Racial and Ethnic Disparities among Pregnancies with Chronic Hypertension and Adverse Outcomes

OBJECTIVE

 We aimed to ascertain whether the risk of adverse pregnancy outcomes in the United States among individuals with chronic hypertension differed by maternal race and ethnicity and to assess the temporal trend.

STUDY DESIGN

 Population-based retrospective study using the U.S. Vital Statistics datasets evaluated pregnancies with chronic hypertension, singleton live births that delivered at 24 to 41 weeks. The coprimary outcomes were a composite maternal adverse outcome (preeclampsia, primary cesarean delivery, intensive care unit admission, blood transfusion, uterine rupture, or unplanned hysterectomy) and a composite neonatal adverse outcome (preterm birth, small for gestational age, Apgar's score <5 at 5 minutes, assisted ventilation> 6 hours, seizure, or death). Multivariable Poisson regression models were used to estimate adjusted relative risks (aRRs) and 95% confidence intervals (CIs).

RESULTS

 Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased from 1.6 to 2.2%. After multivariable adjustment, an increased risk for the composite maternal adverse outcome was found in Black (aRR = 1.10, 95% CI = 1.09-1.11), Hispanic (aRR = 1.04, 95% CI = 1.02-1.05), and Asian/Pacific Islander (aRR = 1.07, 95% CI = 1.05-1.10), compared with White individuals. Compared with White individuals, the risk of the composite neonatal adverse outcome was higher in Black (aRR = 1.39, 95% CI = 1.37-1.41), Hispanic (aRR = 1.15, 95% CI = 1.13-1.16), Asian/Pacific Islander (aRR = 1.34, 95% CI = 1.31-1.37), and American Indian (aRR = 1.12, 95% CI = 1.07-1.17). The racial and ethnic disparity remained unchanged during the study period.

CONCLUSION

 We found a racial and ethnic disparity with maternal and neonatal adverse outcomes in pregnancies with chronic hypertension that remained unchanged throughout the study period.

KEY POINTS

· Between 2014 and 2019, the rate of chronic hypertension in pregnancy increased.. · Among people with chronic hypertension, there are racial and ethnic disparities in adverse outcomes.. · Black, Hispanic, and Asian/Pacific Islander have a higher risk of the adverse neonatal outcomes..

Maternal Hypertension-Related Genotypes and Congenital Heart Defects

BACKGROUND

Maternal hypertension has been associated with congenital heart defect occurrence in several studies. We assessed whether maternal genotypes associated with this condition were also associated with congenital heart defect occurrence.

METHODS

We used data from the National Birth Defects Prevention Study to identify non-Hispanic white (NHW) and Hispanic women with (cases) and without (controls) a pregnancy in which a select simple, isolated heart defect was present between 1999 and 2011. We genotyped 29 hypertension-related single nucleotide polymorphisms (SNPs). We conducted logistic regression analyses separately by race/ethnicity to assess the relationship between the presence of any congenital heart defect and each SNP and an overall blood pressure genetic risk score (GRS). All analyses were then repeated to assess 4 separate congenital heart defect subtypes.

RESULTS

Four hypertension-related variants were associated with congenital heart defects among NHW women (N = 1,568 with affected pregnancies). For example, 1 intronic variant in ARHGAP2, rs633185, was associated with conotruncal defects (odds ratio [OR]: 1.3, 95% confidence interval [CI]: 1.1-1.6). Additionally, 2 variants were associated with congenital heart defects among Hispanic women (N = 489 with affected pregnancies). The GRS had a significant association with septal defects (OR: 2.1, 95% CI: 1.2-3.5) among NHW women.

CONCLUSIONS

We replicated a previously reported association between rs633185 and conotruncal defects. Although additional hypertension-related SNPs were also associated with congenital heart defects, more work is needed to better understand the relationship between genetic risk for maternal hypertension and congenital heart defects occurrence.

Cardiac disease in pregnancy and the multidisciplinary team: the Wellington experience

AIM

To define the range and severity of cardiac disease in pregnant women in New Zealand, as well as the maternal and neonatal morbidity and mortality compared with the background obstetric population.

METHODS

We retrospectively audited pregnant women with cardiac comorbidity seen by a multidisciplinary team at a tertiary referral centre consisting of midwives, cardiologists, obstetricians and anaesthetists in 2016-2017.

RESULTS

Seventy-two women were referred to the multidisciplinary team. The most common referral reasons were arrhythmia (n=20, 27.8%), congenital anomalies (n=19, 26.4%) and palpitations (n=10, 13.9%). Fifty-two of these women were found to be at increased risk of morbidity or mortality. A specific delivery plan was devised for 37 of these women (69.8%). There was no serious maternal morbidity or mortality. Instrumental delivery rates were higher for women with cardiac comorbidity than the background obstetric population (19.2% vs 10.8%, p=0.049), however, neonatal admissions were not increased (11.5% compared with 16.5%).

CONCLUSION

Multidisciplinary review of obstetric patients with cardiac disease provides an important service to ensure risk modification prior to conception and throughout pregnancy and the puerperium.

Longitudinal changes in vascular function parameters in pregnant women with chronic hypertension and association with adverse outcome: a cohort study

OBJECTIVES

Raised vascular function measures are associated with adverse maternal and perinatal outcomes in low-risk pregnancy. This study aimed to evaluate the association between longitudinal vascular function parameters and adverse outcome in pregnant women with chronic hypertension, and to assess whether these measures vary according to baseline parameters such as black ethnicity.

METHODS

This was a nested cohort study of women with chronic hypertension and a singleton pregnancy recruited to the PANDA (Pregnancy And chronic hypertension: NifeDipine vs lAbetalol as antihypertensive treatment) study at one of three UK maternity units. Women had serial pulse-wave analyses performed using the Arteriograph®, while in a sitting position, from 12 weeks' gestation onwards. Statistical analysis was performed using random-effects logistic regression models. Longitudinal vascular parameters were compared between women who developed superimposed pre-eclampsia (SPE) and those who did not, between women who delivered a small-for-gestational-age (SGA) infant (birth weight < 10^th centile) and those who delivered an infant with birth weight ≥ 10^th centile and between women of black ethnicity and those of non-black ethnicity.

RESULTS

The cohort included 97 women with chronic hypertension and a singleton pregnancy, of whom 90% (n = 87) were randomized to antihypertensive treatment and 57% (n = 55) were of black ethnicity, with up to six (mean, three) longitudinal vascular function assessments. SPE was diagnosed in 18% (n = 17) of women and 30% (n = 29) of infants were SGA. In women who developed subsequent SPE, compared with those who did not, mean brachial systolic blood pressure (SBP) (148 mmHg vs 139 mmHg; P = 0.002), mean diastolic blood pressure (DBP) (87 mmHg vs 82 mmHg; P = 0.01), mean central aortic pressure (139 mmHg vs 128 mmHg; P = 0.001) and mean augmentation index (AIx-75) (29% vs 22%; P = 0.01) were significantly higher across gestation. In women who delivered a SGA infant compared to those who delivered an infant with birth weight ≥ 10^th centile, mean brachial SBP (146 mmHg vs 138 mmHg; P = 0.001), mean DBP (86 mmHg vs 82 mmHg; P = 0.01), mean central aortic pressure (137 mmHg vs 127 mmHg; P < 0.0001) and mean pulse-wave velocity (9.1 m/s vs 8.5 m/s; P = 0.02) were higher across gestation. No longitudinal differences were found in vascular function parameters in women of black ethnicity compared with those of non-black ethnicity.

CONCLUSION

There were persistent differences in vascular function parameters and brachial blood pressure throughout pregnancy in women with chronic hypertension who later developed adverse maternal or perinatal outcome. Further investigation into the possible clinical use of these findings is warranted. Copyright © 2018 ISUOG. Published by John Wiley & Sons Ltd.

Secular Increases in Spontaneous Subarachnoid Hemorrhage during Pregnancy: A Nationwide Sample Analysis

IMPORTANCE

Understanding of the epidemiology, outcomes, and management of spontaneous subarachnoid hemorrhage (sSAH) during pregnancy is limited. Small, single center series suggest a slight increase in morbidity and mortality.

OBJECTIVE

To determine if incidence of sSAH in pregnancy is increasing nationally and also to study the outcomes for this patient population.

DESIGN, SETTING, AND PARTICIPANTS

A retrospective analysis was performed utilizing the Nationwide Inpatient Sample (NIS) and Healthcare Cost and Utilization Project for the years 2002-2014 for sSAH hospitalizations. The NIS is a large administrative database designed to produce nationally weighted estimates. Female patients age 15-49 with sSAH were identified using the International Classification of Diseases, 9th Revision, Clinical Modification code 430. Pregnancy and maternal diagnosis were identified using pregnancy related ICD codes validated by previous studies. The Cochran-Armitage trend test and parametric tests were utilized to analyze temporal trends and group comparisons. Main Outcomes and Measures: National trend for incidence of sSAH in pregnancy, age, and race/ethnicity as well as associated risk factors and outcomes.

RESULTS

During the time period, there were 73,692 admissions for sSAH in women age 15-49 years, of which 3978 (5.4%) occurred during pregnancy. The proportion of sSAH during pregnancy hospitalizations increased from 4.16 % to 6.33% (P-_Trend < .001) during the 12 years of the study. African-American women (8.19%) and Hispanic (7.11%) had higher rates of sSAH during pregnancy than whites (3.83%). In the NIS data, the incidence of sSAH increased from 5.4/100,000 deliveries (2002) to 8.5/100,000 deliveries (2014; P-_Trend < .0001). The greatest increase in sSAH was noted to be among pregnant African-American women from (13.4 [2002]) to (16.39 [2014]/100,000 births). Mortality was lower in pregnant women (7.69% versus 17.37%, P < .0001). Pregnant women had a higher likelihood of being discharged to home (69.78% versus 53.66%, P < .0001) and lower likelihood of discharge to long term facility (22.4% versus 28.7%, P < .0001) than nonpregnant women after sSAH hospitalization.

CONCLUSIONS AND RELEVANCE

There is an upward trend in the incidence of sSAH occurring during pregnancy. There was disproportionate increase in incidence of sSAH in the African American and younger mothers. Outcomes were better for both pregnant and nonpregnant women treated at teaching hospitals and in pregnant women in general as compared to nonpregnant women.

Chronic hypertension and adverse pregnancy outcome: a cohort study

OBJECTIVE

To examine the association between chronic hypertension (CH) and a wide range of adverse pregnancy outcomes after adjustment for confounding factors in obstetric history and maternal characteristics.

METHODS

This was a prospective screening study for adverse pregnancy outcomes in women with singleton pregnancy attending their first routine hospital visit at 11 + 0 to 13 + 6 weeks' gestation. Data on maternal characteristics, medical and obstetric history and pregnancy outcome were collected. Regression analysis was performed to examine the association between CH and adverse pregnancy outcomes, including late miscarriage, stillbirth, pre-eclampsia (PE), gestational diabetes mellitus (GDM), spontaneous and iatrogenic preterm birth (PTB), small-for-gestational-age (SGA) neonate, large-for-gestational-age (LGA) neonate and elective and emergency Cesarean section (CS).

RESULTS

The study population of 109 932 pregnancies included 1417 (1.3%) women with CH. After adjusting for potential confounding variables from maternal characteristics, medical and obstetric history, CH was associated with increased risk of stillbirth (odds ratio (OR), 2.38 (95% CI, 1.51-3.75)), PE (OR, 5.76 (95% CI, 4.93-6.73)), SGA (OR, 2.06 (95% CI, 1.79-2.39)), GDM (OR, 1.61 (95% CI, 1.27-2.05)), iatrogenic PTB < 37 weeks (OR, 3.73 (95% CI, 3.07-4.53)) and elective CS (OR, 1.79 (95% CI, 1.52-2.11)), decreased risk of LGA (OR, 0.65 (95% CI, 0.53-0.78)) and had no significant effect on late miscarriage, spontaneous PTB or emergency CS.

CONCLUSION

CH should be combined with other maternal characteristics and medical and obstetric history when calculating an individualized adjusted risk for adverse pregnancy complications. CH increases the risk of stillbirth, PE, SGA, GDM, iatrogenic PTB and elective CS and reduces the risk for LGA. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

Genetic variations in the annexin A5 gene and the risk of pregnancy-related venous thrombosis

BACKGROUND

Annexin A5 is a natural anticoagulant assumed to have thrombomodulary functions as it shields phospholipid layers from coagulation complexes. It was recently shown that the M2 haplotype within the annexin A5 gene (ANXA5) promoter reduces the transcriptional activity of the gene. In a previous report, the M2 haplotype was found to be associated with pregnancy-related venous thrombosis (VT).

OBJECTIVES

To investigate whether the M1 or M2 haplotypes or other genetic variations in ANXA5 are associated with pregnancy-related VT.

PATIENTS/METHODS

We investigated samples from 313 cases and 353 controls included in the VIP study, which is a case-control study of pregnancy-related VT. We analyzed tag single nucleotide polymorphisms (SNPs) selected from the CEU population (Utah Residents with Northern and Western European Ancestry) of HapMap and the M1 and the M2 haplotypes of the promoter. Odds ratios for VT were calculated for each haplotype with the wild type as the reference and for each tag SNP with the most common genotype as reference.

RESULTS

We did not find any association between genetic variants in ANXA5 and the risk of pregnancy related VT, but some of the genetic variants were not in Hardy-Weinberg equilibrium.

CONCLUSION

Neither the M1/M2 haplotypes nor the tag SNPs in ANXA5 were convincingly associated with pregnancy related VT, but other studies in this field are needed.

Relations of plasma polyunsaturated Fatty acids with blood pressures during the 26th and 28th week of gestation in women of Chinese, Malay, and Indian ethnicity

Observational and intervention studies have reported inconsistent results of the relationship between polyunsaturated fatty acids (PUFAs) and hypertension during pregnancy. Here, we examined maternal plasma concentrations of n-3 and n-6 PUFAs between the 26th and the 28th week of gestation in relation to blood pressures and pregnancy-associated hypertension.We used data from a birth cohort study of 751 Chinese, Malay, and Indian women. Maternal peripheral systolic blood pressure (SBP) and diastolic blood pressure (DBP) were taken from the brachial arm, and central SBP and pulse pressures (PPs) were derived from radial artery pressure waveforms between the 26th and the 28th week of gestation. Pregnancy-associated hypertension (including gestational hypertension and preeclampsia) was ascertained from medical records. Plasma phosphatidylcholine n-3 and n-6 PUFAs were measured by gas chromatography and expressed as percentage of total fatty acids.Peripheral SBP was inversely associated with total n-3 PUFAs [-0.51 (95% confidence interval, CI, -0.89 to -0.13) mm Hg] and long-chain n-3 PUFAs [-0.52 (CI -0.92 to -0.13) mmHg]. Similar but weaker associations were observed for central SBP and PP. Dihomo-γ-linolenic acid was marginally positively associated with peripheral SBP, central SBP, and PP, whereas linoleic acid and total n-6 PUFAs showed no significant associations with blood pressures. We identified 28 pregnancy-associated hypertension cases, and 1% increase in total n-3 PUFAs was associated with a 24% lower odds of pregnancy-associated hypertension (odds ratio 0.76; 95% CI 0.60 to 0.97). Maternal ethnicity modified the PUFAs-blood pressure relations, with stronger inverse associations with n-3 PUFAs in Chinese women, and stronger positive associations with n-6 PUFAs in Indian women (P values for interaction ranged from 0.02 to 0.07).Higher n-3 PUFAs at midgestation are related to lower maternal blood pressures and pregnancy-associated hypertension in Asian women, and the ethnicity-related variation between PUFAs and blood pressures deserves further investigation.

Disparities in maternal hypertension and pregnancy outcomes: evidence from North Carolina, 1994-2003

OBJECTIVES

To better understand disparities in pregnancy outcomes, we analyzed data from North Carolina to determine how the pattern of maternal hypertensive disorders differs among non-Hispanic white (NHW), non-Hispanic black (NHB), and Hispanic women across the range of maternal ages. In addition, we explored whether rates of poor birth outcomes, including low birthweight (LBW) and preterm birth (PTB), among hypertensive women differed by race.

METHODS

We restricted our analyses to births occurring between 1994 and 2003, constructing six five-year maternal age categories: 15-19 years, 20-24 years, 25-29 years, 30-34 years, 35-39 years, and 40-44 years. We used logistic regression to determine the relative contribution of race and age to incidence of maternal hypertension. All analyses controlled for the standard covariates of maternal education, marital status, and tobacco use. To assess the impact of maternal hypertension on birth outcomes, we limited the dataset to women with any hypertensive disorder and used linear regression to determine how particular race-age combinations affected outcomes. We also used logistic regression to find out how particular race-age combinations affected the likelihood of LBW and PTB.

RESULTS

The risk of hypertension differed by race, with NHB women exhibiting the highest risk and Hispanic women the lowest risk. Further, rates of hypertension increased with age. Among hypertensive women, pregnancy outcomes differed by race and age, with NHB women having the poorest outcomes (i.e., LBW and PTB) and age exhibiting a dose-response relationship in PTB and very PTB.

CONCLUSIONS

Patterns of maternal hypertension and subsequent outcomes are important contributors to persistent disparities in pregnancy outcomes.

African-American women have a higher risk for developing peripartum cardiomyopathy

OBJECTIVES

The purpose of this study was to assess whether African-American women are at increased risk of having peripartum cardiomyopathy.

BACKGROUND

Peripartum cardiomyopathy is a heart disease of unknown cause that affects young women, often with devastating consequences. The frequency of peripartum cardiomyopathy varies markedly between African and non-African regions.

METHODS

A case-control study was performed at a regional center that provides medical care to a racially heterogeneous population. For each case, 3 healthy control patients were randomly selected who delivered babies within the same month.

RESULTS

African-American women had a 15.7-fold higher relative risk of peripartum cardiomyopathy than non-African Americans (odds ratio [OR]: 15.7, 95% confidence interval [CI]: 3.5 to 70.6). Other significant univariate risk factors were hypertension (OR: 10.8, 95% CI: 2.6 to 44.4), being unmarried (OR: 4.2, 95% CI: 1.4 to 12.3), and having had >2 previous pregnancies (OR: 2.9, 95% CI: 1.1 to 7.4). African-American ethnicity remained a significant risk factor for peripartum cardiomyopathy when other risk factors were considered in multivariable (OR: 31.5, 95% CI: 3.6 to 277.6) and stratified analyses (OR: 12.9 to 29.1, p < 0.001). Although the frequency of peripartum cardiomyopathy (185 of 100,000 deliveries) at this center was higher than in previous U.S. reports, it was comparable to the frequency in countries with more women of African descent (100 to 980 of 100,000). Analysis of other U.S. studies confirmed that the frequency of peripartum cardiomyopathy was significantly higher among African-American women.

CONCLUSIONS

African-American women have significantly higher odds of having peripartum cardiomyopathy that could not be explained by several other factors. Further research will be necessary to determine the potential environmental and/or genetic factors associated with African descent that confer this risk.

Poor outcome of indigent patients with peripartum cardiomyopathy in the United States

OBJECTIVE

Peripartum cardiomyopathy (PPCM) patients from Haiti and South Africa have poor survival and poor left ventricular (LV) function recovery compared with patients from the United States. There are no reported studies of PPCM among the African American population in the United States. We evaluated the prognosis of PPCM in a mostly African American population.

STUDY DESIGN

We analyzed the clinical and echocardiographic data of 44 (39 African American) patients with PPCM over an 11 year period (1992-2003).

RESULTS

Thirty-nine patients were indigent and 5 had health insurance. During a mean follow-up of 24.0 (range, 0.1-264) months, 7 (15.9%) patients died and LV function returned to normal in 14 (35%).

CONCLUSION

LV function recovery and survival rates of PPCM patients observed in our study are similar to those reported from Haiti and South Africa and different from what is generally accepted in the United States.

Is African descent an independent risk factor of peripartum cardiomyopathy?

Risk factors for peripartum cardiomyopathy (PPCM) are controversial. PPCM seems to be more prevalent in women of African descent, the highest observed incidence is in Haiti (1 per 300 live births). Our retrospective study conducted in Martinique showed an incidence of 1 per 5500 live births. This incidence is significantly lower than in Haiti. Women from Martinique and Haiti do not differ for most classical risk factors: African descent, age, pregnancy-associated hypertension, multiple pregnancy and pre-eclampsia. However, the parity rate and the socioeconomic level are different. Thus, African descent could be confounded by high parity rate and socioeconomic status.

Atherogenic lipoprotein phenotype and LDL size and subclasses in women with gestational diabetes

AIMS

Women with gestational diabetes are more likely to develop Type 2 diabetes and cardiovascular disease after pregnancy; however, the exact nature of the lipid alterations present is not clear. In Mediterranean women with gestational diabetes, we measured low-density lipoprotein (LDL) size and all seven subclasses, as well as the 'atherogenic-lipoprotein phenotype'[ALP, e.g. concomitant presence of elevated triglycerides, reduced high-density lipoprotein (HDL)-cholesterol and increased small, dense LDL].

METHODS

In 27 women with gestational diabetes and 23 healthy pregnant women matched for age, weeks of gestation and body mass index, we measured plasma lipids and LDL size and subclasses by gradient gel electrophoresis between 24 and 28 weeks of gestation.

RESULTS

Although no significant differences were found in the concentrations of any of the plasma lipids, compared with control subjects women with gestational diabetes had lower LDL size (P = 0.0007) due to reduced LDL-I (P = 0.0074) and increased LDL-IVA (P = 0.0146) and -IVB (P < 0.0001) subclasses. Correlation analysis revealed that fasting glucose, homeostasis model assessment and glycated haemoglobin were inversely correlated with LDL-I and positively with LDL-IVA and -IVB (all P < 0.05). ALP due to high HDL-cholesterol levels was not seen in either group, whereas elevated small, dense LDL were more common in women with gestational diabetes than control subjects (33% vs. 4%, P = 0.0107).

CONCLUSIONS

Increased levels of small, dense LDL are common in Mediterranean women with gestational diabetes. Whether these findings affect the atherogenic process and clinical end-points in these women remains to be determined by future prospective studies.

Hostility and anomie: links to preterm delivery subtypes and ambulatory blood pressure at mid-pregnancy

Underlying maternal vascular disease has been implicated as one of several pathways contributing to preterm delivery (PTD) and psychosocial factors such as hostility, anomie, effortful coping, and mastery may be associated with PTD by affecting maternal vascular health. Using data from the Pregnancy Outcomes and Community Health (POUCH) study, we included 2018 non-Hispanic White and 743 African American women from 52 clinics in five Michigan, USA communities. Women were interviewed at 15-27 weeks' gestation and followed to delivery. We found that relations between psychosocial factors and PTD subtypes (i.e. medically indicated, premature rupture of membranes, spontaneous labor) varied by race/ethnicity and socio-economic position (Medicaid insurance status). Among African American women not insured by Medicaid, anomie levels in mid-pregnancy were positively associated with medically indicated PTD after adjusting for maternal age and education. Among all women not insured by Medicaid, hostility levels were positively associated with spontaneous PTD after adjusting for maternal race/ethnicity, age, and education. Failure to detect links between psychosocial factors and PTD risk in poorer women may be due to their excess risk in multiple PTD pathways and/or a more complex web of contributing risk factors. In a subset of 395 women monitored for blood pressure, anomie scores were positively associated with systolic blood pressure and heart rate and hostility scores were positively associated with systolic and diastolic blood pressure, heart rate and mean arterial pressure in models that included time, awake/asleep, race/ethnicity, and age as covariates. Further adjustment for body mass index and smoking attenuated the anomie-vascular relations but had little effect on the hostility-vascular relations. Overall this study of pregnant women provides some physiologic evidence to support findings linking levels of anomie and hostility with risk of PTD.

Maternal hypertension as a risk factor for low birth weight infants: comparison of Haitian and African-American women

BACKGROUND

The rate of low birth weight (LBW) of Black women is more than twice that of White women. This study explores if the rate of LBW differs between Haitian and African-American women with chronic hypertension.

METHODS

A retrospective cohort study of all Black women self-identified as African-American (n = 12,258) or Haitian (n = 4320) delivering a singleton infant in Massachusetts between 1996 and 2000.

RESULTS

Haitian women were more likely than African-American women to have chronic hypertension (2.7% vs. 2.1%, p = 0.006), but had similar rates of preeclampsia (3.1% vs. 3.3%, p = 0.27). The LBW rate was 10% among African-American women and 8.2% among Haitian women. After adjustment for sociodemographic, medical, and prenatal care characteristics, the greatest risks for delivering a LBW infant for Haitian women were chronic hypertension (OR = 6.8; 95% CI, 4.3, 10.6) and preeclampsia (OR = 3.2; 95% CI, 2.0, 5.1). For African-American women, the greatest risks for LBW infants were a history of delivering a LBW infant (OR = 3.9; 95% CI, 2.8, 5.4) and chronic hypertension (OR = 2.9; 95% CI, 2.1, 4.0). In a combined logistic regression model including interaction terms, chronic hypertension and preeclampsia continued to be associated with the greatest risk of LBW among all women.

CONCLUSIONS

Differences in maternal risk factors and rates of LBW (8.2% vs. 10%) exist between Haitian and African-American women delivering infants in Massachusetts. While chronic hypertension and preeclampsia are strong risk factors for LBW for both Haitian and African-American women, unknown factors make these disorders much more potent for Haitian women.

Incidence and risk factors for stroke in pregnancy and the puerperium

OBJECTIVE

To estimate the incidence, mortality, and risk factors for pregnancy-related stroke in the United States.

METHODS

The Nationwide Inpatient Sample from the Healthcare Cost and Utilization Project of the Agency for Healthcare Research and Quality, for the years 2000-2001 was queried for International Classification of Diseases, 9th Revision, codes for stroke among all pregnancy-related discharges.

RESULTS

A total of 2,850 pregnancy-related discharges included a diagnosis of stroke for a rate of 34.2 per 100,000 deliveries. There were 117 deaths or 1.4 per 100,000 deliveries. Twenty-two percent of survivors were discharged to another facility. The risk of stroke increased with age, particularly ages 35 years and older. African-American women were at a higher risk, odds ratio (OR) 1.5 (95% confidence interval [CI] 1.2-1.9). Medical conditions that were strongly associated with stroke included migraine headache, OR 16.9 (CI 9.7-29.5), thrombophilia, OR 16.0 (CI 9.4-27.2), systemic lupus erythematosus, OR 15.2 (CI 7.4-31.2), heart disease, OR 13.2 (CI 10.2-17.0), sickle cell disease, OR 9.1 (CI 3.7-22.2), hypertension, OR 6.1(CI 4.5-8.1) and thrombocytopenia, OR 6.0 (CI 1.5-24.1). Complications of pregnancy that were significant risk factors were postpartum hemorrhage, OR 1.8 (CI 1.2-2.8), preeclampsia and gestational hypertension, OR 4.4 (CI 3.6-5.4), transfusion OR 10.3 (CI 7.1-15.1) and postpartum infection, OR 25.0 (CI 18.3-34.0).

CONCLUSION

The incidence, mortality and disability from pregnancy related-stroke are higher than previously reported. African-American women are at an increased risk, as are women aged 35 years and older. Risk factors, not previously reported, include lupus, blood transfusion, and migraine headaches. Specific strategies, not currently employed, may be required to reduce the devastation caused by stroke during pregnancy and the puerperium.

LEVEL OF EVIDENCE

II-2.

An assessment of pregnancy-related mortality in the United States

Deaths from pregnancy complications remain an important public health concern. Nationally, two systems collect information on the number of deaths and characteristics of the women who died from complications of pregnancy. The Centers for Disease Control and Prevention's (CDC) National Center for Health Statistics (NCHS) reports maternal mortality through the National Vital Statistics System (NVSS); CDC National Center for Chronic Disease Prevention and Health Promotion's Pregnancy Mortality Surveillance System (PMSS) conducts epidemiological surveillance of pregnancy-related deaths. The numbers of deaths reported by these two systems have differed over the past two decades; our objective was to determine the magnitude and nature of these differences. For 1995-97, we compared maternal deaths in the NVSS with pregnancy-related deaths in PMSS for the 50 States, Washington DC and New York City. Pregnancy-related deaths whose underlying cause was assigned to ICD-9 codes 630-676 by NVSS were classified as maternal deaths; those coded outside 630-676 were not. There were 1387 pregnancy-related deaths in PMSS and 898 maternal deaths in the NVSS; 54% of these deaths were reported in both systems, 40% in PMSS only, and 6% in NVSS only. Pregnancy-related deaths due to haemorrhage, embolism, and hypertensive complications of pregnancy were proportionately more often identified by NVSS as maternal deaths than those from cardiovascular complications, medical conditions or infection. From the 1471 unduplicated deaths classified as maternal or pregnancy-related from either reporting system, we estimated a combined pregnancy-related mortality ratio of 12.6/100,000 live births for 1995-97, compared with 11.9 for PMSS only and 7.5 for NVSS only. The identification and classification of these events is dependent on the provision of complete and accurate cause-of-death information on death certificates. Changes in the guidelines for coding maternal deaths under ICD-10 may change the relationship in the number of deaths resulting from pregnancy reported by these two systems.

Hypertension during pregnancy in South Australia, Part 2: Risk factors for adverse maternal and/or perinatal outcome - results of multivariable analysis

OBJECTIVE

To identify factors associated with adverse pregnancy outcomes among women with hypertension during pregnancy.

DESIGN

A population-based retrospective multivariable analysis using the South Australian perinatal data collection.

METHODS

Perinatal data on 70,386 singleton births in 1998-2001 were used in multivariable analyses on three groups: all women combined, all hypertensive women and women with pregnancy hypertension only, in order to identify independent risk factors for requirement for level II/III care, preterm birth, small for gestational age (SGA) birth and maternal length of stay greater than 7 days.

RESULTS

The risks for the four morbidities were all increased among women with hypertension compared with normotensive women. Those with pre-existing hypertension had the lowest risk (with odds ratios (OR) 1.26-2.90). Pregnancy hypertension held the intermediate position (OR 1.52-5.70), while superimposed pre-eclampsia was associated with the highest risk (OR 2.00-8.75). Among women with hypertension, Aboriginality, older maternal age, nulliparity and pre-existing or gestational diabetes increased the risk for level II/III nursery care, preterm birth and prolonged hospital stay. Smokers had shorter stays, which may be related to their decreased risk of having a Caesarean section or operative vaginal delivery. Asian women, Aboriginal women, smokers and unemployed women had an increased risk for having an SGA baby, while women with pre-existing or gestational diabetes had a reduced risk.

CONCLUSIONS

Among hypertensive pregnant women, nulliparity, older maternal age, Aboriginality, unemployment and diabetes are independent risk factors for one or more major adverse pregnancy outcomes. Smoking does not always worsen the outcome for hypertensive women except for SGA births.

[Dyspnoea in pregnant female immigrants due to unexpected mitral valve stenosis]

Three female patients, a 22-year-old Moroccan woman, a 25-year-old Turkish woman and a 35-year-old Iraqi woman, became increasingly dyspnoeic during their pregnancy; this was a symptom of congestive heart failure due to mitral valve stenosis. Since all patients were refractory to medical treatment, they underwent invasive therapy by percutaneous transvenous mitral balloon valvotomy (PTMV). In two patients this therapy was successful, but in one patient a closed mitral valvotomy was needed. All three women delivered healthy infants, two immediately following the PTMV; at follow-up 2-4 years later, the women and infants were all doing well. The prevalence of mitral valve stenosis in the western world is increasing because of changing immigration patterns. When pregnant patients start complaining about dyspnoea, especially if they are immigrants, one should be aware of the possibility of mitral valve stenosis. PTMV is a safe and successful treatment for these patients and is preferred above surgical therapy because of its low morbidity and mortality for both mother and foetus. PTMV must be performed in a thoracic surgery centre by an experienced team and the X-ray exposure should be minimised.

Differential risk of hypertensive disorders of pregnancy among Hispanic women

Preeclampsia and gestational hypertension are leading complications of pregnancy that also portend increased risk of future chronic hypertension. Although rates of chronic hypertension differ between non-Hispanic Caucasian and Hispanic women, few studies examined their relative rates of hypertensive disorders of pregnancy. The purpose of this study was to compare the risk of preeclampsia and gestational hypertension in a prospective cohort of normotensive, nulliparous Hispanic (n = 863) and non-Hispanic Caucasian women (n = 2,381). Compared with non-Hispanic Caucasian women, Hispanic women demonstrated a significantly decreased incidence of gestational hypertension (1.6% versus 8.5%; P < 0.01), but a similar incidence of preeclampsia (3.8% versus 3.7%; P = 0.9). Adjusting for age, smoking, diabetes, BP, body mass index (BMI), and multiple gestation uncovered an increased relative risk (RR) for preeclampsia among Hispanic women (RR 1.9; 95% CI, 1.1 to 3.3; P = 0.01), while their relative risk for gestational hypertension remained significantly decreased (RR 0.39; 95% CI, 0.22 to 0.72; P < 0.01). Among women who initially presented with hypertension during pregnancy, Hispanic women were over threefold (hazard ratio 3.3; 95% CI, 1.9 to 6.0; P < 0.01) more likely to develop preeclampsia than non-Hispanic Caucasian women. Besides Hispanic ethnicity, baseline BP, BMI, diabetes, and multiple gestation were independent risk factors for preeclampsia, whereas only baseline BP and BMI were associated with gestational hypertension. Socioeconomic status and access to prenatal care were not associated with either disorder. Hispanic ethnicity is independently associated with increased risk for preeclampsia and decreased risk for gestational hypertension. The initial presentation of hypertension during pregnancy in Hispanic women most likely represents early preeclampsia.

Epidemiology of preeclampsia in Mauritius island

In Mauritius, the maternal mortality rate (MMR) was 21 per 100000 live births for the year 2001 and this is comparable with figures from developed countries. There has been poor documentation in the area of hypertensive disorders of pregnancy until recently in the island. Consequently, we analysed data from the Ministry of Health. Hypertensive disorders of pregnancy occurred in 6.7% gravidas in 2001. Out of four maternal deaths recorded in 2001, two occurred due to severe eclampsia. In the second part of our study, we scrutinised also the obstetric notes and interviewed 862 hospitalised women from four main hospitals of the island between 1995 and 1997. The majority of women were affected by non-proteinuric hypertension (70%), followed by preeclampsia (24%) and chronic hypertension (6%). Preeclamptic primi and multigravidas developed the condition earlier and also gave birth to growth-retarded babies. Highly significant results supported the relationship between growth retardation and preeclampsia in different parities, irrespective of the length of exposure of the baby in utero. Preeclampsia affects both Indo-Mauritians and Creoles to the same extent, but the latter are much more prone to gestational hypertension. In addition, hypertensive disorders of pregnancy are more a problem of multigravid women in Creoles while they are more classically a condition of primigravidae in Indians.

Testing the weathering hypothesis among Mexican-origin women

OBJECTIVE

To examine the "weathering hypothesis," as proposed by Geronimus (1986; 1987; 1992; 1996), among US-born and foreign-born Mexican-origin women. This hypothesis specifically argues that the relationship between age and a variety of reproductively related heath outcomes varies by socioeconomic and environmental context.

METHODS

1989-1991 National Center for Health Statistics (NCHS) linked birth-death files. These files include all women who experienced a live birth in the United States and whose infants were issued a birth certificate during the years 1989 to 1991 (NCHS 1995). Age and nativity specific distributions on infant mortality, low birth weight, anemia, pregnancy related hypertension, and smoking were estimated for Mexican-origin women.

RESULTS

For the foreign-born, levels of neonatal mortality are highest for younger women and tend to increase again in women at the oldest ages. For the US born, the lowest levels are for women aged 17 and 18 years, and 27-29 years. Levels for women aged 19-24 years and 30-34 years are higher than those for 17-and 18-year-olds. For both groups of women, giving birth to infants with low birth weight is most common at the earlier ages, declining more or less until the mid twenties when the rate begins to rise again slowly. Patterns for the maternal health indicators vary, with pregnancy related hypertension most strongly following the pattern suggested by weathering.

CONCLUSION

Overall, this analysis suggests that there is evidence of weathering within the Mexican-origin population, particularly for the US-born population, and this is most clearly seen in levels of neonatal mortality and pregnancy related hypertension.

Mild gestational hypertension: differences in ethnicity are associated with altered outcomes in women who undergo outpatient treatment

OBJECTIVE

The purpose of this study was to evaluate the impact of ethnicity on outcome in women with mild gestational hypertension that is remote from term.

STUDY DESIGN

Nulliparous women with mild gestational hypertension who participated in an outpatient monitoring program between January 1995 and December 1999 were candidates. Patients had a singleton pregnancy at <37 weeks of gestation and were followed up for a minimum of 2 days as an outpatient. Maternal and perinatal outcomes were compared between groups by the Student t test, Mann-Whitney U test, and Pearson chi2 analyses.

RESULTS

One thousand one hundred eight-two women were included in the analysis. No clinically remarkable differences in gestational age or incidence of proteinuria at the start of observation were noted. Newborn infants of Hispanic and African American women had significantly smaller birth weights compared with those of white women. African American women had a higher incidence of abruptio placentae (n = 5), stillbirths (n = 3), and neonatal deaths (n = 2) versus the other groups (n = 0 for all). The frequency of progression to thrombocytopenia/HELLP (hemolysis, elevated liver enzymes, and low platelet count syndrome) and cesarean delivery rates were similar between groups.

CONCLUSION

Differences in outcomes are observed between ethnic groups even when the women undergo the same intensive outpatient monitoring for mild gestational hypertension.

Preeclampsia associated with chronic hypertension among African-American and White women

OBJECTIVE

To examine the racial differences in preeclampsia/eclampsia (preeclampsia) associated with chronic hypertension among African-American and White women.

METHODS

Using hospital discharge summary records from the National Hospital Discharge Survey from 1988 to 1996, we conducted a case-control study to assess the risk of preeclampsia among women with chronic hypertension in two separate identical models: one for African-American and another for White women. Cases were pregnant women who developed preeclampsia. Controls were women without preeclampsia. The main exposure was chronic hypertension. Logistic regression was used to derive odds ratios (OR) and 95% confidence intervals (CI) and to assess interaction between hypertension and preeclampsia. Population attributable risk percent associated between chronic hypertension and preeclampsia was calculated for each ethnic group.

RESULTS

Preeclampsia was more than eleven times likely among women with chronic hypertension compared to normotensive women for both African-American (OR = 12.4, 95% CI = 10.2-15.2) and White women (OR = 11.3, 95% CI = 9.7-13.2). Among African-American women, we found an interaction between chronic hypertension and region on preeclampsia. The effect of region magnified the risk of preeclampsia associated with chronic hypertension in general for African-American women, but the effect was lower for the Southern region (OR = 8.9, 95% CI = 6.4-12.3). We also found that the point estimate of population attributable risk percent of preeclampsia attributable to chronic hypertension was significantly higher for African-American women (10.3, 95% CI = 8.6-12.5) compared to White women (5.3, 95% CI = 4.7-6.4).

CONCLUSION

The more than eleven-fold higher risk of preeclampsia among both African-American and White women with chronic hypertension compared to normotensive women underscores the potential risk of chronic hypertension for adverse pregnancy outcomes. Furthermore, the two-fold higher population attributable risk percent of preeclampsia among African-American compared to White women quantifies the burden of preeclampsia attributable to chronic hypertension, and indicates a greater opportunity for prevention.

Venous thromboembolism in pregnant Chinese women

OBJECTIVE

To evaluate the incidence, disease pattern, and risk factors for thromboembolism in pregnant Chinese women.

METHODS

We conducted a study from January 1998 to December 2000. Women with thromboembolic diseases were identified and their case records retrieved and reviewed. Demographic characteristics were compared between women with and without thromboembolism.

RESULTS

Thirty-two women were diagnosed as having thromboembolic disease during the study period. The total number of deliveries over the study period was 16,993, giving an incidence of 1.88 per 1000 deliveries. There were two cases of pulmonary embolism and one resulted in a maternal death. The others had deep vein thrombosis of which over 80% were limited to calf veins only. The ultrasound examinations requested for suspected deep venous thrombosis before and after the event of maternal death were 1.62 and 10.7 per 1000 deliveries (P <.001); and the corresponding cases of deep venous thrombosis diagnosed were 0.29 and 2.94 per 1000 deliveries, respectively (P <.001). The majority (75%) of cases were diagnosed in the postpartum period, mainly after cesarean delivery. Women with venous thromboembolism were older, had higher body mass index, and a higher incidence of preeclampsia.

CONCLUSION

Thromboembolic disease is not uncommon among pregnant Chinese women. The incidence was similar to that of the white population, although the sites of vascular occlusion were different. The long-standing belief that thromboembolism is rare among Chinese is at least partly because of underdiagnosis.

The influence of maternal hypertension on low birth weight: differences among ethnic populations

OBJECTIVE

To determine the influence of maternal hypertension on the risk of low birth weight among white, black, and Hispanic residents of New York City.

METHODS

New York City birth certificates, 1988 through 1994, provided data on maternal and infant characteristics. Hypertension was self-reported on birth certificates, and was categorized as chronic or pregnancy-related hypertension. The complication of preeclampsia/eclampsia was also noted. The risk of low birth weight (<2500 grams) for maternal hypertension was determined.

RESULTS

The prevalence of hypertension during pregnancy was 3.8% overall, and was highest for blacks and lowest for whites. Low birth weight rates for white, black, and Hispanic babies were 5.0%, 12.8%, and 7.5%, respectively. Low birth weight rates among hypertensive mothers for whites, blacks and Hispanics were 16.8%, 24.4% and 19.5% respectively. The trends were similar for chronic and pregnancy-related hypertension, as well as for preeclampsia/eclampsia. The relative risk of low birth weight offspring among all hypertensive mothers was highest among whites (3.58, 95% CI = 3.39-3.79), and lowest among blacks (1.99, 95% CI = 1.93-2.06). This trend persisted for chronic and pregnancy-related hypertensive mothers, and those with preeclampsia/eclampsia, after adjusting for other maternal socioeconomic characteristics. Due to the higher prevalence of hypertension among black mothers, the population attributable risk of low birth weight was highest among black babies (557 per 100,000 live births) and lowest among whites (309 per 100,000 live births).

CONCLUSION

Maternal hypertension is an important risk factor for low birth weight. Its impact, however, differed by race/ethnicity groups.

Is angiotensinogen gene polymorphism associated with hypertension in pregnancy?

OBJECTIVE

To determine whether a state of hypertension in pregnancy in the Japanese can be predicted in the early period based on detection of the M235T variant of the angiotensinogen gene, alone or with other factors.

METHODS

A total of 313 Japanese pregnant women were divided into 3 groups on the basis of their angiotensinogen genotype: TT, MT, and MM. Hypertension in pregnancy was diagnosed for 33 patients in all. For each group, we sought to determine what factors increased the risk of the disease.

MAIN OUTCOME MEASURES

The angiotensinogen M235T variant, mean arterial pressure (MAP) before the 12th gestational week, body mass index (BMI) before pregnancy, age at delivery, parity, a familial history of hypertension, and development of preeclampsia or gestational hypertension were considered.

RESULTS

The frequencies of the allele T were the same among preeclampsia, gestational hypertension, and normal subjects. In TT subjects, a high incidence of gestational hypertension was found for women with MAP > or = 90 mm Hg, high or low BMI before pregnancy > or = 22.0 or < 18.0, and maternal history of hypertension. In MT subjects, women who showed MAP > or = 90 mm Hg or who were above 36 years old at delivery had a high incidence of gestational hypertension. Preeclampsia could not be predicted in either group.

CONCLUSIONS

Hypertension in pregnancy cannot be predicted on the basis of the M235T variant of angiotensinogen gene alone. However, gestational hypertension is associated with combinations of other factors. In contrast, it is virtually impossible to predict the development of preeclampsia.

Blood lead level and blood pressure during pregnancy in South Central Los Angeles

In many studies in which the relationship between blood pressure and blood lead level has been examined, investigators have found significant--but small--associations. There was only one previous report of a significant association of blood lead with blood pressure in pregnant women. We measured blood lead level and sitting blood pressure of 1,627 women in their third trimester of pregnancy. We eliminated subjects with known causes of hypertension. Most women (98.4%) were normotensive. We controlled for body mass index, age, and stress--among other factors--and constructed multiple-regression models of lead association with diastolic and systolic blood pressures. Immigrants (73% of total) had significantly higher blood lead levels and different blood pressures than nonimmigrants, suggesting that analysis be stratified by "immigrant, nonimmigrant" status. Positive relationships between blood lead level and blood pressure were found only for immigrants (p < or = .001). From the 5th to 95th blood-lead percentiles (0.9-6.2 microg/dl) in immigrants, systolic blood pressure increased 2.8 mm Hg, and diastolic blood pressure increased 2.4 mm Hg. Higher prior lead exposure of immigrants (97.7% from Latin countries) than nonimmigrants might explain the differential effect of these low levels of blood lead on blood pressure in nonimmigrants. Perhaps some immigrants are at higher risk than nonimmigrants for lead-associated elevated blood pressure during pregnancy, despite blood lead levels within the currently considered acceptable range.

Obstetric and neonatal outcome following chronic hypertension in pregnancy among different ethnic groups

We retrospectively studied pre-eclampsia rate and obstetric outcome in a cohort of 436 pregnancies amongst 318 women of different ethnic backgrounds attending an antenatal hypertension clinic from 1980-1997, identifying 152 women (213 pregnancies) with chronic essential hypertension. The ethnic breakdown was: White, 64 (30.0%) pregnancies in 48 (31.5%) women; Black/Afro-Caribbean, 79 (37.1%) pregnancies in 56 (36.8%) women; and Indo-Asians, 70 (32.3%) pregnancies in 48 (31.6%) women. The prevalences of pre-eclampsia in White, Black and Indo-Asian women were 17.2%, 12.7% and 18.6%, respectively (p = 0.58). Pregnancies of Indo-Asian women were of shorter gestation, and babies in this group also had lower birth weight and ponderal index compared to those of White and Black women (all p < 0.05). The proportions of overall perinatal mortality were 1.6% for Whites (1/64), 3.8% for Blacks (3/79) and 10.0% for Indo-Asians (7/70), suggesting increased risk in the Indo-Asian group. Indo-Asian women with chronic essential hypertension need careful antenatal care and observation during pregnancy.

Maternal hypertension and spontaneous preterm births among black women

OBJECTIVE

To examine effects of maternal hypertension on spontaneous preterm birth (birth at less than 37 weeks' gestation) among black women.

METHODS

Using hospital discharge summary records from the National Hospital Discharge Survey between 1988 and 1993, we conducted a case-control study to assess the risk of spontaneous preterm birth among black women with chronic hypertension preceding pregnancy and pregnancy-induced hypertension. Logistic regression was used to derive odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

Preterm births were almost two times more likely for women with pregnancy-induced hypertension (OR = 1.8; 95% CI, 1.5, 2.2), more than 1.5 times more likely for women with chronic hypertension preceding pregnancy (OR = 1.6; 95% CI, 1.3, 2.1), and more than four times more likely for women with pregnancy-aggravated hypertension (OR = 4.4; 95% CI, 2.9, 6.7) compared with normotensive women. Preterm births also were associated significantly with antepartum hemorrhage, poor fetal growth, marital status, and source of payment. The odds of preterm birth by maternal hypertension were increased among women with chronic hypertension and genitourinary infection, whereas the odds of preterm birth were reduced among women with pregnancy-induced hypertension and genitourinary infection.

CONCLUSION

These findings are important in demonstrating the relation between type of hypertension in pregnancy and preterm birth. The relationships between maternal hypertension and preterm birth need to be further investigated to provide some guidelines in the management of hypertension in pregnancy and assessment of prenatal care compliance for black women, particularly when genitourinary infection is present.

The effect of ethnicity on the development of small for gestational age infants associated with hypertension in pregnancy

The objective of this article is to assess in a hypertensive pregnant population the role of ethnic background on the development of small for gestational age (SGA) infants. A cohort population of 366 pregnant women who developed new hypertension in their pregnancy were interviewed and their ethnic groups defined. We then compared the outcomes of the pregnancies with regard to the development of SGA infants among the various ethnic groups. Preeclamptic women were more likely to deliver a SGA infant than gestational hypertensive women. Women of East Indian descent delivered the highest incidence of SGA infants when they developed preeclampsia (50%) compared to an incidence in the White population of 13.8%. Only the ethnocultural group, mean third-trimester blood pressure and third-trimester hematocrit, significantly correlated with the development of a SGA infant. Chinese and East Indian women who develop preeclampsia are at the highest risk of having a growth-restricted infant.

Racial differences in outcome of pregnancies complicated by hypertension

Racial differences in the outcome of pregnancies complicated by hypertension (HTN) were examined using data obtained from a large perinatal data base with 109,428 consecutive deliveries from 1982 to 1987. Black women had a higher prevalence of hypertension than white women (prevalence ratio 2.3, 95% CI 2.2, 2.5). However, when compared to normotensive women of similar race, white hypertensive women showed a higher risk for adverse pregnancy outcome than black hypertensives as indicated by the higher odds ratio for prematurity (OR: 1.7 for white [W], 1.2 for black [B]), low birth weight (OR: 2.4 W; 1.5 B), intrauterine growth retardation (OR: 4.4 W; 1.6 B) and perinatal death (OR 2.3 W; 1.2 B). Hypertension was associated with a 156 g reduction in birthweight of newborns in whites as compared to a 63 g reduction in blacks. Further studies are needed to understand the racial differences in the impact of HTN on pregnancy outcome.

Does advanced maternal age affect pregnancy outcome in women with mild hypertension remote from term?

OBJECTIVES

Our purpose was to compare maternal and perinatal outcomes of mature women with those in younger women with pregnancies complicated by mild hypertension remote from term.

STUDY DESIGN

A matched cohort design was used. A total of 379 mature pregnant women (> or = 35 years old) with mild hypertension remote from term were matched for race, gestational age, and proteinuria status at enrollment with 379 adult controls aged 20 to 30 years also with mild hypertension remote from term. All were enrolled in an outpatient management program that included automated blood pressure measurements and daily assessment of weight, proteinuria, and fetal movement.

RESULTS

The mean gestational age at enrollment was 32.7 +/- 3.0 weeks for both groups (range 24 to 36 weeks). By matching 20.6% of patients in each group had > or = 1+ proteinuria on urinary dipstick at enrollment, and 77.3% of patients in each group were white. Chronic hypertension was more common in the mature group (22.4% vs 14.5%, p = 0.007). The mean gestational age at delivery (37.2 +/- 2.3 vs 37.2 +/- 2.2 weeks), the mean pregnancy prolongation (28.1 +/- 21.0 vs 28.4 +/- 22.0 days), and the mean birth weights (2864 +/- 770 vs 2906 +/- 788 gm) were similar between the mature and younger groups (all p > 0.05). There were no differences regarding abruptio placentae (2 vs 3 cases) or thrombocytopenia or HELLP (hemolysis, elevated liver enzymes, low platelets) syndrome (7 vs 9 cases), and there were no cases of eclampsia. There were five stillbirths in the mature group and none in the younger group (p = 0.063).

CONCLUSION

Outpatient management of mild hypertension remote from term in the mature pregnant women was associated with similar maternal outcomes but with a nonstatistically higher stillbirth rate compared with the younger pregnant woman.

Preeclampsia and neonatal outcomes in chronic hypertension: comparison between white and black women

We compared the incidence of preeclampsia and neonatal outcomes in 208 white (born in Canada) and 74 black (born in Haiti) women with mild chronic hypertension. Controls included 17,677 white and 2,400 black normotensive women delivered in the same center between 1987 and 1991. Superimposed preeclampsia (32.4% vs 14.9%; p < 0.01), perinatal mortality (9.5% vs 2.9%; p < 0.05) and prematurity (32.4% vs 19.7%; p < 0.05) were more frequent in black than in white women with chronic hypertension. Within both races, chronic hypertensive women with superimposed preeclampsia demonstrated higher rates of perinatal mortality and morbidity than controls. White chronic hypertensive women without preeclampsia and controls had similar rates of perinatal mortality as compared to black study participants and controls (2.3% vs 1.4%), small-for-gestational-age newborns (10.7% vs 7.8%) and prematurity (12.4% vs 15.3%). Compared to black controls, black chronic hypertensive women without preeclampsia had higher rates of perinatal mortality (1.2% vs 8.0%; p < 0.001) and prematurity (9.0% vs 18.0%; p < 0.05). These data provide evidence of ethnic differences in perinatal outcomes in chronic hypertensive women that are not explained only by superimposed preeclampsia.

Hypertensive disorders of pregnancy in southwestern Navajo Indians

BACKGROUND

The Navajos are the largest Native American tribe. They, like other Native Americans, appear to be in an "epidemiologic transition" and are accordingly experiencing increased rates of hypertension, diabetes, and obesity.

METHODS

A retrospective chart review of all pregnancies in 1991 at the Crownpoint Indian Health Service Facility in Crownpoint, NM, was conducted to determine the prevalence of hypertensive disorders of pregnancy in this Navajo population.

RESULTS

Seventy-five (12.6%) of 594 pregnancies were associated with a hypertensive disorder. There were 18 individuals who developed gestational hypertension and 10 individuals with chronic hypertension that persisted during pregnancy. There were 46 women (7.7%) who developed preeclampsia and one woman (0.3%) who developed eclampsia. Eight women (1.4%) with chronic hypertension developed superimposed preeclampsia during pregnancy. Thus, 12.3% of these pregnancies in Navajo women were associated with the development of, or worsening, hypertension, and there was a prevalence of preeclampsia of 9.1%.

CONCLUSION

The Navajos exhibit a high prevalence of pregnancy-related hypertension and preeclampsia.

The risk of pregnancy-induced hypertension: black and white differences in a military population

The relationship between race and risk of pregnancy-induced hypertension was investigated in a cohort of active-duty military women who gave birth during the period 1987 through 1989. Cases were identified through hospital discharge diagnoses and included transient gestational hypertension, pre-eclampsia, eclampsia, and unspecified hypertension complicating pregnancy. Multivariate analysis showed nulliparous Black women to be at a slightly increased risk for all pregnancy-induced hypertension (risk ratio [RR] = 1.2) and for pre-eclampsia (RR = 1.3) compared with nulliparous White women. Black parous women were found to have a slightly reduced risk of all pregnancy-induced hypertension (RR = 0.77) and pre-eclampsia (RR = 0.38) compared with White parous women.

Selected antepartum medical complications and very-low-birthweight infants among black and white women

This study estimated the risk of very-low-birthweight delivery among Black and White women with selected treatable antepartum medical conditions. A logistic regression model was applied to a retrospective, population-based data set identified by computerized, linked birth certificate and maternal hospital discharge records. For Black mothers, the adjusted odds ratio for very-low-birthweight delivery was statistically significant for essential hypertension and urinary tract infection. For White mothers, the adjusted odds ratio was statistically significant for essential hypertension, urinary tract infection, pregnancy-induced hypertension, and diabetes mellitus. Public policy designed to reduce the risk of very-low-birthweight delivery must include strategies for attenuating the impact of treatable antepartum medical conditions.

Chronic hypertension, pregnancy-induced hypertension, and low birthweight

We examined the associations between chronic hypertension, pregnancy-induced hypertension, and low birthweight in a retrospective cohort study using Washington birth certificate data. The adjusted prevalence ratio for low birthweight associated with chronic hypertension was 3.9 [95% confidence interval (CI) = 3.4-4.4]. The prevalence ratio for pregnancy-induced hypertension associated with chronic hypertension ranged from 3.6 (95% CI = 3.2-4.1) for primiparous women to 10.7 (95% CI = 8.7-13.2) for multiparous women. The association of chronic hypertension and low birthweight could not be explained by the increased risk of pregnancy-induced hypertension in these women.

Blood pressure during pregnancy in Canadian Inuit: community differences related to diet

OBJECTIVE

To assess a possible relation between the incidence of hypertension during pregnancy and the consumption of fatty acids found in fish and sea mammals.

DESIGN

Retrospective survey of pregnancy-induced hypertension; prospective diet survey.

SETTING

Inuit women from seven communities in the Keewatin region of the Northwest Territories.

PATIENTS

All women from Arviat (formerly Eskimo Point), Baker Lake, Chesterfield Inlet, Coral Harbour, Repulse Bay, Sanikiluaq and Whale Cove who gave birth between Sept. 1, 1984, and Aug. 31, 1987.

MAIN OUTCOME MEASURES

All blood pressure measurements recorded during the pregnancy, incidence of pregnancy-induced hypertension in the seven communities, harvest of country food (food obtained from the land or sea rather than bought in a store) for six of the communities, self-reported consumption of fish, sea mammals and terrestrial mammals by a subgroup of the subjects and levels of phospholipid fatty acids in cord serum samples from a subgroup of the infants.

MAIN RESULTS

Significantly lower mean diastolic blood pressure values during the last 6 hours of pregnancy were noted for the women from the three communities with a higher consumption of fish and sea mammals (78.2 [95% confidence limits (CL) 76.6 and 79.9] mm Hg) than for those from the four communities with a lower consumption of such food (81.5 [95% CL 80.1 and 82.9] mm Hg) (p less than 0.005). The relation between community diet type and blood pressure was independent of other factors. Correspondingly, the women from communities with a lower consumption of marine food were 2.6 times more likely to be hypertensive during the pregnancy than those from communities with a higher consumption of marine food (p less than 0.007). Parity (p less than 0.05) and prepregnancy weight (p less than 0.005) were also significantly associated with pregnancy-induced hypertension; however, the relation between hypertension and community diet type remained significant in logistic regression analysis (odds ratio 2.56, p = 0.03). The differences between the community groups were substantiated by the results of the diet survey, the levels of eicosapentaenoic acid (EPA) in the cord serum phospholipids and the harvest data.

CONCLUSIONS

Increased consumption of fish may be beneficial for women at risk for hypertension during pregnancy. A prospective randomized trial of fish or EPA supplementation during pregnancy is warranted.

Dietary omega 3 fatty acids and gestational hypertension in the Inuit

Blood pressure at the end of pregnancy and the incidence of pregnancy-induced hypertension were monitored in Inuit communities in the Keewatin region of the Northwest Territories. Communities with more fish and sea mammals in their diet had a lower blood pressure at the end of pregnancy and a lower incidence of gestational hypertension. The lower incidence of gestational hypertension was independent of other variables, including pregravida weight and parity. Cord blood phospholipid fatty acid analysis confirmed higher levels of eicosapentanoic acid, a fatty acid enriched in fish and sea mammals, in infants born to mothers from communities with higher fish in their diets.

Sodium transport inhibitors in pregnancy-induced hypertension

In blacks and whites of similar socioeconomic background, the incidence of pregnancy-induced hypertension (PIH) is probably the same. In underdeveloped countries, however. PIH is often a life-threatening complication of pregnancy. Recent theories as to the etiology of PIH include the suggestion that vascular tone may be increased as a result of inhibition of active sodium transport in vascular smooth muscle. This may be the result of an inhibitor of sodium transport present in the serum. The literature concerning the demonstration of endogenous sodium transport inhibitors and endogenous digoxinlike immunoreactivity (EDLI) in PIH is reviewed and discussed.