (≥2 systolic blood pressures ≥160 mm Hg and/or diastolic blood pressures >110 mm Hg between 15 and 60 minutes apart) during their delivery hospitalization in 3 hospitals within an integrated health system from February 1, 2018 to March 1, 2020. Adherence to an institutional protocol was defined as receiving antihypertensive medication within 1 hour of a second severe blood pressure measurement. Demographic information, medical comorbidities, and delivery hospitalization characteristics were compared between women who received treatment based on institutional protocol and those who did not. Patient zone improvement plan codes were linked to neighborhood-level data from the US Census Bureau's American Community Survey to extract socioeconomic characteristics. A multivariable logistic regression was performed to evaluate factors associated with delayed treatment while adjusting for potential confounders.

RESULTS

Of the 996 patients included, 449 (45%) received treatment within 60 minutes and 547 (55%) did not. Having an elevated, nonsevere range blood pressure (adjusted odds ratio, 0.55; 95% confidence interval, 0.38-0.79) or a severe range blood pressure (adjusted odds ratio, 0.25; 95% confidence interval, 0.16-0.38) on admission, persistent severe hypertension ≥1 hour before or after delivery (adjusted odds ratio, 0.27; 95% confidence interval, 0.27-0.45), and chronic hypertension (adjusted odds ratio, 0.58; 95% confidence interval, 0.37-0.93) were associated with timely treatment. Hospital site (adjusted odds ratio, 1.97; 95% confidence interval, 1.18-3.28) and increasing gestational age (adjusted odds ratio, 1.14; 95% confidence interval, 1.07-1.21) were associated with nonadherence to treatment protocol. A subanalysis evaluating treatment in 344 (35%) patients who had a nonelevated blood pressure on admission showed that White race, persistent severe hypertension within 1 hour of delivery, increasing gestational age, body mass index, twin gestation, preferred language other than English or Spanish, and a higher neighborhood unemployment rate were associated with nonadherence to treatment protocol.

CONCLUSION

Several factors were associated with nonadherence to an institutional protocol for treatment of persistent severe hypertension. Provider bias may impact whether treatment is executed or not. Awareness of these risk factors may improve timely administration of antihypertensive medication in pregnant and postpartum patients.

Toward the elimination of race-based medicine: replace race with racism as preeclampsia risk factor

Pregnancy-related morbidity and mortality continue to disproportionately affect birthing people who identify as Black. The use of race-based risk factors in medicine exacerbates racial health inequities by insinuating a false conflation that fails to consider the underlying impact of racism. As we work toward health equity, we must remove race as a risk factor in our guidelines to address disparities due to racism. This includes the most recent US Preventive Services Taskforce, American College of Obstetricians and Gynecologists, and Society for Maternal-Fetal Medicine guidelines for aspirin prophylaxis in preeclampsia, where the risk factor for "Black race" should be replaced with "anti-Black racism." In this commentary, we reviewed the evidence that supports race as a sociopolitical construct and the health impacts of racism. We presented a call to action to remove racial determination in the guidelines for aspirin prophylaxis in preeclampsia and more broadly in our practice of medicine.

Mediterranean-Style Diet and Risk of Preeclampsia by Race in the Boston Birth Cohort

Background Preeclampsia is a major cause of maternal and fetal morbidity and mortality. Given its large public health burden, there is a need to identify modifiable factors that can be targeted for preeclampsia prevention. In this study, we examined whether a Mediterranean-style diet is protective for preeclampsia in a large cohort of racially and ethnically diverse, urban, low-income women. Methods and Results We used data from the Boston Birth Cohort. Maternal sociodemographic and dietary data were obtained via interview and food frequency questionnaire within 24 to 72 hours postpartum, respectively. Additional clinical information, including physician diagnoses of preexisting conditions and preeclampsia, were extracted from medical records. We derived a Mediterranean-style diet score from the food frequency questionnaire and performed logistic regression to examine the association of the Mediterranean-style diet score with preeclampsia. Of 8507 women in the sample, 848 developed preeclampsia. 47% were Black, 28% were Hispanic, and the remaining were White/Other. After multivariable adjustment, greatest adherence with MSD was associated with lower preeclampsia odds (adjusted odds ratio comparing tertile 3 to tertile 1, 0.78; 95% CI, 0.64-0.96). A subgroup analysis of Black women demonstrated a similar benefit with an adjusted odds ratio comparing tertile 3 to tertile 1 of 0.74 (95% CI, 0.76-0.96). Conclusions Self-report of higher adherence to a Mediterranean-style diet is associated with lower preeclampsia odds, and benefit of this diet is present among Black women as well.

Antidepressant use during pregnancy and development of preeclampsia: A focus on classes of action and specific transporters/receptors targeted by antidepressants

OBJECTIVE

The association between antidepressants and preeclampsia has been inconsistently reported. Given the compound-specific variable affinity for different transporters/receptors, their effect on preeclampsia risk could differ. Our study examined the risk of preeclampsia (and its subtypes) following exposure to different classes of antidepressants, also accounting for specific transporters/receptors targeted by antidepressants.

METHODS

We conducted a cohort study, combining data from the Netherlands Perinatal Registry and the PHARMO Database Network. Exposure to antidepressants was examined from conception to week 20 of gestation; extended use thereafter was also studied. Antidepressants were categorized according to classes [selective serotonin reuptake inhibitors (SSRIs), tricyclic antidepressants (TCAs), serotonin-norepinephrine reuptake inhibitors (SNRIs), monoamine oxidase inhibitors (MAOIs) and other antidepressants] and according to target transporters/receptors. Women not using any antidepressants during 15 months before delivery were included as reference.

RESULTS

We included 2,103 exposed and 95,376 reference women. Preeclampsia occurred in 70 exposed women (15 early-onset, 55 late-onset) and in 2,582 reference women (387 early-onset, 2,195 late-onset). TCA monotherapy (214 women) was associated with an increased risk of preeclampsia (n = 15, RR 2.46, 95% CI 1.51-4.02) and late-onset preeclampsia (n = 12, RR 2.41, 95% CI 1.39-4.17, early-onset could not be evaluated). No association was detected with SSRIs, SNRIs and MAOIs. We did observe an increased risk of early-onset preeclampsia following exposure to 5-HT2A antagonizing antidepressants (6/405 women, excluding TCA users, RR 3.56, 95% CI 1.60-7.94).

CONCLUSIONS

Our results support an increased risk of preeclampsia and the late-onset subtype among TCA users. The association between 5-HT2A antagonists and the early-onset subtype needs to be interpreted with caution based on the relatively small number of exposed cases.

The Preeclampsia Foundation: the voice and views of the patient and her family

Preeclampsia is a disease exclusive to pregnancy and the immediate postpartum period, occurring in 4.6% of pregnancies worldwide. Preeclampsia and other gestational hypertensive disorders can affect any pregnant woman. The consequences of developing this disease can lead to severe maternal and neonatal morbidities and mortalities, including fetal growth restriction, placental abruption, preterm birth, stillbirth, and maternal death. When pregnant women recover, they are at higher risk of long-term complications such as hypertension, stroke, heart failure, renal disease, and Alzheimer disease. The consequences extend to the offspring because they are at higher risk of cardiovascular diseases, and female offspring are at greater risk of developing preeclampsia when they become pregnant. For society, preeclampsia presents an economic burden related to the additional healthcare costs associated with low birthweight, prematurity, and adverse outcomes to the mother and baby. This article shares the unique perspective of affected women and their families, the effect preeclampsia has on us, and what we hope the healthcare system can deliver for our sisters and daughters in the future. Patients and their families established the Preeclampsia Foundation 21 years ago. Devoted to education and patient advocacy to raise awareness, improve healthcare practices, and catalyze research, we share some of the Foundation's realized strategies and achievements. We tell you our stories and struggles, and we issue a call to action for all stakeholders to help fulfill our vision for a world where hypertensive disorders of pregnancy no longer threaten the lives of mothers and their babies.

Risk factors for the development of new-onset and persistent postpartum preeclampsia: A case–control study in Ghana

Background:

Postpartum preeclampsia has been implicated in increasing hospital re-admissions, maternal morbidity, and mortality worldwide. The knowledge of the risk factors of postpartum preeclampsia would be helpful in formulating strategies to aid in the prevention, early diagnosis, and timely treatment of this disorder. Thus, this study aimed to identify the risk factors associated with the development of new-onset postpartum preeclampsia and persistent postpartum preeclampsia in the Ghanaian setting.

Methods:

This case–control study was conducted at the Obstetrics and Gynecology units of Komfo Anokye Teaching Hospital and the Kumasi Regional Hospital, both located in the Ashanti Region of Ghana. A total of 65 postpartum preeclamptic women (33 new-onset postpartum preeclampsia and 32 persistent postpartum preeclampsia) and 65 normotensive postpartum mothers were recruited from 48 h to 6 weeks post-delivery. Questionnaires were administered to assess the socio-demographic, lifestyle, obstetric characteristics, and past medical history of the study participants.

Results:

Physical inactivity (p < 0.0001), infrequent antenatal visits (p < 0.0001), analgesic use (p < 0.0001), and cesarean delivery (p = 0.021) were significantly associated with both the new-onset postpartum preeclampsia and persistent postpartum preeclampsia. Contraceptive use was significantly associated with the development of new-onset postpartum preeclampsia (p < 0.0001) while women with low-birthweight babies are also at high risk of developing persistent postpartum preeclampsia (p < 0.0001).

Conclusion:

Physical inactivity, infrequent antenatal visits, analgesic use, contraceptive use, and cesarean delivery are major predisposing risk factors for the development of postpartum preeclampsia. Screening using these risk factors, close monitoring and follow-up observation of women after delivery would be beneficial in identifying and managing postpartum preeclampsia.

No association between perinatal mood disorders and hypertensive pregnancies

Mental health disorders such as anxiety and/or depression are the most common mental health disorders seen among reproductive aged women and can increase during pregnancy. Many sociodemographic risk factors have been associated with anxiety and/or depression in pregnancy, which can lead to adverse maternal and infant outcomes including the risk of a hypertensive pregnancy. The current study prospectively examined self-reported anxiety, depression and stress in pregnant women without a history of fetal loss or mood disorders beginning at 20-26 weeks. At each study visit, circulating immune factors associated with perinatal mood disorders were measured in blood samples that were collected. A total of 65 women were eligible for data analysis, 26 of which had hypertensive pregnancies. There was not a significant difference in self-reported depression, anxiety or stress between hypertensive disorders of pregnancy and normotensive women. Black women were more likely to have a hypertensive pregnancy and develop a perinatal mood disorder compared to non-black women. Both the inflammatory cytokines interleukin-17 and tumor necrosis factor-alpha were increased in patients with perinatal mood disorders. However, additional research is needed in a larger sample to truly understand the relationship between these factors along with the underlying etiologies and the associated outcomes.

Severe thrombocytopenia and microangiopathic hemolytic anemia in pregnancy: A guide for the consulting hematologist

A hematologist receives a call from a maternal-fetal medicine (MFM) physician about a previously healthy patient who became ill at 25 weeks' gestation. Her mental status is deteriorating. There are signs of fetal distress. Platelet count and hemoglobin are falling. The MFM physician is considering the hemolysis, elevated liver enzymes and low platelet count (HELLP) syndrome. For the hematologist, everything seems unfamiliar. Our goal is to provide hematologists with the fundamental knowledge required for understanding and managing these patients who become suddenly and seriously ill during pregnancy and in whom thrombocytopenia and microangiopathic hemolytic anemia are part of their presentation.

Use of Race, Ethnicity, and National Origin in Studies Assessing Cardiovascular Risk in Women With a History of Hypertensive Disorders of Pregnancy

Women with a history of hyperBtensive disorders of pregnancy (HDP) are at particularly high risk for cardiovascular disease (CVD) and CVD-related death, and certain racial and ethnic subpopulations are disproportionately affected by these conditions. We examined the use of race, ethnicity, and national origin in observational studies assessing CVD morbidity and mortality in women with a history of HDP. A total of 124 studies, published between 1976 and 2021, were reviewed. We found that white women were heavily overrepresented, encompassing 53% of all participants with HDP. There was limited and heterogeneous reporting of race and ethnicity information across studies and only 27 studies reported including race and/or ethnicity variables in at least 1 statistical analysis. Only 2 studies mentioned the use of these variables as a strength; several others (k = 18) reported a lack of diversity among participants as a study limitation. Just over half of included articles (k = 68) reported at least 1 sociodemographic variable other than race and ethnicity (eg, marital status and income); however, none investigated how they might have worked synergistically or antagonistically with race and/or ethnicity to influence participants' risk of CVD. These findings highlight significant areas for improvement in cardiovascular obstetrics research, including the need for more robust and standardized methods for collecting, reporting, and using sociodemographic information. Future studies of CVD risk in women with a history of HDP should explicitly examine racial and ethnic differences and use an intersectional approach.

Nativity-Related Disparities in Preeclampsia and Cardiovascular Disease Risk Among a Racially Diverse Cohort of US Women

IMPORTANCE

Preeclampsia is an independent risk factor for future cardiovascular disease and disproportionally affects non-Hispanic Black women. The association of maternal nativity and duration of US residence with preeclampsia and other cardiovascular risk factors is well described among non-Hispanic Black women but not among women of other racial and ethnic groups.

OBJECTIVE

To examine differences in cardiovascular risk factors and preeclampsia prevalence by race and ethnicity, nativity, and duration of US residence among Hispanic, non-Hispanic Black, and non-Hispanic White women.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional analysis of the Boston Birth Cohort included a racially diverse cohort of women who had singleton deliveries at the Boston Medical Center from October 1, 1998, to February 15, 2016. Participants self-identified as Hispanic, non-Hispanic Black, or non-Hispanic White. Data were analyzed from March 1 to March 31, 2021.

EXPOSURES

Maternal nativity and duration of US residence (<10 vs ≥10 years) were self-reported.

MAIN OUTCOME AND MEASURES

Diagnosis of preeclampsia, the outcome of interest, was retrieved from maternal medical records.

RESULTS

A total of 6096 women (2400 Hispanic, 2699 non-Hispanic Black, and 997 non-Hispanic White) with a mean (SD) age of 27.5 (6.3) years were included in the study sample. Compared with Hispanic and non-Hispanic White women, non-Hispanic Black women had the highest prevalence of chronic hypertension (204 of 2699 [7.5%] vs 65 of 2400 [2.7%] and 28 of 997 [2.8%], respectively), obesity (658 of 2699 [24.4%] vs 380 of 2400 [15.8%] and 152 of 997 [15.2%], respectively), and preeclampsia (297 of 2699 [11.0%] vs 212 of 2400 [8.8%] and 71 of 997 [7.1%], respectively). Compared with their counterparts born outside the US, US-born women in all 3 racial and ethnic groups had a significantly higher prevalence of obesity (Hispanic women, 132 of 556 [23.7%] vs 248 of 1844 [13.4%]; non-Hispanic Black women, 444 of 1607 [27.6%] vs 214 of 1092 [19.6%]; non-Hispanic White women, 132 of 776 [17.0%] vs 20 of 221 [9.0%]), smoking (Hispanic women, 98 of 556 [17.6%] vs 30 of 1844 [1.6%]; non-Hispanic Black women, 330 of 1607 [20.5%] vs 53 of 1092 [4.9%]; non-Hispanic White women, 382 of 776 [49.2%] vs 42 of 221 [19.0%]), and severe stress (Hispanic women, 76 of 556 [13.7%] vs 85 of 1844 [4.6%]; non-Hispanic Black women, 231 of 1607 [14.4%] vs 120 of 1092 [11.0%]; non-Hispanic White women, 164 of 776 [21.1%] vs 26 of 221 [11.8%]). After adjusting for sociodemographic and cardiovascular risk factors, birth status outside the US (adjusted odds ratio [aOR], 0.74 [95% CI, 0.55-1.00]) and shorter duration of US residence (aOR, 0.62 [95% CI, 0.41-0.93]) were associated with lower odds of preeclampsia among non-Hispanic Black women. However, among Hispanic and non-Hispanic White women, maternal nativity (aOR for Hispanic women, 1.07 [95% CI, 0.72-1.60]; aOR for non-Hispanic White women, 0.98 [95% CI, 0.49-1.96]) and duration of US residence (aOR for Hispanic women <10 years, 1.04 [95% CI, 0.67-1.59]; aOR for non-Hispanic White women <10 years, 1.20 [95% CI, 0.48-3.02]) were not associated with preeclampsia.

CONCLUSIONS AND RELEVANCE

Nativity-related disparities in preeclampsia persisted among non-Hispanic Black women but not among Hispanic and non-Hispanic White women after adjusting for sociodemographic and cardiovascular risk factors. Further research is needed to explore the interplay of factors contributing to nativity-related disparities in preeclampsia, particularly among non-Hispanic Black women.

Frailty in ethnic minority women

In majority populations in high- and middle-income countries, women live longer yet experience higher levels of frailty than men of the same age. It is unclear whether this 'sex-frailty paradox' is present in ethnic minority populations. In this narrative review, we explore biological, behavioural and social factors associated with mortality, morbidity and frailty in women, particularly ethnic minority women. We ascertain that natural menopause occurs earlier in women of particular ethnicities. Ethnic minority women (living in high-income countries) have more children and higher rates of chronic disease and disability, all of which are associated with frailty. In some ethnic minorities, women are less likely to engage in deleterious health behaviours such as smoking and alcohol consumption. However, in others the reverse is true. Women from migrant ethnic minorities tend to have lower levels of physical activity. With time, they can also adopt adverse behavioural patterns of the majority population. Although the evidence is sparse, sex differences in health reporting and social assets, as well as gender roles, are likely to contribute to sex differences in frailty in ethnic minorities. Overall, ethnic minority women are a particularly vulnerable group, but the majority of risk factors for frailty appear to be mutable rather than fixed. Future research may examine interventions that target frailty in different races and ethnicities at individual, population and global levels.

Aspirin Use to Prevent Preeclampsia and Related Morbidity and Mortality: US Preventive Services Task Force Recommendation Statement

IMPORTANCE

Preeclampsia is one of the most serious health problems that affect pregnant persons. It is a complication in approximately 4% of pregnancies in the US and contributes to both maternal and infant morbidity and mortality. Preeclampsia also accounts for 6% of preterm births and 19% of medically indicated preterm births in the US. There are racial and ethnic disparities in the prevalence of and mortality from preeclampsia. Non-Hispanic Black women are at greater risk for developing preeclampsia than other women and experience higher rates of maternal and infant morbidity and perinatal mortality.

OBJECTIVE

To update its 2014 recommendation, the USPSTF commissioned a systematic review to evaluate the effectiveness of low-dose aspirin use to prevent preeclampsia.

POPULATION

Pregnant persons at high risk for preeclampsia who have no prior adverse effects with or contraindications to low-dose aspirin.

EVIDENCE ASSESSMENT

The USPSTF concludes with moderate certainty that there is a substantial net benefit of daily low-dose aspirin use to reduce the risk for preeclampsia, preterm birth, small for gestational age/intrauterine growth restriction, and perinatal mortality in pregnant persons at high risk for preeclampsia.

RECOMMENDATION

The USPSTF recommends the use of low-dose aspirin (81 mg/d) as preventive medication for preeclampsia after 12 weeks of gestation in persons who are at high risk for preeclampsia. (B recommendation).

Association Between TLR4 Gene Polymorphisms and Risk of Preeclampsia: Systematic Review and Meta-Analysis

BACKGROUND Toll-like receptor 4 (TLR4) plays a pivotal role in the innate immune response and is hyperactivated in preeclampsia (PE). Several researchers have published conflicting evidence for TLR4 rs4986790 and rs4986791 single nucleotide polymorphisms (SNPs) as risk factors for PE. The present meta-analysis was conducted to obtain a more definitive conclusion about the effects of these SNPs on PE susceptibility. MATERIAL AND METHODS To determine the correlation between rs4986790 and rs4986791 polymorphisms in the TLR4 gene and susceptibility to PE, the PubMed, Web of Science, EMBASE, Chinese National Knowledge Infrastructure, and Chinese WANFANG databases were searched for eligible articles. Statistical analysis was performed with STATA software, version 12.0. Pooled odds ratios with corresponding 95% confidence intervals (CIs) were extracted for assessment of correlation strength. RESULTS We identified 5 studies including 578 cases and 631 controls for the rs4986790 SNP and 4 studies including 469 cases and 457 controls for the rs4986791 SNP, mainly from a White population. The pooled analyses showed no statistical relationship between the polymorphisms rs4986790 and rs4986791 and PE susceptibility in 5 genetic models (all P>0.05). Moreover, the allelic and dominant gene models of rs4986790 and the allelic, heterozygous, and dominant gene models of rs4986791 had high heterogeneity. The sensitivity analysis explored potential sources of heterogeneity and confirmed the findings of this meta-analysis. CONCLUSIONS TLR4 rs4986790 and rs4986791 polymorphisms may not be implicated in PE susceptibility, primarily in a White population. More high-quality studies of genetic associations with PE are warranted.

Racial Disparities in Cardiovascular Complications With Pregnancy-Induced Hypertension in the United States

[Figure: see text].

MMP-2 and MMP-9 Polymorphisms and Preeclampsia Risk in Tunisian Arabs: A Case-Control Study

The abnormal production of matrix metalloproteinases (MMPs), especially MMP-9 and MMP-2, plays a pivotal role in hypertensive disorders of pregnancy, and as such, can influence the development of preeclampsia. These alterations may result from functional genetic polymorphisms in the promoter region of MMP-9 and MMP-2 genes, which modify MMP-9 and MMP-2 expression. We investigated the association of MMP-9 polymorphism rs3918242 (-1562 C>T) and MMP-2 polymorphism rs2285053 (-735 C>T) with the risk of preeclampsia. This case–control study was conducted on 345 women with preeclampsia and 281 age-matched women with normal pregnancies from Tunisian hospitals. Genomic DNA was extracted from whole blood collected at delivery. Genotypes for -1562 C>T and -735 C>T polymorphisms were performed using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). An increased frequency of heterozygous MMP-9 -1562 C/T genotype carriers was observed in women with preeclampsia compared to healthy controls (p = 0.03). In contrast, the MMP-2 -735 C>T polymorphism was not significantly different regarding frequency distribution of the allele and genotype between healthy pregnant women and women with preeclampsia. Our study suggests that the MMP-9 -1562 C/T variant, associated with high MMP-9 production, could be a genetic risk factor for preeclampsia in Tunisian women.

Preeclampsia Prevalence, Risk Factors, and Pregnancy Outcomes in Sweden and China

IMPORTANCE

Preeclampsia is a leading cause of maternal and perinatal morbidity and mortality worldwide. Within-country studies have reported racial differences in the presentation and outcome, but little is known about differences between countries.

OBJECTIVE

To compare preeclampsia prevalence, risk factors, and pregnancy outcomes between the Swedish and Chinese populations.

DESIGN, SETTING, AND PARTICIPANTS

This cross-sectional study compared deliveries from the Swedish national Medical Birth Register (2007-2012) and the China Labor and Delivery Survey (2015-2016). The Swedish Medical Birth Register records maternal, pregnancy, and neonatal information for nearly all deliveries in Sweden. The China Labor and Delivery Survey was conducted throughout China, and these data were reweighted to enable national comparisons. Participants included 555 446 deliveries from Sweden and 79 243 deliveries from China. Data management and analysis was conducted from November 2018 to August 2020 and revised in February to March 2021.

EXPOSURES

Maternal characteristics, parity, multiple gestation, chronic and gestational diabetes, cesarean delivery.

MAIN OUTCOMES AND MEASURES

Preeclampsia prevalence and risk factors, overall and for mild and severe forms and rates of adverse neonatal outcomes compared with pregnancies with no gestational hypertension.

RESULTS

The 555 446 Swedish pregnancies and 79 243 Chinese pregnancies had mean (SD) maternal age of 30.9 (5.3) years and 28.6 (4.6) years, respectively. The overall prevalence of preeclampsia was similar in Sweden and China, 16 068 (2.9%) and 1803 (2.3%), respectively, but with 5222 cases (32.5%) considered severe in Sweden and 1228 cases (68.1%) considered severe in China. Obesity (defined as BMI ≥28 in China and BMI ≥30 in Sweden) was a stronger risk factor in China compared with Sweden (China: odds ratio [OR], 5.12; 95% CI, 3.82-6.86; Sweden: OR, 3.49; 95% CI, 3.31-3.67). Nulliparity had a much stronger association with severe preeclampsia in Sweden compared with China (Sweden: OR, 3.91; 95% CI, 3.65-4.18; China: OR, 1.65; 95% CI, 1.20-2.25). The overall stillbirth rate for singleton in China was more than 3-fold higher than in Sweden (846/77 512[1.1%] vs 1753/547 219 [0.3%], P < .001), and 10-fold higher among women with preeclampsia (66/1652 [4.6%] vs 60/14 499[0.4%], P < .001).

CONCLUSIONS AND RELEVANCE

In this study, the prevalence rates of preeclampsia in Sweden and China were similar, but women in China had more severe disease and worse pregnancy outcomes than women in Sweden. The associations of obesity and nulliparity with preeclampsia suggest a role for lifestyle and health care factors but may reflect some differences in pathophysiology. These findings have relevance for current efforts to identify high-risk pregnancies and early serum markers because the value of risk prediction models and biomarkers may be population specific.

Neurology of Preeclampsia and Related Disorders: an Update in Neuro-obstetrics

PURPOSE OF REVIEW

Preeclampsia and related hypertensive disorders of pregnancy affect up to 10% of pregnancies. Neurological complications are common and neurologists often become involved in the care of obstetric patients with preeclampsia. Here, we review the definition(s), epidemiology, clinical features, and pathophysiology of preeclampsia, focusing on maternal neurological complications and headache as a common presenting symptom of preeclampsia.

RECENT FINDINGS

Neurological symptoms are early and disease-defining features of preeclampsia. Neurological complications of preeclampsia may include headaches, visual symptoms, cerebral edema, seizures, or acute cerebrovascular disorders such as intracerebral hemorrhage or reversible cerebral vasoconstriction syndrome. A history of migraine is an independent risk factor for vascular diseases during pregnancy, including preeclampsia and maternal stroke. The pathophysiology of both preeclampsia and migraine is complex, and the mechanisms linking the two are not fully understood. Overlapping clinical and pathophysiological features of migraine and preeclampsia include inflammation, vascular endothelial dysfunction, and changes in vasoreactivity. Neurological complications are recognized as a major contributor to maternal morbidity and mortality. Pregnant and postpartum women commonly present with headache, and red flags in the clinical history and examination should prompt urgent neuroimaging and laboratory evaluation. A focused headache history should be elicited from patients as part of routine obstetrical care to identify patients at an increased risk of preeclampsia and related hypertensive disorders of pregnancy. Collaborative models of care and scientific investigation in the emerging field of neuro-obstetrics have the common goal of reducing the risk of maternal neurological morbidity and mortality from preeclampsia.

Relationship of Preeclampsia With Maternal Place of Birth and Duration of Residence Among Non-Hispanic Black Women in the United States

BACKGROUND

Preeclampsia is one of the leading causes of maternal mortality in the United States. It disproportionately affects non-Hispanic Black (NHB) women, but little is known about how preeclampsia and other cardiovascular disease risk factors vary among different subpopulations of NHB women in the United States. We investigated the prevalence of preeclampsia by nativity (US born versus foreign born) and duration of US residence among NHB women.

METHODS

We analyzed cross-sectional data from the Boston Birth Cohort (1998-2016), with a focus on NHB women. We performed multivariable logistic regression to investigate associations between preeclampsia, nativity, and duration of US residence after controlling for potential confounders.

RESULTS

Of 2697 NHB women, 40.5% were foreign born. Relative to them, US-born NHB women were younger, in higher percentage current smokers, had higher prevalence of obesity (body mass index ≥30 kg/m2) and maternal stress, but lower educational level. The age-adjusted prevalence of preeclampsia was 12.4% and 9.1% among US-born and foreign-born women, respectively. When further categorized by duration of US residence, the prevalence of all studied cardiovascular disease risk factors except for diabetes was lower among foreign-born NHB women with <10 versus ≥10 years of US residence. Additionally, the odds of preeclampsia in foreign-born NHB women with duration of US residence <10 years was 37% lower than in US-born NHB women. In contrast, the odds of preeclampsia in foreign-born NHB women with duration of US residence ≥10 years was not significantly different from that of US-born NHB women after adjusting for potential confounders.

CONCLUSIONS

The prevalence of preeclampsia and other cardiovascular disease risk factors is lower in foreign-born than in US-born NHB women. The healthy immigrant effect, which typically results in health advantages for foreign-born women, appears to wane with longer duration of US residence (≥10 years). Further research is needed to better understand these associations.

Racial Differences in Postpartum Blood Pressure Trajectories Among Women After a Hypertensive Disorder of Pregnancy

IMPORTANCE

Maternal morbidity and mortality are increasing in the United States, most of which occur post partum, with significant racial disparities, particularly associated with hypertensive disorders of pregnancy. Blood pressure trajectory after a hypertensive disorder of pregnancy has not been previously described.

OBJECTIVES

To describe the blood pressure trajectory in the first 6 weeks post partum after a hypertensive disorder of pregnancy and to evaluate whether blood pressure trajectories differ by self-reported race.

DESIGN, SETTING, AND PARTICIPANTS

This prospective cohort study included deliveries between January 1, 2018, and December 31, 2019. Women with a clinical diagnosis of a hypertensive disorder of pregnancy were enrolled in a postpartum remote blood pressure monitoring program at the time of delivery and were followed up for 6 weeks. Statistical analysis was performed from April 6 to 17, 2020.

MAIN OUTCOMES AND MEASURES

Mixed-effects regression models were used to display blood pressure trajectories in the first 6 weeks post partum.

RESULTS

A total of 1077 women were included (mean [SD] age, 30.2 [5.6] years; 804 of 1017 White [79.1%] and 213 of 1017 Black [20.9%]). Systolic and diastolic blood pressures were found to decrease rapidly in the first 3 weeks post partum, with subsequent stabilization (at 6 days post partum: mean [SD] peak systolic blood pressure, 146 [13] mm Hg; mean [SD] peak diastolic blood pressure, 95 [10] mm Hg; and at 3 weeks post partum: mean [SD] peak systolic blood pressure, 130 [12] mm Hg; mean [SD] peak diastolic blood pressure, 85 [9] mm Hg). A significant difference was seen in blood pressure trajectory by race, with both systolic and diastolic blood pressure decreasing more slowly among Black women compared with White women (mean [SD] peak systolic blood pressure at 1 week post partum: White women, 143 [14] mm Hg vs Black women, 146 [13] mm Hg; P = .01; mean [SD] peak diastolic blood pressure at 1 week post partum: White women, 92 [9] mm Hg vs Black women, 94 [9] mm Hg; P = .02; and mean [SD] peak systolic blood pressure at 3 weeks post partum: White women, 129 [11] mm Hg vs Black women, 136 [15] mm Hg; P < .001; mean [SD] peak diastolic blood pressure at 3 weeks post partum: White women, 84 [8] mm Hg vs Black women, 91 [13] mm Hg; P < .001). At the conclusion of the program, 126 of 185 Black women (68.1%) compared with 393 of 764 White women (51.4%) met the criteria for stage 1 or stage 2 hypertension (P < .001).

CONCLUSIONS AND RELEVANCE

This study found that, in the postpartum period, blood pressure decreased rapidly in the first 3 weeks and subsequently stabilized. The study also found that, compared with White women, Black women had a less rapid decrease in blood pressure, resulting in higher blood pressure by the end of a 6-week program. Given the number of women with persistent hypertension at the conclusion of the program, these findings also appear to support the importance of ongoing postpartum care beyond the first 6 weeks after delivery.

Cardiovascular severe maternal morbidity in pregnant and postpartum women: development and internal validation of risk prediction models

OBJECTIVES

To develop and internally validate risk prediction models identifying women at risk for cardiovascular severe maternal morbidity (CSMM).

DESIGN

A retrospective cohort study.

SETTING

An obstetric teaching hospital between 2007 and 2017.

POPULATION

A total of 89 681 delivery hospitalisations.

METHODS

We created and evaluated two models, one predicting CSMM at delivery (delivery model) and the other predicting CSMM postpartum following discharge from delivery hospitalisation (postpartum CSMM). We assessed model discrimination and calibration and used bootstrapping for internal validation.

MAIN OUTCOME MEASURES

Cardiovascular severe maternal morbidity comprised the following confirmed conditions: pulmonary oedema/acute heart failure, myocardial infarction, aneurysm, cardiac arrest/ventricular fibrillation, heart failure/arrest during surgery or procedure, cerebrovascular disorders, cardiogenic shock, conversion of cardiac rhythm and difficult-to-control severe hypertension.

RESULTS

The delivery model contained 11 variables and 3 interaction terms. The strongest predictors were gestational hypertension, chronic hypertension, multiple gestation, cardiac lesions or valvular heart disease, maternal age ≥40 years and history of poor pregnancy outcome. The postpartum model comprised eight variables. The strongest predictors were severe pre-eclampsia, non-Hispanic Black race/ethnicity, chronic hypertension, gestational hypertension, non-severe pre-eclampsia and maternal age ≥40 years at delivery. The delivery and postpartum models had an area under the receiver operating characteristic curve of 0.87 (95% CI 0.85-0.89) and 0.85 (95% CI 0.80-0.90), respectively. Both models were adequately calibrated and performed well on internal validation.

CONCLUSIONS

These tools may help providers to identify women at highest risk of CSMM and enable future prevention measures.

TWEETABLE ABSTRACT

Risk assessment tools for cardiovascular severe maternal morbidity were developed and internally validated.