Risk factors and outcome of failure to progress during the first stage of labor: a population-based study

BACKGROUND: One of the major indications for Cesarean section (CS) is failure of labor to progress. This study was aimed at defining obstetric risk factors for failure of labor to progress during the first stage, and to determine pregnancy outcome. METHODS: A population-based study comparing all singleton, vertex, term deliveries between the years 1988 and 1999 with an unscarred uterus, complicated with failure of labor to progress during the first stage with deliveries without non-progressive labor (NPL). Multiple logistic regression analysis was performed to investigate independent obstetric risk factors associated with failure of labor to progress during the first stage. RESULTS: Failure to progress during the first stage of labor complicated 1.3% (n = 1197) of all deliveries included in the study (n = 92 918), and resulted in CS. Independent risk factors for failure of labor to progress during the first stage, using a multivariable analysis, were premature rupture of membranes (PROM; OR = 3.8, 95% CI 3.2-4.5), nulliparity (OR = 3.8, 95% CI 3.3-4.3), labor induction (OR = 3.3, 95% CI 2.9-3.7), maternal age > 35 years (OR = 3.0, 95% CI 2.6-3.6), birth weight > 4 kg (OR = 2.2, 95% CI 1.8-2.7), hypertensive disorders (OR = 2.1, 95% CI 1.8-2.6), hydramnios (OR = 1.9, 95% CI 1.5-2.3), fertility treatment (OR = 1.8, 95% CI 1.4-2.4), epidural analgesia (OR = 1.6, 95% CI 1.4-1.8) and gestational diabetes (OR = 1.4, 95% CI 1.1-1.7). Although newborns delivered after failure of labor to progress during the first stage had significantly higher rates of Apgar scores lower than 7 at 1 and 5 min as compared with the controls (18.2% vs. 2.1%; P < 0.001 and 1.3% vs. 0.2%; P < 0.001, respectively), no significant differences were noted between the groups regarding perinatal mortality (0.3% vs. 0.4%; P = O.329). Maternal anemia and accordingly packed cells transfusion (47.4% vs. 22.8%; P < 0.001 and 5.6% vs. 1.0%; P < 0.001, respectively) were higher among pregnancies complicated with failure of labor to progress during the first stage as compared with the controls. CONCLUSIONS: Major risk factors for failure of labor to progress during the first stage were PROM, nulliparity, induction of labor and older maternal age. Indications for labor induction should be carefully evaluated in order to decrease the rate of operative deliveries.     

Gender does matter in perinatal medicine

OBJECTIVE: To investigate complications and outcome of pregnancies with male and female fetuses. METHODS: A population-based study comparing all singleton deliveries between the years 1988 and 1999 was performed. We compared pregnancies with male vs. female fetuses. Patients with a previous cesarean section (CS) were excluded from the study. Statistical analyses with the Mantel-Haenszel technique and multiple logistic regression models were performed to control for confounders. RESULTS: During the study period there were 55,891 deliveries of male and 53,104 deliveries of female neonates. Patients carrying male fetuses had higher rates of gestational diabetes mellitus (OR = 1.1; 95% CI 1.01-1.12; p = 0.012), fetal macrosomia (OR = 2.0; 95% CI 1.8-2.1; p < 0.001), failure to progress during the first and second stages of labor (OR = 1.2; 95% CI 1.1-1.3; p < 0.001 and OR = 1.4; 95% CI 1.3-1.5; p < 0.001, respectively), cord prolapse (OR = 1.3; 95% CI 1.1-1.6; p = 0.014), nuchal cord (OR = 1.2; 95% CI 1.1-1.2; p < 0.001) and true umbilical cord knots (OR = 1.5; 95% CI 1.3-1.7; p < 0.001). Higher rates of CS were found among male compared with female neonates (8.7 vs. 7.9%; OR = 1.1; 95% CI 1.06-1.16; p < 0.001). Using three multivariate logistic regression models and controlling for birth weight and gestational age, male gender was significantly associated with non-reassuring fetal heart rate patterns (OR = 1.5; 95% CI 1.4-1.6; p < 0.001), low Apgar scores at 5 min (OR = 1.5; 95% CI 1.3-1.8; p < 0.001) and CS (OR = 1.2; 95%CI 1.2-1.3; p < 0.001). Controlling for possible confounders like gestational diabetes, cord prolapse, failed induction, nonprogressive labor, fetal macrosomia, nuchal cord and true umbilical cord knots using the Mantel-Haenszel technique did not change the significant association between male gender and CS. CONCLUSION: Male gender is an independent risk factor for adverse pregnancy outcome.     

Maternal complications in women with chronic hypertension: a population-based cohort study

BACKGROUND: The aim of the study was to determine if pregnant women with chronic hypertensive disease have an independent risk for preeclampsia, gestational diabetes or placental abruption. To examine if superimposed preeclampsia in this group of women is related to an increased risk of placental abruption. METHODS: This study is a population-based cohort study using the Swedish Medical Birth Register 1992-98. A population of 681 515 women aged between 15-44 years with singleton pregnancies, excluding women with systemic lupus erythematosus (SLE), diabetes mellitus and chronic renal disease were studied. Among these, 3374 women were diagnosed with chronic hypertensive disease. Multiple logistic regression analysis was performed and the outcome measures of crude and adjusted odds ratios (OR) were presented with 95% confidence intervals (CI). RESULTS: Chronic hypertensive disease is associated with multiparity, age, high body mass index and Nordic ethnicity. After controlling for confounders, chronic hypertensive disease is an independent risk factor for preeclampsia (OR 3.8; 95% CI 3.4-4.3), gestational diabetes (OR 1.8; 95% CI 1.4-2.4) and placental abruption (OR 2.3; 95% CI 1.6-3.4). CONCLUSION: Chronic hypertensive disease is independently associated with an increased incidence of preeclampsia, gestational diabetes and placental abruption.     

Obstetric characteristics and perinatal outcome of pregnancies with uterine leiomyomas

OBJECTIVE: To determine the rate, obstetric characteristics and perinatal outcome of pregnancies with uterine leiomyomas. STUDY DESIGN: A population-based study comparing all singleton deliveries between the years 1988 and 1999 in women with and without uterine leiomyomas was performed. Patients lacking prenatal care were excluded from the analysis. Multivariable analysis, adjusting for possible confounders, such as maternal age, parity and gestational age, was performed to investigate associations between uterine leiomyomas and selected outcomes. RESULTS: There were 105,909 singleton deliveries with 690 (0.65%) complicated by uterine leiomyomas during the study period. Using a multivariable analysis, the following conditions were significantly associated with uterine leiomyomas: nulliparity (odds ratio [OR]=4.0, 95% confidence interval [CI] 3.3-4.7, P<.001), chronic hypertension (OR=1.9, 95% CI 1.6-2.4, P<.001), hydramnios (OR=1.5, 95% CI 1.2-2.0, P<.001), diabetes mellitus (OR=1.4, 95% CI 1.1-1.7, P=.001) and advanced maternal age (OR=1.2, 95% CI 1.1-1.2, P<.001). Higher rates of perinatal mortality (2.2% vs. 1.2%, OR=1.8, 95% CI 1.1-3.2, P<.001) were found in the uterine leiomyoma group as compared to the control group. While adjusting for maternal age, parity, gestational age and malpresentation, pregnancies with uterine leiomyomas had higher rates of cesarean deliveries (OR=6.7, 95% CI 5.5-8.1, P<.001), placental abruption (OR=2.6, 95% CI 1.6-4.2, P<.001) and preterm deliveries (<36 weeks' gestation, OR=1.4, 95% CI 1.1-1.7, P=.009) as compared to pregnancies without uterine leiomyomas. Conversely, no significant differences were noted regarding perinatal mortality (OR=1.4, 95% CI 0.7-2.8, P=.351) after controlling for maternal age, parity and gestational age using a multivariable analysis. CONCLUSION: Uterine leiomyomas increase the risk of adverse pregnancy outcomes, thus emphasizing the importance of appropriate intrapartum management of these high-risk pregnancies.     

Chronic hypertension as a risk factor for offspring to be born small for gestational age

BACKGROUND: Chronic hypertension during pregnancy is associated with an increased risk for birth of small for gestational age offspring. The aim of this study was to determine whether the risk remains after consideration of maternal characteristics and superimposed pre-eclampsia. METHOD: A population-based cohort study based on the Swedish Medical Birth Register 1992-98 and comprising 560 188 women aged 15-44 years with singleton pregnancies including 2,754 women with chronic hypertension. The register contains data of maternal characteristics besides maternal and fetal complications. Multiple logistic regression analysis was used. Small for gestational age was defined as birth weight less than -2SD adjusted for gestational age and sex. RESULTS: Chronic hypertensive women have an independent risk for small for gestational age (OR 3.1; 95% CI 2.7-3.7) when controlling for confounding of maternal characteristics such as age, parity, BMI, smoking, and ethnic origin. After introducing superimposed pre-eclampsia in the model the risk remains but decreases (OR 2.4; 95% CI 2.1-2.9). CONCLUSION: Chronic hypertension is an independent risk factor for birth of small for gestational age offspring. Pre-eclampsia is a strong mediating factor.     

Moderate to severe thrombocytopenia during pregnancy

OBJECTIVE: The objective was to investigate obstetric risk factors, complications, and outcomes of pregnancies complicated by moderate to severe thrombocytopenia. MATERIALS AND METHODS: A retrospective case-control study comparing 199 pregnant women with moderate to severe thrombocytopenia (platelet count below 100x10(9)/l) with 201 pregnant women without thrombocytopenia, who delivered between January 2003 to April 2004. Stratified analysis, using the Mantel-Haenszel procedure was performed in order to control for confounders. RESULTS: The main causes of thrombocytopenia were gestational thrombocytopenia (GT) (59.3%), immune thrombocytopenic purpura (ITP) (11.05%), preeclampsia (10.05%), and HELLP (Hemolysis, elevated liver enzymes and low platelet count) syndrome (12.06%). Women with thrombocytopenia were significantly older (30.7+/-5.9 versus 28.7+/-5.7; p=0.001) compared with patients without thrombocytopenia, and had higher rates of labor induction (OR=4.0, 95% CI=2.2-7.6, p<0.001) and preterm deliveries (OR=3.5, 95% CI=1.9-6.5, p<0.001). Even after controlling for labor induction, using the Mantel-Haenszel technique, thrombocytopenia was significantly associated with preterm delivery (weighted OR=3.14, 95% CI=1.7-6.0, p<0.001). Higher rates of placental abruption were found in pregnant women with thrombocytopenia (OR=6.2, 95% CI=1.7-33.2, p=0.001). In a comparison of perinatal outcomes, higher rates of Apgar scores <7 at 5 min were noted in infants of mothers with thrombocytopenia (OR=6.3, 95% CI=1.8-33.8, p=0.001), intrauterine growth restriction (IUGR; OR=4.6, 95% CI=1.5-19.1, p=0.003), and stillbirth (65/1000 versus 0 p<0.001). These adverse perinatal outcomes were found in rare causes of thrombocytopenia such as disseminated intravascular coagulation (DIC), familial thrombotic thrombocytopenic purpura (TTP), anti-phospholipid antibodies (APLA) syndrome, and myeloproliferative disease, and not among patients with GT. CONCLUSIONS: Moderate to severe maternal thrombocytopenia points to a higher degree of severity of the primary disease, which increases perinatal complications. However, the adverse outcome is specifically attributed to preeclampsia, HELLP syndrome, and rare causes, while the perinatal outcome of GT and ITP is basically favorable. Special attention should be given to patients with thrombocytopenia due to preeclampsia, HELLP syndrome, and rarer causes during pregnancy.     

Incidence of superimposed preeclampsia among pregnant Asian women with chronic hypertension

Objective: To determine the incidence and associated factors of superimposed preeclampsia among pregnant women with chronic hypertension.

Methods: A total of 300 pregnant women diagnosed with chronic hypertension were reviewed. Data were retrieved from medical records, including obstetric data, characteristics of hypertension, and pregnancy outcomes. Incidence of superimposed preeclampsia was estimated. Various characteristics were compared to determine associated risk factors.

Results: Mean age of the cohort was 34.3 years, 47% were nulliparous, 50% had hypertension before pregnancy, and the others presented with hypertension before 20 weeks. Incidence of superimposed preeclampsia was 43.3% (95% confidence interval (CI) 37.8–48.9). Women with superimposed preeclampsia were significantly more likely to have mean arterial pressure (MAP) ≥105 mmHg at 18–20 and 24–28 weeks. Adverse neonatal outcomes were significantly more common among women with superimposed preeclampsia, including small for gestational age, low birth weight, asphyxia, and neonatal intensive care unit admission. Logistic regression analysis demonstrated that only MAP ≥105 mmHg at 24–28 weeks was independently associated with the increased risk of superimposed preeclampsia by 1.8-fold (adjusted OR 1.8, 95% CI 1.1–3.1, p = 0.031).

Conclusion: Incidence of superimposed preeclampsia was 43.3% among pregnant women with chronic hypertension, with increased adverse neonatal outcomes. High MAP ≥105 mmHg during late second trimester might be an important predictor of the condition.     

Chronic hypertension is an independent risk factor for preeclampsia and preterm delivery in women with rheumatologic diseases: a population-based study

OBJECTIVE: The objective was to determine the prevalence of maternal and perinatal complications among patients with rheumatologic diseases (RD) and to investigate the maternal risk factors for preeclampsia and preterm delivery among RD patients. STUDY DESIGN: A retrospective population-based cohort study was conducted. The study group comprised women with RD; the control group comprised patients without RD. The obstetric and neonatal outcomes of the groups were compared, and the data were obtained from a computerized database. RESULTS: During the study period, there were 179 deliveries by 125 women with RD. The prevalence of severe preeclampsia, chronic hypertension, pregestational diabetes, oligohydramnios, preterm deliveries and cesarean sections was significantly higher in the RD group than in the control group. Mean birth weight was significantly lower in the study group compared with the general population. Maternal RD was found to be an independent risk factor for preterm delivery and severe preeclampsia (OR 3.59; 95% CI: 2.52-5.11; OR 3.05; 95% CI: 1.44-6.45, respectively). The presence of chronic hypertension in patients with RD was found to be an independent risk factor for severe preeclampsia and preterm delivery (OR 12.2; 95% CI: 2.1-69.8; OR 3.8; 95% CI: 1.1-12.7, respectively). CONCLUSION: Chronic hypertension is an independent risk factor for preterm delivery and severe preeclampsia among RD patients.     

Components of insulin resistance syndrome in a community-based population assessed by log-linear models.

BACKGROUND AND PURPOSE: To investigate the clustering of insulin resistance syndrome with hyperinsulinemia, hypertriglyceridemia, low high-density lipoprotein (HDL) cholesterol, hypertension, and obesity, we conducted this cross-sectional study and analyzed the patterns of conditional independence among these five elements. METHODS: Fasting insulin, lipid profiles, blood pressure, and anthropometric data from 2165 Taiwanese older than 35 years in the Chin-Shan community were examined. The cut-off points of these five factors (all binary variables) were defined. The hierarchical log-linear regression with nested effects model was applied to fit this higher-order contingency table of five variables, and likelihood ratio (chi2) statistics were used to test the goodness of fit. RESULTS: Hyperinsulinemia was independently correlated with obesity (odds ratio [OR] 5.7, 95% confidence interval [CI] 4.5-7.3), low HDL (OR 2.3, 95% CI 1.8-2.9), and hypertriglyceridemia (OR 1.6, 95% CI 1.2-2.2). Hypertriglyceridemia was significantly associated with low HDL (OR 3.6, 95% CI 2.7-4.8), and non-significantly associated with hypertension (OR 1.3, 95% CI 0.9-1.7) and obesity (OR 1.1, 95% CI 0.8-1.6). In persons with normal triglyceride levels, hypertension was positively associated with obesity (OR 2.8, 95% CI 2.1-3.7) and low HDL (OR 2.0, 95% CI 1.5-2.8). Analyses from forward and backward selection methods gave similar results. Graphical models with conditional independence relationships among these five variables were demonstrated. CONCLUSIONS: The components of insulin resistance syndrome have intricate relationships. Hyperinsulinemia was most related to obesity, and hypertriglyceridemia was most related to low HDL.     

Umbilical cord prolapse and perinatal outcomes.

OBJECTIVES: To determine obstetric risk factors and perinatal outcomes of pregnancies complicated by umbilical cord prolapse. METHODS: A population-based study was performed comparing all deliveries complicated by cord prolapse to deliveries without this complication. Statistical analysis was performed using multiple logistic regression models. RESULTS: Prolapse of the umbilical cord complicated 0.4% (n=456) of all deliveries included in the study (n=121,227). Independent risk factors for cord prolapse identified by a backward, stepwise multivariate logistic regression model were: malpresentation (OR=5.1; 95% CI 4.1-6.3), hydramnios (OR=3.0; 95% CI 2.3-3.9), true knot of the umbilical cord (OR=3.0; 95% CI 1.8-5.1), preterm delivery (OR=2.1; 95% CI 1.6-2.8), induction of labor (OR=2.2; 95% CI 1.7-2.8), grandmultiparity (>five deliveries, OR=1.9; 95% CI 1.5-2.3), lack of prenatal care (OR=1.4; 95% CI 1.02-1.8), and male gender (OR=1.3; 95% CI 1.1-1.6). Newborns delivered after umbilical cord prolapse graded lower Apgar scores, less than 7, at 5 min (OR=11.9, 95% CI 7.9-17.9), and had longer hospitalizations (mean 5.4+/-3.5 days vs. 2.9+/-2.1 days; P<0.001). Moreover, higher rates of perinatal mortality were noted in the cord prolapse group vs. the control group (OR=6.4, 95% CI 4.5-9.0). Using a multiple logistic regression model controlling for possible confounders, such as preterm delivery, hydramnios, etc., umbilical cord prolapse was found to be an independent contributing factor to perinatal mortality. CONCLUSIONS: Prolapse of the umbilical cord is an independent risk factor for perinatal mortality.     

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.     

Short stature--an independent risk factor for Cesarean delivery

OBJECTIVE: The present study was aimed to investigate pregnancy outcome of patients with short stature (height<155 cm), and specifically to elucidate if patients with short stature are at an increased risk for Cesarean section (CS) even after controlling for labor dystocia. METHODS: A population-based study comparing pregnancy outcome of patients with and without short stature, was performed. Deliveries occurred during the years 1988-2002, in a tertiary medical center. Stratified analyses, using the Mantel-Haenszel technique, and a multiple logistic regression model were performed to control for confounders. RESULTS: During the study period, 159,210 deliveries occurred. Of these, 5822 (3.65%) were of patients with short stature. Patients with short stature had statistically significant higher rates of CS compared with patients>or=155 cm (21.3% versus 11.9%, odds ratio (OR)=2.0; 95% confidence interval (CI): 1.9-2.1; P<0.001). Furthermore, there patients had higher rated of previous deliveries by CS (17.5% versus 10.3%, OR=1.8; 95% CI: 1.7-2.0; P<0.001), intrauterine growth restriction (IUGR, 3.2% versus 1.9%, OR=1.7; 95% CI: 1.4-1.9; P<0.001), premature rupture of membranes (PROM, 7.1% versus 5.6%, OR=1.3; 95% CI: 1.2-1.4; P<0.001), failed induction (0.7% versus 0.4%, OR=2.0; 95% CI: 1.5-2.8; P<0.001), labor dystocia (6.1% versus 3.5%, OR=1.8; 95% CI: 1.6-2.0; P<0.001), mal-presentations (7.6% versus 6.1%, OR=1.3; 95% CI: 1.1-1.4; P<0.001), and cephalopelvic disproportion (CPD, 0.9% versus 0.3%, OR=2.6; 95% CI: 1.9-3.4; P<0.001). No significant differences were noted between the groups regarding perinatal complications such as low birth-weight, meconium-stained amniotic fluid, perinatal mortality, and low Apgar scores at 5 min. Controlling for possible confounders such as previous CS, IUGR, PROM, failed induction, labor dystocia, mal-presentations and CPD, using the Mantel-Haenszel technique, did not change the significant association between short stature and CS. Moreover, a multiple logistic regression model was constructed with CS as the outcome variable, controlling for all these confounders. The model found short stature to be an independent risk factor for CS (OR=1.7; 95% CI: 1.6-1.9; P<0.001). CONCLUSION: Short stature is an independent risk factor for Cesarean delivery. Further studies investigating the actual indication for CS should be performed in order to make an informed recommendation regarding the preferred mode of delivery in short parturient women.     

Antenatal waist circumference and hypertension risk

OBJECTIVE: To assess whether waist circumference at the first antenatal visit predicts risk of developing hypertension later in pregnancy. METHODS: Pregnant women with singleton pregnancies (n = 1142, median age 29 years, interquartile range 25-32 years, 387 primigravidas) were recruited at their first antenatal visits. Using standardized methods, midwives determined the weights, heights (for calculation of body mass index [BMI]), and waist circumferences of all women. Eighty-two women developed pregnancy-induced hypertension, and 21 developed preeclampsia (hypertension with proteinuria). RESULTS: The median waist circumference between 6 and 16 weeks' gestation was 79 cm (interquartile range 72-84 cm), and there was no significant relationship between waist circumference and gestational age. Greater waist circumference was noted in subjects who subsequently developed pregnancy-induced hypertension (median 81 versus 77 cm, Mann-Whitney U test, P =.002) or preeclampsia (median 80 versus 77 cm, P =.02). The conventional, nonpregnant waist circumference action level of 80 cm gave a Mantel-Haenszel odds ratio (OR) for pregnancy-induced hypertension of 1.8 (95% confidence interval [CI] 1.1, 2.9) and for preeclampsia of 2.7 (95% CI 1.1, 6.8), compared with waists of less than 80 cm. Body mass index values were higher in women who developed pregnancy-induced hypertension (median 26 versus 24, P =.001) or preeclampsia (median 26 versus 24, P =.02). The conventional action limit for a BMI of 25 had an OR for pregnancy-induced hypertension of 2.0 (95% CI 1.2, 3.4) and for preeclampsia of 1.9 (95% CI 0.7, 4.8). Results were similar when the analysis was restricted to data from primigravidas. CONCLUSION: We conclude that waist circumference up to 16 weeks' gestation can predict pregnancy-induced hypertension and preeclampsia. Therefore, waist circumference could form the basis for health promotion involving raising awareness of the importance of or urging weight reduction for women planning pregnancies.     

Maternal asthma and risk of preeclampsia: a case-control study

OBJECTIVE: To quantify the associations between asthma characteristics and the risk of preeclampsia. STUDY DESIGN: In this case-control study, asthma history among 286 preeclampsia cases and 470 normotensive controls in Seattle was assessed by postpartum interview and medical record abstraction. OR and 95% CI were estimated using logistic regression. The sample size was adequate to detect unadjusted asthma history with ORs of > or =1.6 at a power of 80%. RESULTS: After adjustment, women with a history of prepregnancy asthma diagnosis were not at increased preeclampsia risk (OR 0.94, 95% CI 0.58-1.52). Women experiencing asthma symptoms during pregnancy were more likely than pregnant nonasthmatics to have preeclampsia (OR 2.20, 95% CI 0.79-6.10). Those with long-term pre-pregnancy asthma and symptoms during pregnancy were at particularly increased risk (OR 9.09, 95% CI 1.02-81.6). Point estimates were generally higher after restriction to women withfull-term deliveries. CONCLUSION: This analysis suggests that asthmatics, particularly those who are symptomatic during pregnancy, may be at higher risk of developing preeclampsia.     

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.     

Incidence of placental abruption in relation to cigarette smoking and hypertensive disorders during pregnancy: a meta-analysis of observational studies

OBJECTIVE: To systematically review the literature and summarize the relationship between cigarette smoking and placental abruption, and to evaluate the joint influences of smoking and hypertensive disorders (chronic hypertension and preeclampsia) on the subsequent development of abruption. DATA SOURCES: We reviewed studies identified through a MEDLINE literature search between 1966 and 1997 and through studies cited in the references of published reports. METHODS OF STUDY SELECTION: A total of 13 observational (seven case-control and six cohort) studies were identified which included a total of 1,358,083 pregnancies. We excluded case reports on placental abruption, and restricted the literature search to studies published in English. A meta-analysis was performed by computing pooled odds ratios based on random-effects models describing the association between placental abruption, smoking, and hypertensive disorders. Potential sources of heterogeneity among these studies were explored in detail. TABULATION, INTEGRATION, AND RESULTS: The overall incidence of placental abruption was 0.64% (8724 of 1,358,623). Smoking was associated with a 90% increase in the risk of placental abruption (odds ratio [OR] 1.9, 95% confidence interval [CI] 1.8, 2.0). This pattern was consistent by study design (case-control compared with cohort studies) and smoking prevalence (low compared with high prevalence, defined as less than 30% compared with 30% or more, respectively). However, the association was significantly (p < .001) stronger among the seven studies conducted outside the United States (OR 2.1, 95% CI 2.0, 2.2), compared with the six studies conducted in the United States (OR 1.6, 95% CI 1.5, 1.8). Pooled population attributable risk percentage for each stratum ranged between 15% and 25%, implying that 15-25% of placental abruption episodes are attributable to cigarette smoking. Data on the dose-response relationship between number of cigarettes smoked per day and the risk of abruption indicate that the OR increased with increasing number of cigarettes smoked. Furthermore, a meta-analysis of the joint effects of smoking and hypertension during pregnancy on the development of abruption identified two published studies, including 102,609 pregnancies. In the presence of smoking, the risk of abruption was further increased due to chronic hypertension, mild or severe preeclampsia, or chronic hypertension with superimposed preeclampsia. CONCLUSION: Our meta-analyses showed an increased risk for placental abruption in relation to both cigarette smoking and hypertensive disorders during pregnancy. Because cigarette smoking is a modifiable risk factor, and hypertensive disorders are potentially treatable if diagnosed early in pregnancy, patient education, smoking cessation programs, and early prenatal care may be important factors in the prevention of placental abruption.     

Pregnancy outcomes in systemic sclerosis, primary pulmonary hypertension, and sickle cell disease

OBJECTIVE: Systemic sclerosis, primary pulmonary hypertension, and sickle cell disease are uncommon vasculopathic diseases affecting women. We estimated the nationwide occurrence of pregnancies in women with these conditions and compared pregnancy outcomes to the general obstetric population. METHODS: We studied the 2002-2004 Nationwide Inpatient Sample, of the Healthcare Cost and Utilization Project to estimate the number of obstetric hospitalizations and deliveries among women with systemic sclerosis, primary pulmonary hypertension, sickle cell disease, and women in the general population. Pregnancy outcomes included length of hospital stay, hypertensive disorders including preeclampsia, intrauterine growth restriction (IUGR), and cesarean delivery. Multivariable regression analyses were performed using maternal age, race or ethnicity, antiphospholipid antibody syndrome, diabetes mellitus, and renal failure as covariates. RESULTS: Of an estimated 11.2 million deliveries, 504 occurred in women with systemic sclerosis, 182 with primary pulmonary hypertension, and 4,352 with sickle cell disease. Systemic sclerosis, was associated with an increased risk of hypertensive disorders including preeclampsia (odds ratio [OR] 3.71, 95% confidence interval [CI] 2.25-6.15), IUGR (OR 3.74, 95% CI 1.51-9.28), and increased length of hospital stay. Primary pulmonary hypertension was associated with an increase in the odds of antenatal hospitalization (OR 4.67, 95% CI 2.88-7.57), hypertensive disorders including preeclampsia (OR 5.62, 95% CI 2.60-12.15) and a substantial increase in length of hospital stay. Sickle cell disease was associated with an increased odds of antenatal hospitalization (OR 5.56 95% CI 5.08-6.09), hypertensive disorders including preeclampsia (OR 1.78, 95% CI 1.48-2.14), and IUGR (OR 2.91, 95% CI 2.16-3.93), with a modest increase in length of hospital stay. CONCLUSION: Women with systemic sclerosis, primary pulmonary hypertension, and sickle cell disease have significantly increased rates of adverse pregnancy outcomes, requiring extensive preconceptional counseling about the risks of pregnancy.     

Risk of maternal postpartum readmission associated with mode of delivery

OBJECTIVE: To determine whether cesarean and operative vaginal deliveries are associated with an increased risk of maternal rehospitalization compared with spontaneous vaginal delivery. METHODS: A population-based cohort study was conducted by using the Canadian Institute for Health Information's Discharge Abstract Database between 1997/1998 and 2000/2001, which included 900,108 women aged 15-44 years with singleton live births (after excluding several selected obstetric conditions). RESULTS: A total of 16,404 women (1.8%) were rehospitalized within 60 days after initial discharge. Compared with spontaneous vaginal delivery (rate 1.5%), cesarean delivery was associated with a significantly increased risk of postpartum readmission (rate 2.7%, odds ratio [OR] 1.9, 95% confidence interval [CI] 1.8-1.9); ie, there was 1 excess postpartum readmission per 75 cesarean deliveries. Diagnoses associated with significantly increased risks of readmission after cesarean delivery (compared with spontaneous vaginal delivery) included pelvic injury/wounds (rate 0.86% versus 0.06%, OR 13.4, 95% CI 12.0-15.0), obstetric complications (rate 0.23% versus 0.08%, OR 3.0, 95% CI 2.6-3.5), venous disorders and thromboembolism (rate 0.07% versus 0.03%, OR 2.7, 95% CI 2.1-3.4), and major puerperal infection (rate 0.45% versus 0.27%, OR 1.8, 95% CI 1.6-1.9). Women delivered by forceps or vacuum were also at an increased risk of readmission (rates 2.2% and 1.8% versus 1.5%; OR forceps: 1.4, 95% CI 1.3-1.5; OR vacuum: 1.2, 95% CI 1.2-1.3, respectively). Higher readmission rates after operative vaginal delivery were due to pelvic injury/wounds, genitourinary conditions, obstetric complications, postpartum hemorrhage, and major puerperal infection. CONCLUSION: Compared with spontaneous vaginal delivery, cesarean delivery, and operative vaginal delivery increase the risk of maternal postpartum readmission. LEVEL OF EVIDENCE: II-2.     

Identifying risk factors for peripartum cesarean hysterectomy. A population-based study

OBJECTIVE: To determine the incidence of, and obstetric risk factors for, emergency peripartum hysterectomy. STUDY DESIGN: A population-based study comparing all singleton deliveries between the years 1988 and 1999 that were complicated with peripartum hysterectomy to deliveries without this complication. Statistical analysis was performed with multiple logistic regression analysis. RESULTS: Emergency peripartum hysterectomy complicated 0.048% (n = 56) of deliveries in the study (n = 117,685). Independent risk factors for emergency peripartum hysterectomy from a backward, stepwise, multivariable logistic regression model were: uterine rupture (OR = 521.4, 95% CI 197.1-1379.7), placenta previa (OR = 8.2, 95% CI 2.2-31.0), postpartum hemorrhage (OR = 33.3, 95% CI 12.6-88.1), cervical tears (OR = 18.0, 95% CI 6.2-52.4), placenta accreta (OR = 13.2, 95% CI 3.5-50.0), second-trimester bleeding (OR = 9.5, 95% CI 2.3-40.1), previous cesarean section (OR = 6.9, 95% CI 3.7-12.8) and grand multiparity (> 5 deliveries) (OR = 3.4, 95% CI 1.8-6.3). Newborns delivered after peripartum hysterectomy had lower Apgar scores (< 7) at 1 and 5 minutes than did others (OR = 11.5, 95% CI 6.2-20.9 and OR = 27.4, 95% CI 11.2-67.4, respectively). In addition, higher rates of perinatal mortality were noted in the uterine hysterectomy vs. the comparison group (OR = 15.9, 95% CI 7.5-32.6). Affected women were more likely than the controls to receive packed-cell transfusions (OR = 457.7, 95% CI 199.2-1105.8) and had lower hemoglobin levels at discharge from the hospital (9.9 +/- 1.3 vs. 12.8 +/- 5.7, P < .001). CONCLUSION: Cesarean deliveries in patients with suspected placenta accreta, specifically those performed due to placenta previa in women with a previous uterine scar, should involve specially trained obstetricians. In addition, detailed informed consent about the possibility of emergency peripartum hysterectomy and its associated morbidity should be obtained.     

Prediction of superimposed preeclampsia using uterine artery Doppler velocimetry in women with chronic hypertension

OBJECTIVE: To assess the role of uterine artery (UtA) Doppler to predict superimposed preeclampsia in women with chronic hypertension. METHODS: In a cohort of 182 women with chronic hypertension, UtA Doppler studies were performed before 25 weeks (mean 19.7 +/- 2.1 weeks) and repeated later in pregnancy (mean 28.5 +/- 3.7 weeks). RESULTS: The incidence of preeclampsia was 13% (24/182). Rates of preeclampsia increased with advancing gestation of abnormal UtA Doppler: 7% when UtA Doppler were normal at early exam, 18% when abnormal at early exam, and 28% when abnormal at late exam (Chi-square for trend: P < 0.001). The rate of preeclampsia among 40 women with abnormal early but normal late UtA Doppler was similar to that of women with normal findings at early exam (8 vs 7%; P = 1.00). Logistic regression analysis showed that the ability of UtA Doppler to predict preeclampsia was independent from other variables [Odds Ratio (OR) 7.1, 95% Confidence Interval (CI) 2.6-18.9). Receiver operating characteristic (ROC) curve identified a UtA value of 0.58 as the optimal threshold for the prediction of preeclampsia. CONCLUSION: The later in pregnancy the abnormal UtA Doppler findings are observed, the greater the risk of preeclampsia. Normalization of UtA Doppler after 25 weeks reduces the risk of preeclampsia to 8%.