Impact of sickle cell disease and thalassemias in infants on birth outcomes.

OBJECTIVE: The contribution of sickle cell disease (SCD) and other common thalassemias in infants to adverse birth outcomes is under-studied. We therefore sought to compare adverse birth outcomes in infants with and without hemoglobinopathy. STUDY DESIGN: Retrospective cohort study utilizing a population-based dataset from Florida (1998-2007, n=1,564,038). The primary outcomes were low birthweight (LBW), very low birthweight (VLBW), preterm birth (PTB), very preterm birth (VPTB) and small for gestational age (SGA). We used propensity scores to match infants with hemoglobinopathy to those without hemoglobinopathy on selected variables. To approximate relative risks, we generated adjusted odds ratios (AOR) and 95% confidence intervals (CI) from logistic regression models and accounted for the matched design using generalized estimating equations framework. RESULTS: Infants with SCD or thalassemia had a heightened risk for LBW (AOR=1.58, 95% CI: 1.29-1.93), VLBW (AOR=3.01, 95% CI: 2.12-4.25), PTB (AOR=1.36, 95% CI: 1.12-1.65), VPTB (AOR=2.70, 95% CI: 1.93-3.78), and neurological conditions (AOR=2.04, 95% CI: 1.48-2.81) compared to infants without hemoglobinopathy. CONCLUSION: Infants with SCD or thalassemia experience considerably higher risks for multiple infant morbidities. Our findings are potentially important in prenatal counseling, as well as for targeted care of affected pregnancies in the prenatal period.

Cigarette smoking and fetal morbidity outcomes in a large cohort of HIV-infected mothers.

BACKGROUND: Reproductive-age women comprise approximately 25% of all persons living with HIV/AIDS in the United States. HIV infection and smoking during pregnancy are independent risk factors for adverse fetal outcomes. We examined predictors of fetal growth restriction among infants born to HIV-infected mothers who smoke cigarettes in pregnancy. METHODS: We analyzed hospital discharge data linked to birth records from the state of Florida for 1998-2007 (N = 1,645,209). The outcomes of interest included: low and very low birth weight (LBW and VLBW), preterm and very preterm birth (PTB and VPTB), and small for gestational age (SGA). We calculated adjusted rate ratios (ARR) for these outcomes by HIV/AIDS status, smoking status, and sociodemographic variables. We also examined the association between the observed fetal morbidity outcomes and the interaction between HIV/AIDS and smoking status. We employed the generalized estimating equation framework to correct for intracluster correlations. RESULTS: All fetal morbidity outcomes were more common in mothers who had HIV/AIDS, regardless of smoking status. Maternal HIV status and cigarette use were independent predictors of LBW, PTB, and SGA, with morbidity effects more prominent in HIV-infected mothers who smoke cigarettes. We observed a significant interaction between maternal HIV and smoking status, in which mothers who were HIV positive and smoked during pregnancy experienced the greatest risks for LBW (ARR = 2.24 [1.89-2.65]), SGA (ARR = 1.95 [1.67-2.29]), and PTB (ARR = 1.70 [1.42-2.03]). CONCLUSIONS: HIV-infected mothers who smoke cigarettes during pregnancy have a heightened risk for adverse fetal morbidity outcomes. There is a need for integration of smoking cessation interventions into ongoing HIV/AIDS programs.

Infant mortality and the risk of small size for gestational age in the subsequent pregnancy: a retrospective cohort study.

To examine the association between prior infant mortality and subsequent risk for small for gestational age (SGA). This population-based, retrospective cohort study used the Missouri maternally linked, longitudinal dataset (1989-2005). Analyses were restricted to women who had two singleton pregnancies during the study period. Logistic regression was conducted to obtain adjusted odds ratios (AOR) and 95 % confidence intervals (CI) for the association between infant mortality in the first pregnancy and SGA in the second pregnancy. Women with a prior occurrence of infant death were more likely to be black and obese and had lower educational levels and had higher rates of pregnancy-related complications (p < 0.01). White women with previous infant mortality were at 1.46 times greater risk for SGA in the subsequent pregnancy (AOR = 1.46, 95 % CI = 1.24-1.71). For black women with prior infant death, the risk for SGA increased to 2.77 times (AOR = 2.77, 95 % CI = 2.19-3.51). White mothers who experienced infant mortality coupled with SGA in the first pregnancy had a nearly threefold heightened risk for SGA in the second pregnancy (AOR = 2.89, 95 % CI = 2.21-3.78), whereas black women with this history were more than four times as likely to have an infant with SGA (AOR = 4.60 95 % CI = 3.05-6.96). Prior occurrence of infant mortality is associated with increased risk for subsequent SGA. This finding has important implications for health professionals, as targeted inter-conception strategies for women who have experienced infant death, as well as SGA, may be warranted.

Small size for gestational age and the risk for infant mortality in the subsequent pregnancy.

PURPOSE: To examine the association between small for gestational age (SGA) in the first pregnancy and risk for infant mortality in the second pregnancy. METHODS: This is a population-based, retrospective cohort study in which we used the Missouri maternally linked cohort dataset for 1978-2005. Analyses were restricted to women who had two singleton pregnancies during the study period. The exposure was SGA in the first pregnancy, whereas the primary outcome was infant mortality in the second pregnancy. Kaplan-Meier Estimate and Cox proportional hazard regression were conducted. RESULTS: Infant mortality was significantly greater among mothers with previous SGA (P < .01). A persistent association of previous SGA with subsequent infant mortality was observed (adjusted hazard ratio [AHR] 1.35, 95% confidence interval [95% CI] 1.24-1.48). Race-specific data illustrated that black women with a previous SGA birth were 40% more likely to experience infant mortality (AHR 1.40, 95% CI 1.21-1.63) than their counterparts without a history of SGA, but white women with a previous SGA had an increased risk of 31% (AHR 1.31, 95% CI 1.17-1.46). CONCLUSIONS: Women with previous SGA bear increased risks for subsequent infant mortality, which was greater among black mothers. Hence, SGA plays an important role in the black-white disparity in infant mortality. Women's previous childbearing experiences could serve as important criterion in determining appropriate interconception strategies to improve infant health and survival.

The association between HIV/AIDS during pregnancy and fetal growth parameters in Florida: a population based study.

In this population-based retrospective study, we sought to investigate the association between HIV/AIDS during pregnancy and adverse birth outcomes, including low birth weight (LBW), very low birth weight (VLBW), preterm birth (PTB), very preterm birth (VPTB), and small for gestational age (SGA), among women in Florida by sociodemographic variables. Using data from Florida's maternally linked birth cohort files, we examined singleton live births in the state during 1998 to 2007 (N = 1,698,107). The study population was categorized based on the maternal HIV/AIDS status. Poisson regression models were used to generate adjusted rate ratios (ARR) to estimate the association between HIV/AIDS status and fetal growth parameters. The main outcome measures were fetal growth parameters, including LBW, VLBW, PTB, VPTB, and SGA. As compared to HIV/AIDS-negative women, mothers with HIV/AIDS had elevated risks for LBW (ARR = 1.40; 95% CI = 1.30-1.50), VLBW (ARR = 1.25; 95% CI = 1.04-1.51), SGA (ARR = 1.26; 95% CI = 1.17-1.35), PTB (ARR = 1.23; 95% CI = 1.03-1.47), and VPTB (ARR = 1.27; 95% CI = 1.20-1.36). Risk estimates for LBW and SGA were highest among Hispanics mothers with HIV/AIDS, while white mothers with HIV/AIDS had the highest risk levels for VLBW and PTB, compared to their HIV/AIDS negative counterparts. Our findings show that women with HIV/AIDS have elevated risks for inhibited fetal growth and shortened gestation with important racial/ethnic variation. This is the first known population-based study that reveals racial/ethnic differences in HIV/AIDS-related fetal growth morbidity outcomes.

The effect of paternal age on fetal birth outcomes.

Research investigating the role of paternal age in adverse birth outcomes is limited. This population-based retrospective cohort study used the Missouri maternally linked data set from 1989 to 2005 to assess whether paternal age affects fetal birth outcomes: low birth weight (LBW), preterm birth (PTB), stillbirth, and small size for gestational age (SGA). We examined these outcomes among infants across seven paternal age-groups (<20, 20-24, 25-29, 30-34, 35-39, 40-45, and >45 years) using the generalized estimating equation framework. Compared with infants born to younger fathers (25-29 years), infants born to fathers aged 40 to 45 years had a 24% increased risk of stillbirth but a reduced risk of SGA. A 48% increased risk of late stillbirth was observed in infants born to advanced paternal age (>45 years). Moreover, advanced paternal age (>45 years) was observed to result in a 19%, 13%, and 29% greater risk for LBW, PTB, and VPTB (very preterm birth) infants, respectively. Infants born to fathers aged 30 to 39 years had a lower risk of LBW, PTB, and SGA, whereas those born to fathers aged 24 years or younger had an elevated likelihood of experiencing these same adverse outcomes. These findings demonstrate that paternal age influences birth outcomes and warrants further investigation.

Temporal trends in cardiomyopathy in pregnancy and association with feto-infant morbidity outcomes.

OBJECTIVE: To examine temporal trends of cardiomyopathy in pregnancy and its association with feto-infant morbidity outcomes. DESIGN AND METHODS: We performed a population-based retrospective cohort analysis utilizing the Florida hospital discharge data linked to vital statistics for 1998 to 2007 (N = 1 738 860). Prevalence rates and trend statistics of cardiomyopathy were computed. Conditional logistic regression models were used to generate adjusted odds ratios (AOR) and 95% confidence intervals (CI). RESULTS: The annual prevalence of cardiomyopathy in pregnancy increased from 8.5/100 000 births to 32.7/100 000 (p for trend <0.0001), representing an absolute increase of 24% and a relative increase of 300% over the decade. Infants born to women with cardiomyopathy were at higher risk for feto-infant morbidities, including low birth weight (AOR = 3.49, 95% CI: 2.97-4.11), very low birth weight (AOR = 4.43, 95% CI: 2.98-6.60), preterm birth (AOR = 3.33, 95% CI: 2.88-3.85), very preterm birth (AOR = 5.22, 95% CI: 3.92-6.97) and small for gestational age (AOR = 1.57, 95% CI: 1.26-1.96). CONCLUSION: The observed increasing prevalence of cardiomyopathy during pregnancy over the decade is of concern, as it is related to elevated risk for feto-infant morbidities. There is a need to delineate risk factors for this condition and to formulate appropriate preconception counseling for women with elevated risk for this diagnosis.

Maternal HIV/AIDS status and neurological outcomes in neonates: a population-based study.

This study sought to examine the association between maternal HIV/AIDS infection and neonatal neurologic conditions in the state of Florida. We analyzed all births in the state of Florida from 1998 to 2007 using hospital discharge data linked to birth certificate records. The main outcomes of interest included selected neonatal neurologic complications, namely: fetal distress, cephalohematoma, intracranial hemorrhage, seizure, feeding difficulties, and other central nervous system complications. The sample size for this study was 1,645,515 records. All forms of substance abuse as well as cesarean section deliveries were more frequent in mothers with HIV/AIDS. Infants born to HIV-infected mothers showed higher proportions of feeding difficulties and seizures whereas HIV-negative mothers had a greater proportion of cases of fetal distress and cephalohematoma. Seizures and feeding difficulties are common among infants born to HIV/AIDS infected mothers. This population-based retrospective cohort study provides further understanding of the association between maternal HIV/AIDS status and neonatal neurological outcomes.

Neonatal outcomes of successful VBAC among obese and super-obese mothers.

OBJECTIVE: We sought to evaluate neonatal morbidity and mortality among women who experienced successful vaginal births after previous cesarean delivery (VBAC) by obesity subtypes. METHODS: Missouri maternally linked cohort data files were utilized. Analyses were restricted to successful singleton VBACs. Main study outcomes were neonatal death and neonatal morbidity. Risk estimates were obtained using logistic and hazards regression modeling. RESULTS: A total of 30,017 singleton births met inclusion criteria. The prevalence of VBAC was 2.3%. The neonatal death rate (per 1000) by maternal obesity subtype was 4.1 for moderate, 3.2 for severe, 4.5 for extreme and 14.3 for super-obese. The overall risk for neonatal morbidity was 56% greater among obese women when compared with normal weight women, with risk estimates increased incrementally with ascending body mass index (BMI) (p for trend < 0.01). CONCLUSION: Infants of obese women undergoing successful VBAC are at elevated risk for neonatal morbidity, and the risk increases progressively with ascending BMI.

Prevalence and temporal trends of hepatitis B, hepatitis C, and HIV/AIDS co-infection during pregnancy across the decade, 1998-2007.

BACKGROUND: Limited data are available on hepatitis rates during pregnancy by socio-demographic characteristics. This study examined temporal trends in hepatitis B virus (HBV) and hepatitis C virus (HCV) mono-infections and HIV/HBV and HIV/HCV co-infections in subpopulations among pregnant women in Florida between 1998 and 2007. METHODS: We analyzed all Florida live births from 1998 to 2007 using hospital discharge data linked to birth records. RESULTS: The total sample size was 1,700,734 singleton live births. The prevalance of HBV in pregnancy rose from 65.4 per 100,000 births to 123.5 per 100,000 births (p<0.0001 for trend), and the prevalence of HCV in pregnancy increased from 17.0 per 100,000 births to 125.1 per 100,000 births (p<0.0001 for trend). Compared with white mothers, black mothers were more than twice as likely to have HBV in pregnancy (adjusted rate ratios [ARR]=2.24; 95% CI=1.97-2.53). Black mothers were 69% (ARR=0.31, 95% CI=0.25-0.39) and Hispanic mothers were 51% (ARR=0.49, 95% CI=0.41-0.60) less likely to have HCV compared with white mothers. CONCLUSIONS: Although the overall prevalence rate of HBV increased over the past decade, black women still had a noticeably higher rate of infection. Similarly, white women and those with HIV co-infection had noticeably higher rates of HCV infection over the study period. Our findings call for improved and increased HBV/HCV prevention, screening, and immunization programs among minority women of childbearing age.

Impact of prior bariatric surgery on maternal and fetal outcomes among obese and non-obese mothers.

PURPOSE: To assess the association between bariatric surgery and pregnancy-related outcomes among obese and non-obese women in the state of Florida. METHODS: We conducted a population-based, retrospective cohort analysis using vital records and hospital discharge data in Florida during 2004-2007. Women were categorized based on prior bariatric surgery and pre-pregnancy obesity status. Maternal complications (i.e., anemia, pre-eclampsia, gestational diabetes, chronic hypertension, endocrine disorders, cesarean section, prolonged hospital stay) and fetal morbidities [macrosomia, preterm birth, small for gestational age (SGA)] were the outcomes of interest. Adjusted odds ratios (AOR) and 95% confidence intervals (CI) were computed. RESULTS: Mothers with a prior history of bariatric surgery, regardless of obesity status, were more likely to have anemia, chronic hypertension, endocrine disorders, and SGA infants. Classification based on prior history of bariatric surgery and obesity status showed that non-obese mothers with prior bariatric surgery were more likely to have anemia, chronic hypertension, endocrine disorders, and SGA infants, whereas obese mothers without prior bariatric surgery were at greater risk of having gestational diabetes, chronic hypertension, macrosomic infants (AOR = 1.69, 95% CI = 1.65-1.73), and prolonged hospital stay as compared to non-obese mother without prior bariatric surgery. CONCLUSIONS: Although prior bariatric surgery is associated with multiple negative maternal and fetal outcomes, it is protective against infant macrosomia in obese mothers. Our findings support the need for preconception/interconception services tailored for former bariatric surgery patients to improve maternal and feto-infant health outcomes.

Maternal hepatitis B and hepatitis C carrier status and perinatal outcomes.

BACKGROUND AND AIMS: To examine the association between maternal hepatitis B and C mono- and co-infections with singleton pregnancy outcomes in the state of Florida. METHODS: We analysed all Florida births from 1998 to 2007 using birth certificate records linked to hospital discharge data. The main outcomes of interest were selected pregnancy outcomes including preterm birth, low birth weight (LBW), small for gestational age (SGA), fetal distress, neonatal jaundice and congenital anomaly. RESULTS: The study sample consisted of 1,670,369 records. Human immunodeficiency virus co-infection and all forms of substance abuse were more frequent in mothers with hepatitis B and C infection. After using multivariable modelling to adjust for important socio-demographical variables and obstetric complications, women with hepatitis C infection were more likely to have infants born preterm [odds ratio (OR), 1.40; 95% confidence intervals (CI), 1.15-1.72], with LBW (OR, 1.39; 95% CI, 1.11-1.74) and congenital anomaly (OR, 1.55; 95% CI, 1.14-2.11). In addition, women with hepatitis B infection were less likely to have infants born SGA (OR, 0.79; 95% CI, 0.66-0.95). CONCLUSIONS: Our findings provide further understanding of the association between maternal hepatitis B or C carrier status and perinatal outcomes. Infants born to women with hepatitis C infection appear to be at risk for poor birth outcomes, including preterm birth, LBW and congenital anomaly.

Stillbirth as a risk factor for subsequent infant mortality.

BACKGROUND: Infant mortality is an important indicator of the health and wellness of a society. Multiple risk factors for infant mortality have been identified and investigated; however, the influence of prior pregnancy experience on subsequent infant mortality is under-researched. AIMS: To examine the association between stillbirth in the first pregnancy and risk for infant mortality in the second pregnancy in a large population-based dataset. STUDY DESIGN: Population-based, retrospective cohort study SUBJECTS: Missouri maternally linked cohort data files were utilized from 1989 through 2005. Analyses were restricted to women who had two singleton pregnancies during the study period. OUTCOME MEASURES: The exposure was stillbirth in the first pregnancy, while the primary outcome was infant mortality in the second pregnancy. RESULTS: Women who experienced stillbirth in their first pregnancy were more likely to be of advanced age, black, and obese and had higher rates of pregnancy-related complications (p<0.01). Previous stillbirth was associated with an elevated risk for subsequent infant mortality (AHR=2.51, 95% CI: 1.73-3.65) and neonatal mortality (AHR=3.04, 95% CI: 1.99-4.65), after adjustment for socio-demographic variables and pregnancy complications. Risk estimates for mortality in the second pregnancy were most profound among black mothers with a history of stillbirth in the first pregnancy [risk for infant mortality: (AHR=2.68, 95% CI: 1.41-5.09) and neonatal death: (AHR=4.25, 95% CI: 2.34-7.60)]. CONCLUSIONS: Women with prior stillbirth bear elevated risks for subsequent infant mortality. Women's previous childbearing experiences could serve as important criteria in determining appropriate interconception strategies to improve subsequent feto-infant health and survival.

The impact of obesity on maternal morbidity and feto-infant outcomes among macrosomic infants.

OBJECTIVE: To estimate the contribution of obesity to maternal complications, neonatal morbidity and mortality among macrosomic births. DESIGN: A population-based retrospective cohort design using State of Missouri maternally linked birth cohort files. METHODS: Using pre-gravid body mass index (BMI), we categorized mothers of 116,976 singleton macrosomic live births as non-obese (BMI < 30) or obese (BMI ≥ 30). We used logistic regression models to generate adjusted odd ratios for pregnancy and neonatal complications. We also estimated the proportion of potentially preventable excess maternal and neonatal complications that could be eliminated among obese women with infant macrosomia at various levels of pre-pregnancy obesity reduction. RESULT: Obese mothers with macrosomic infants were at elevated risk for chronic hypertension (odds ratio (OR) = 6.78 [95% confidence interval (CI): 5.82-7.88]), insulin-dependent diabetes mellitus, (OR = 2.60 [CI: 2.34-2.88]) other types of diabetes mellitus (OR = 2.83 [CI: 2.65-3.02]) and preeclampsia (OR = 2.49 [CI: 2.33-2.67]). Macrosomic infants of obese mothers were at greater risk for hyaline membrane disease (OR = 2.14 [CI: 1.73-2.66]), extended assisted ventilation (OR = 1.71 [CI: 1.44-2.04]), birth injury (OR = 1.58 [CI: 1.37-1.84]) and meconium aspiration syndrome (OR = 1.42 [CI: 1.09-1.87]). The proportion of preventable excess maternal morbidity was 60%, 45%, 30% and 15%, assuming an effective pre-conception intervention that could reduce obesity down to 0%, 25%, 50% and 75% of its current level, respectively. The corresponding proportion of preventable excess neonatal complications would be 40%, 30%, 20% and 10%, respectively. CONCLUSION: Among obese mothers with macrosomic births, a substantial proportion of maternal and neonatal morbidity could be averted through effective pre-conception interventions.