Clinical and Physician Factors Associated With Failed Operative Vaginal Delivery.

OBJECTIVE: To examine clinical and physician factors associated with failed operative vaginal delivery among individuals with nulliparous, term, singleton, vertex (NTSV) births. METHODS: This was a retrospective cohort study of individuals with NTSV live births with an attempted operative vaginal delivery by a physician between 2016 and 2020 in California. The primary outcome was cesarean birth after failed operative vaginal delivery, identified using linked diagnosis codes, birth certificates, and physician licensing board data stratified by device type (vacuum or forceps). Clinical and physician-level exposures were selected a priori, defined using validated indices, and compared between successful and failed operative vaginal delivery attempts. Physician experience with operative vaginal delivery was estimated by calculating the number of operative vaginal delivery attempts made per physician during the study period. Multivariable mixed effects Poisson regression models with robust standard errors were used to estimate risk ratios of failed operative vaginal delivery for each exposure, adjusted for potential confounders. RESULTS: Of 47,973 eligible operative vaginal delivery attempts, 93.2% used vacuum and 6.8% used forceps. Of all operative vaginal delivery attempts, 1,820 (3.8%) failed; the success rate was 97.3% for vacuum attempts and 82.4% for forceps attempts. Failed operative vaginal deliveries were more likely with older patient age, higher body mass index, obstructed labor, and neonatal birth weight more than 4,000 g. Between 2016 and 2020, physicians who attempted more operative vaginal deliveries were less likely to fail. When vacuum attempts were successful, physicians who conducted them had a median of 45 vacuum attempts during the study period, compared with 27 attempts when vacuum attempts were unsuccessful (adjusted risk ratio [aRR] 0.95, 95% CI 0.93-0.96). When forceps attempts were successful, physicians who conducted them had a median of 19 forceps attempts, compared with 11 attempts when forceps attempts were unsuccessful (aRR 0.76, 95% CI 0.64-0.91). CONCLUSION: In this large, contemporary cohort with NTSV births, several clinical factors were associated with operative vaginal delivery failure. Physician experience was associated with operative vaginal delivery success, more notably for forceps attempts. These results may provide guidance for physician training in maintenance of operative vaginal delivery skills.

Late breeding season definitive prebasic molt in males, and late breeding season brood care by females, in central California Wilson's warblers.

I made observations of a central California population of Wilson's Warbler, Cardellina pusilla, after July 1 over 10 breeding seasons. I sighted males in definitive prebasic molt from July 4 (in 2007) to September 1 (in 1999). Most territorial males molted on their breeding territories, and individual molt lasted up to 46 days. Following prebasic molt, territorial males engaged in subdued "post-molt singing," which lasted about 7 days in some males, and which I first heard on August 13 (in 2004) and last heard on September 6 (in 1999). I sighted no female in definitive prebasic molt, or in fresh basic plumage, during the study. Of 13 females sighted ≥ July 21, 11 were in late breeding season uniparental brood care, and I could not rule out late brood care for the other two. Most, and possibly all, females not engaged in late season uniparental brood care apparently vacated their breeding territories before July 21. This departure was much earlier than for resident males, the last of which I sighted on September 10 (in 1999). Early-departing females presumably underwent prebasic molt after July 21 at locations not known. Remaining late-nesting females must have molted much later than resident males and likely later than early-departing females, and at locations unknown. I last sighted two uniparental brood-tending females, still in worn plumage, on August 26 and 29, respectively. Two unique findings of this study are a male/female difference in location of prebasic molt, and a likely dichotomy of prebasic molt timing between females leaving their breeding territories early and those remaining in uniparental brood care. Another finding, post-molt singing in most and possible all territorial males, is a largely unrecognized behavior, but one previously reported in several passerine species. Post-molt singing may reliably indicate completion of prebasic molt.

Severe maternal and neonatal morbidity after attempted operative vaginal delivery.

BACKGROUND: Operative vaginal delivery is a critical tool in reducing primary cesarean delivery, but declining operative vaginal delivery rates and concerns about provider skill necessitate a clear understanding of risks. These risks are ambiguous because most studies compare outcomes of operative vaginal delivery with that of spontaneous vaginal delivery rather than outcomes of cesarean delivery in the second stage of labor, which is usually the realistic alternative. OBJECTIVE: This study aimed to compare severe maternal and neonatal morbidity by mode of delivery of patients with a prolonged second stage of labor who had a successful operative vaginal delivery, a cesarean delivery after failed operative vaginal delivery, or a cesarean delivery without an operative vaginal delivery attempt. STUDY DESIGN: We used a population-based database to evaluate nulliparous, term, singleton, vertex live births in California between 2007 and 2012 of patients with prolonged second stage of labor. Birth certificates and the International Classification of Diseases, Ninth Revision, Clinical Modification coded diagnoses and procedures were used for ascertainment of exposure, outcome, and demographics. Exposure was mode of delivery of patients who had any operative vaginal delivery attempt vs cesarean delivery without operative vaginal delivery attempt. The outcomes were severe maternal morbidity and severe unexpected newborn morbidity, defined using established indices. Anticipating that the code for prolonged second stage of labor would represent only a fraction of true operative vaginal delivery candidates, a secondary analysis was conducted removing this restriction to explore granular outcomes in a larger cohort with unsuccessful labor. Multivariable logistic regression was used to compare outcomes by mode of delivery adjusted for measured confounders. Sensitivity analyses were done excluding patients with combined vacuum-forceps-assisted delivery and birthweight of >4000 g. RESULTS: A total of 9239 births after prolonged second stage of labor were included, where 6851 (74.1%) were successful operative vaginal deliveries, 301 (3.3%) were failed operative vaginal deliveries, and 2087 (22.6%) were cesarean deliveries without operative vaginal delivery attempts. Of successful operative vaginal deliveries, 6195 (90.4%) were vacuum assisted and 656 (10.6%) were forceps-assisted. Of failed operative vaginal deliveries where operative vaginal delivery type was specified, 83 (47.4%) were vacuum assisted, 38 (21.7%) were forceps-assisted, and 54 (30.9%) were combined vacuum-forceps-assisted. Of note, all 54 combined vacuum-forceps-assisted operative vaginal delivery attempts that we identified failed. The outcomes of patients with failed operative vaginal delivery differed from those with successful operative vaginal delivery, such as higher rates of comorbidities, use of combined operative vaginal delivery, and birthweight of >4000 g. Successful operative vaginal delivery was associated with reduced severe maternal morbidity (adjusted odds ratio, 0.55; 95% confidence interval, 0.39-0.78) without a difference in severe unexpected neonatal morbidity (adjusted odds ratio, 0.99; 95% confidence interval, 0.78-1.26). In contrast, failed operative vaginal delivery was associated with increased severe maternal morbidity (adjusted odds ratio, 2.14; 95% confidence interval, 1.20-3.82) and severe unexpected neonatal morbidity (adjusted odds ratio, 1.78; 95% confidence interval, 1.09-2.86). In addition, findings were similar in the secondary analysis of 260,585 patients with unsuccessful labor. CONCLUSION: In this large cohort of nulliparous, term, singleton, vertex births, successful operative vaginal delivery was associated with a 45% reduction in severe maternal morbidity without differences in severe unexpected neonatal morbidity compared with cesarean delivery after prolonged second stage of labor. Operative vaginal delivery infrequently failed and was associated with a 214% increase in severe maternal morbidity and a 78% increase in severe unexpected neonatal morbidity; furthermore, combined operative vaginal deliveries were major contributors to this, as all combined operative vaginal deliveries failed. Optimization of operative vaginal delivery success rates through means such as improved patient selection, enhanced provider skill, and discussions against combined operative vaginal delivery could reduce maternal and neonatal complications.

The Impact of maternal obesity and race/ethnicity on perinatal outcomes: Independent and joint effects.

OBJECTIVE: Independent and joint impacts of maternal race/ethnicity and obesity on adverse birth outcomes, including pre-eclampsia, low birth weight, and macrosomia, were characterized. METHODS: Retrospective cohort study of all 2007 California births was conducted using vital records and claims data. Maternal race/ethnicity and maternal body mass index (BMI) were the key exposures; their independent and joint impact on outcomes using regression models was analyzed. RESULTS: Racial/ethnic minority women of normal weight generally had higher risk as compared with white women of normal weight (e.g., African-American women, pre-eclampsia adjusted odds ratio [aOR] 1.60, 95% confidence interval [CI]: 1.48-1.74 vs. white women). However, elevated BMI did not usually confer additional risk (e.g., pre-eclampsia aOR comparing African-American women with excess weight with white women with excess weight, 1.17, 95% CI: 0.89-1.54). Obesity was a risk factor for low birth weight only among white women (excess weight aOR, 1.24, 95% CI: 1.04-1.49 vs. white women of normal weight) and not among racial/ethnic minority women (e.g., African-American women, 0.95, 95% CI: 0.83-1.08). CONCLUSIONS: These findings add nuance to our understanding of the interplay between maternal race/ethnicity, BMI, and perinatal outcomes. While the BMI/adverse outcome gradient appears weaker in racial/ethnic minority women, this reflects the overall risk increase in racial/ethnic minority women of all body sizes.

Effect of time of birth on maternal morbidity during childbirth hospitalization in California.

OBJECTIVE: This observational study aimed to determine the relationship between time of birth and maternal morbidity during childbirth hospitalization. STUDY DESIGN: Composite maternal morbidities were determined using International Classification of Diseases, Ninth Revision, Clinical Modification and vital records codes, using linked hospital discharge and vital records data for 1,475,593 singleton births in California from 2005 through 2007. Time of birth, day of week, and sociodemographic, obstetric, and hospital volume risk factors were estimated using mixed effects logistic regression models. RESULTS: The odds for pelvic morbidity were lowest between 11 PM-7 AM compared to other time periods and the reference value of 7-11 AM. The odds for pelvic morbidity peaked between 11 AM-7 PM (adjusted odds ratio [AOR], 1101-1500 = 1.07; 95% confidence interval [CI], 1.06-1.09; 1501-1900 = 1.08; 95% CI, 1.06-1.10). Odds for severe morbidity were higher between 11 PM-7 AM (AOR, 2301-0300 = 1.31; 95% CI, 1.21-1.41; 0301-0700 = 1.30; 95% CI, 1.20-1.41) compared to other time periods. The adjusted odds were not statistically significant for weekend birth on pelvic morbidity (AOR, Saturday = 1.00; 95% CI, 0.98-1.02]; Sunday = 1.01; 95% CI, 0.99-1.03) or severe morbidity (AOR, Saturday = 1.09; 95% CI, 1.00-1.18; Sunday = 1.03; 95% CI, 0.94-1.13). Cesarean birth, hypertensive disorders, birthweight, and sociodemographic factors that include age, race, ethnicity, and insurance status were also significantly associated with severe morbidity. CONCLUSION: Even after controlling for sociodemographic factors and known risks such as cesarean birth and pregnancy complications such as hypertensive disorders, birth between 11 PM-7 AM is a significant independent risk factor for severe maternal morbidity.

Pregnancy outcomes in the super obese, stratified by weight gain above and below institute of medicine guidelines.

OBJECTIVE: To examine the association of antenatal weight gain above and below the 2009 Institute of Medicine (IOM) guidelines in the super-obese population (body mass index [BMI] of 50 or higher) on the maternal and neonatal morbidities of gestational hypertension or preeclampsia (pregnancy-induced hypertension), gestational diabetes mellitus, cesarean delivery, birth weight more than 4,000 g and more than 4,500 g, low birth weight, and preterm birth. METHODS: The effect of gestational weight gain was assessed in this retrospective cohort study using California birth certificate and patient discharge diagnosis data. Unconditional logistic regression was used to calculate adjusted odds ratios (ORs) and 95% confidence intervals (CIs) as a function of antenatal weight gain. Weight gain within 2009 IOM guidelines (11-20 pounds) served as the reference group. RESULTS: The study population consisted of 1,034 women. Women gaining below, within, and above IOM guidelines accounted for 38.3, 23.5, and 38.2%, respectively. Weight gain below IOM guidelines was not associated with a statistically increased odds of preterm birth (OR 1.82, 95% CI 0.60-5.59) or low birth weight (OR 1.20, 95% CI 0.57-2.49); however, birth weight more than 4,000 g was significantly reduced (OR 0.50, 95% CI 0.32-0.77). Excessive weight gain statistically increased the odds of pregnancy-induced hypertension (OR 1.96, 95% CI 1.26-3.03) and cesarean delivery (OR 1.40, 95% CI 1.00-1.97) while not appearing to protect against the delivery of low-birth-weight neonates (OR 0.84, 95% CI 0.40-1.78). CONCLUSION: Weight gain below the current guidelines in the super-obese cohort is not associated with an increase in maternal or neonatal risk while decreasing the odds of delivering a macrosomic neonate. Women with BMIs of 50 or higher may warrant separate gestational weight gain recommendations.

The impact of change in pregnancy body mass index on macrosomia.

OBJECTIVE: To examine the impact of change in body mass index (BMI) during pregnancy on the incidence of macrosomia. METHODS: This is a retrospective cohort study using 2007 linked birth certificate and discharge diagnosis data from the state of California. Adjusted odds ratios (aOR) with 95% confidence intervals (CI) were calculated for the outcome of macrosomia, as a function of a categorical change in pregnancy BMI: BMI loss (<-0.5), no change (-0.5 to 0.5), minimal (0.6 to 5), moderate (5.1 to 10), and excessive (>10). The impact of pregnancy change in BMI was determined for the entire cohort and then stratified by prepregnancy BMI category. Minimal BMI change served as the reference group. RESULTS: The study population consisted of 436,414 women. Overall, women with moderate and excessive BMI changes had aORs of 1.66 and 3.21, respectively, for macrosomia, when compared with women with minimal BMI change. When stratified by prepregnancy BMI, normal (aOR 3.85) and overweight women (aOR 2.96) with antenatal BMI change greater than 10 had the highest odds of macrosomia. CONCLUSIONS: Excessive change in pregnancy BMI results in an increased odds of macrosomia. This finding was most pronounced in the normal and overweight women.

The impact of change in pregnancy body mass index on cesarean delivery.

OBJECTIVE: To examine the impact of pregnancy changes in body mass index (BMI) on the incidence of cesarean delivery. METHODS: This is a retrospective cohort study using linked birth certificate and discharge diagnosis data from the year 2007. Adjusted odds ratios (aOR) were calculated for the outcome of cesarean delivery, as a function of a categorical change in pregnancy BMI (kg/m(2)): BMI loss (BMI change<-0.5), no change (-0.5 to 0.5), minimal (0.6 to 5), moderate (5.1 to 10) and excessive (>10). The impact of pregnancy change in BMI was determined for the entire cohort and then stratified by prepregnancy BMI category. RESULTS: The study population consisted of 436 414 women with singleton gestations. When compared to women with no net change in BMI, women with excessive BMI changes collectively had a 80% increased incidence of cesarean delivery (aOR = 1.78). By prepregnancy obesity class, the aOR for cesarean delivery in women with excessive BMI change were: normal weight (aOR = 2.25), overweight (aOR = 2.39), obese class I (aOR = 2.23), obese class II (aOR = 2.56) and obese class III (aOR = 2.08). CONCLUSIONS: The odds of cesarean delivery were uniformly increased in all prepregnancy BMI categories as net BMI change increased. These data illustrate that all women, not just the overweight and obese, are at significantly increased risk of cesarean delivery with excessive BMI change during pregnancy.

Maternal diagnosis of obesity and risk of cerebral palsy in the child.

OBJECTIVE: To examine the association between maternal hospital diagnoses of obesity and risk of cerebral palsy (CP) in the child. STUDY DESIGN: For all California hospital births from 1991-2001, we linked infant and maternal hospitalization discharge abstracts to California Department of Developmental Services records of children receiving services for CP. We identified maternal hospital discharge diagnoses of obesity (International Classification of Diseases, 9th edition 646.1, 278.00, or 278.01) and morbid obesity (International Classification of Diseases, 9th edition 278.01), and performed logistic regression to explore the relationship between maternal obesity diagnoses and CP. RESULTS: Among 6.2 million births, 67 200 (1.1%) mothers were diagnosed with obesity, and 7878 (0.1%) with morbid obesity; 8798 (0.14%) children had CP. A maternal diagnosis of obesity (relative risk [RR] 1.30, 95% CI 1.09-1.55) or morbid obesity (RR 2.70, 95% CI 1.89-3.86) was associated with increased risk of CP. In multivariable analysis adjusting for maternal race, age, education, prenatal care, insurance status, and infant sex, both obesity (OR 1.27, 95% CI 1.06-1.52) and morbid obesity (OR 2.56, 95% CI 1.79-3.66) remained independently associated with CP. On stratified analyses, the association of obesity (RR 1.72, 95% CI 1.25-2.35) or morbid obesity (RR 3.79, 95% CI 2.35-6.10) with CP was only significant among women who were hospitalized prior to the birth admission. Adjusting for potential comorbidities and complications of obesity did not eliminate this association. CONCLUSIONS: Maternal obesity may confer an increased risk of CP in some cases. Further studies are needed to confirm this finding.

Improving recording accuracy, transparency, and performance for obstetric quality measures in a community hospital-based obstetrics department.

BACKGROUND: The obstetric arena has been typically ignored in the race to determine hospital quality measures due primarily to the fact that a large majority of patients do not have Medicare federal insurance, which has been the focus of hospital measures of quality. With "normal vaginal delivery" being the number one hospital discharge diagnosis and cesarean sections rates varying greatly between hospitals, national organizations are taking greater interest in determining differences in quality. METHODS: Sutter Medical Center, Sacramento (California) chartered a multidisciplinary Perinatal Data Committee to improve and simplify data capture for six obstetric quality measures. RESULTS: All six quality measures showed significantly improved trends from 2010 through 2012, with elective delivery < 39 weeks decreasing (15.3% to 2.3%, p < .001), nulliparous term singleton vertex cesarean (NTSV) delivery rate decreasing (31.3% to 24.7%, p < .001), episiotomy rates decreasing (4.7% to 2.3%, p < .001), antenatal steroid documentation increasing (80.0% to 100%, p <.01), exclusive breastfeeding at hospital discharge increasing (57.9% to 69.9%, p <.001), and deep vein prophylaxis at cesarean increasing (95.4% to 98.2%,p < .001). CONCLUSION: That performance on all six quality measures improved suggests that the improvement approach was effective and perhaps reproducible in other clinical situations to improve hospital quality outcomes. A key contributor to success was that the dashboard of results was shared with the department's physicians and the hospital administration on a monthly basis. Reinforcement of good results helped keep the project front and center with the hospital, particularly more recently, given that data reporting for four of the six measures is soon to be required.

Maternal morbidity during childbirth hospitalization in California.

OBJECTIVE: To determine the incidence and risk factors for maternal morbidity during childbirth hospitalization. METHODS: Maternal morbidities were determined using ICD9-CM and vital records codes from linked hospital discharge and vital records data for 1,572,909 singleton births in California during 2005-2007. Socio-demographic, obstetric and hospital volume risk factors were estimated using mixed effects logistic regression models. RESULTS: The maternal morbidity rate was 241/1000 births. The most common morbidities were episiotomy, pelvic trauma, maternal infection, postpartum hemorrhage and severe laceration. Preeclampsia (adjusted odds ratio [AOR]: 2.96; 95% confidence interval 2.8,3.13), maternal age over 35 years, (AOR: 1.92; 1.79,2.06), vaginal birth after cesarean, (AOR: 1.81; 1.47,2.23) and repeat cesarean birth (AOR: 1.99; 1.87,2.12) conferred the highest odds of severe morbidity. Non-white women were more likely to suffer morbidity. CONCLUSIONS: Nearly one in four California women experienced complications during childbirth hospitalization. Significant health disparities in maternal childbirth outcomes persist in the USA.

Autism risk in small- and large-for-gestational-age infants.

OBJECTIVE: We sought to determine whether small-for-gestational age (SGA) and large-for-gestational age (LGA) birthweights increase autism risk. STUDY DESIGN: This was a retrospective cohort analysis comparing children with autism (n = 20,206) within a birth cohort (n = 5,979,605). Stratification by sex and birthweight percentile (SGA, <5th or 5-10th percentile; appropriate size for gestational age [GA], >10th to <90th percentile; LGA, either 90-95th or >95th percentile) preceded Cochran-Mantel-Haenszel analysis for GA effect, and multivariate analysis. RESULTS: Autism risk was increased in preterm SGA (<5th percentile) infants 23-31 weeks (adjusted odds ratio [aOR], 1.60; 95% confidence interval [CI], 1.09-2.35) and 32-33 weeks (aOR, 1.83; 95% CI, 1.16-2.87), and term LGA (>95th percentile) infants 39-41 weeks (aOR, 1.16; 95% CI, 1.08-1.26), but was decreased in preterm LGA infants 23-31 weeks (aOR, 0.45; 95% CI, 0.21-0.95). CONCLUSION: SGA was associated with autism in preterm infants, while LGA demonstrated dichotomous risk by GA, with increased risk at term, and decreased risk in the premature infants. These findings likely reflect disparate pathophysiologies, and should influence prenatal counseling, pediatric autism screening, and further autism research.

Cerebral palsy among Asian ethnic subgroups.

OBJECTIVE: Asians have a reduced risk for cerebral palsy (CP) compared with whites. We examined whether individual Asian subgroups have a reduced risk of CP and whether differences in sociodemographic factors explain disparities in CP prevalence. METHODS: In a retrospective cohort of 629 542 Asian and 2 109 550 white births in California from 1991 to 2001, we identified all children who qualified for services from the California Department of Health Services on the basis of CP. Asians were categorized as East Asian (Chinese, Japanese, Koreans), Filipino, Indian, Pacific Islander (Guamanians, Hawaiians, and Pacific Islanders), Samoan, or Southeast Asian (Cambodian, Laotian, Thai, Vietnamese). RESULTS: Overall, CP prevalence was lower in Asians than whites (1.09 vs 1.36 per 1000; relative risk = 0.80, 95% confidence interval [CI] = 0.74-0.87) and ranged from 0.61/1000 in Thai children to 2.08/1000 in Samoan children. Several Asian subgroups had low risk profiles with respect to maternal age, educational attainment, and birth weight. However, after we adjusted for maternal age and education, infant gender, and birth weight, the adjusted risk of CP remained lower in East Asians (odds ratio [OR] = 0.75, 95% CI = 0.65-0.87), Filipinos (OR = 0.87, 95% CI = 0.75-0.99), Indians (OR = 0.59, 95% CI = 0.44-0.80), Pacific Islanders (OR = 0.62, 95% CI = 0.40-0.97), and Southeast Asians (OR = 0.68, 95% CI = 0.57-0.82) compared with whites. CONCLUSIONS: Most Asian national origin subgroups have a lower rate of CP than whites, and this disparity is unexplained. Additional studies that focus on the cause of ethnic disparities in CP may provide new insights into pathogenesis and prevention.

Risk factors associated with cerebral palsy in preterm infants.

OBJECTIVE: To examine pregnancy outcomes in preterm delivered children with cerebral palsy (CP). METHODS: A retrospective population-based cohort study of children born in California (January 1, 1991 and December 31, 2001) with CP were identified (State databases) and compared to children without CP. We examined demographic data and pregnancy outcomes by gestational age groups controlling for multiple co-founders. RESULTS: Of 2733 preterm infants (total of 8397, 33% <37 weeks of gestation) with CP, delivery <28 weeks had the largest impact upon the development of CP (Odds ratio (OR) 18.2 95%CI (16.7, 19.9)) with delivery 28-31 6/7 weeks having less impact (OR 8.8 (8.0, 9.7) when compared to term deliveries. Birth asphyxia (OR 5.9 (5.3, 6.6) was associated with the future development of CP as were birth defects (OR 4.3 (4.1. 4.5), cord prolapse (OR 2.0 (1.6, 2.4)) and fetal distress (OR 2.1 (1.9, 2.2)) the latter 2 being less so. CONCLUSION: Prematurity had the greatest impact upon the future development of CP; however, birth asphyxia, birth defects and adverse labor events contributed significantly to the future development of CP as well, suggesting that the cause of CP in the preterm infant is most likely multifactorial.

Increasing pre-pregnancy body mass index is predictive of a progressive escalation in adverse pregnancy outcomes.

OBJECTIVE: To evaluate the association between pre-pregnancy body mass index (BMI) and adverse pregnancy outcomes using a large administrative database. METHODS: Retrospective cohort study of California women delivering singletons in 2007. The association between pre-pregnancy BMI category and adverse outcomes were evaluated using multivariate logistic regression. RESULTS: Among 436,414 women, increasing BMI was associated with increasing odds of adverse outcomes. Obese women (BMI=30-39.9) were nearly 3 x more likely to have gestational diabetes (OR=2.83, 95% CI=2.74-2.92) and gestational hypertension/preeclampsia (2.68, 2.59-2.77) and nearly twice as likely to undergo cesarean (1.82, 1.78-1.87), when compared to normal BMI women (BMI=18.5-24.9). Morbidly obese women (BMI ≥ 40) were 4x more likely to have gestational diabetes (4.72, 4.46-4.99) and gestational hypertension/preeclampsia (4.22, 3.97-4.49) and nearly 3 x as likely to undergo cesarean (2.60, 2.46-2.74). CONCLUSION: There is a strong association between increasing maternal BMI and adverse pregnancy outcomes. This information is important for counseling women regarding the risks of obesity in pregnancy.

Racial, ethnic, and socioeconomic disparities in the prevalence of cerebral palsy.

OBJECTIVE: Racial and ethnic disparities in cerebral palsy have been documented, but the underlying mechanism is poorly understood. We determined whether low birth weight accounts for ethnic disparities in the prevalence of cerebral palsy and whether socioeconomic factors impact cerebral palsy within racial and ethnic groups. METHODS: In a retrospective cohort of 6.2 million births in California between 1991 and 2001, we compared maternal and infant characteristics among 8397 infants with cerebral palsy who qualified for services from the California Department of Health Services and unaffected infants. RESULTS: Overall, black infants were 29% more likely to have cerebral palsy than white infants (relative risk: 1.29 [95% confidence interval: 1.19-1.39]). However, black infants who were very low or moderately low birth weight were 21% to 29% less likely to have cerebral palsy than white infants of comparable birth weight. After we adjusted for birth weight, there was no difference in the risk of cerebral palsy between black and white infants. In multivariate analyses, women of all ethnicities who did not receive any prenatal care were twice as likely to have infants with cerebral palsy relative to women with an early onset of prenatal care. Maternal education was associated with cerebral palsy in a dose-response fashion among white and Hispanic women. Hispanic adolescent mothers (aged <18 years) had increased risk of having a child with cerebral palsy. CONCLUSIONS: The increased risk of cerebral palsy among black infants is primarily related to their higher risk of low birth weight. Understanding how educational attainment and use of prenatal care impact the risk of cerebral palsy may inform new prevention strategies.

Adverse obstetric events are associated with significant risk of cerebral palsy.

OBJECTIVE: To examine adverse birth events on the development of cerebral palsy in California. STUDY DESIGN: A retrospective population-based study of children with cerebral palsy (as of Nov. 30, 2006), matched to their maternal/infant delivery records (Jan. 1, 1991 to Dec. 31, 2001) was performed. Demographic data and intrapartum events were examined. Six adverse birth-related events were chosen. Children without cerebral palsy were controls. RESULTS: There were 7242 children who had cerebral palsy (59% term) and 31.3% had 1 or more of the 6 adverse intrapartum events (12.9% in controls P < .0001). This held for both term (28.3% vs 12.7% controls) and preterm (36.8% vs 15.9%, controls) neonates (both P < .0001). Maternal (15.1% vs 6.6%) and neonatal (0.9% vs 0.1%) infection were increased in cerebral palsy cases (P < .0001). CONCLUSION: Almost one-third of children with cerebral palsy had at least 1 adverse birth-related event. Higher rates in the preterm group may partially explain the higher rates of cerebral palsy in this group.

Pregnancy outcomes in women with chronic hypertension: a population-based study.

OBJECTIVE: To determine the pregnancy outcomes associated with maternal chronic hypertension. STUDY DESIGN: Retrospective, population-based cohort study of maternal and infant discharge records linked to birth records in California from 1991 to 2001 were examined for demographics and pregnancy outcomes, and comparisons were made between those with and without chronic hypertension. One randomly selected pregnancy per subject was included. RESULTS: The number of women who delivered with chronic hypertension (0.69% incidence) was 29,842. As compared to non-chronic hypertensive patients, fetal and neonatal mortality and in-hospital maternal mortality were increased (ORs and 95% CIs 2.3, (2.1, 2.6); 2.3, (2.0, 2.7); and 4.8, (3.1, 7.6) respectively). Major maternal morbidity was increased: stroke, OR 5.3, (3.7, 7.5); renal failure, OR 6.0, (4.4, 8.1); pulmonary edema, OR 5.2, (3.9, 6.7); severe preeclampsia, OR 2.7, (2.5, 2.9); and placental abruption OR 2.1, (2.0, 2.3). Neonatal morbidity was increased as well: fetal growth restriction, OR 4.9, (4.7, 5.2); prematurity, OR 3.2, (3.1, 3.3); low birth weight, OR 5.4, (5.2, 5.5); very low birth weight, OR 6.5, (6.2, 6.8); and respiratory distress syndrome, OR 4.0, (3.8, 4.2). CONCLUSION: Pregnant women with chronic hypertension have significantly increased risks of maternal and perinatal morbidity and mortality. Women with this condition should be treated as high risk with appropriate maternal and fetal surveillance.