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Barbara Luke

Publications and source records attributed to Barbara Luke.

At least 19 recordsLinked to original sources
PubMed2006

Is antiretroviral therapy during pregnancy associated with an increased risk of preterm delivery, low birth weight, or stillbirth?

BACKGROUND: Data on complications of pregnancy associated with antiretroviral therapy are limited. Some small studies have demonstrated an increased preterm delivery rate, but a recent retrospective United States multisite study did not concur with these findings. Our objective was to investigate whether antiretroviral therapy was associated with adverse pregnancy outcome at a single site. METHODS: Using prospectively gathered data, women were identified who were determined to be human immunodeficiency virus positive before or during pregnancy who sought care at our prenatal clinic and who gave birth at the University of Miami/Jackson Memorial Medical Center from 1990 through 2002. The outcome measures were preterm delivery, low birth weight, and stillbirth. RESULTS: The cohort included 999 women who received antiretroviral therapy during pregnancy (monotherapy in 492, combination therapy without a protease inhibitor [PI] in 373, and combination therapy with a PI in 134) and 338 women who did not receive therapy. After adjustment for possible confounders, only combination therapy with a PI was associated with an increased risk of preterm delivery, compared with any other combination (odds ratio, 1.8 [95% confidence interval, 1.1-3.0]). There were no differences in rates of low birth weight and stillbirth, regardless of therapy. CONCLUSION: Compared with monotherapy and combination therapy without a PI, only combination therapy with a PI was associated with an increased risk of preterm delivery.

Adolescent↗
PubMed2006

Perinatal and early childhood outcomes of twins versus triplets.

The purpose of this prospective cohort study of twins and triplets was to evaluate perinatal and early childhood outcomes through 18 months of age. The study population included 141 twin pregnancies (282 twin children) and 8 triplet pregnancies (24 triplet children) recruited between May, 1996 and June, 2001. Mothers of triplets versus twins were significantly more likely to have infertility treatments, to be overweight or obese before conception, to be admitted antenatally, and to deliver by cesarean section. Length of gestation for triplets was significantly shorter (-2.31 weeks, p < .0001), and more likely to be less than 35 weeks (Adjusted Odds Ratio [AOR] 9.38, 95% confidence interval [CI] 3.22-27.29). Average birthweight for triplets was significantly lighter (-495 grams, p < .0001), and more likely to be low birthweight (AOR 11.38, 95% CI 3.11-41.61). Triplets were also more likely to be admitted to neonatal intensive care (AOR 7.97, 95% CI 2.13-29.77), to require mechanical ventilation (AOR 5.67, 95% CI 2.05-15.65), to develop respiratory distress syndrome (AOR 12.50, 95% CI 3.89-40.20), or a major morbidity (retinopathy of prematurity, necrotizing enterocolitis, ventilator support, or grade III or IV intraventricular hemorrhage, AOR 5.67, 95% CI 2.05-15.65). Weight, length, and head circumference was significantly smaller at birth for triplets compared to twins, and these differences remained through 18 months of age, along with lower mental developmental scores at the oldest age. Compared to twins, triplets have greater neonatal morbidity, and through 18 months of age lower mental and motor scores, slower postnatal growth and more residual stunting, particularly of length and head circumference.

Chi-Square Distribution↗
PubMed2006

The changing risk of infant mortality by gestation, plurality, and race: 1989-1991 versus 1999-2001.

OBJECTIVE: Our aim was to quantify contemporary infant mortality risks and to evaluate the change by plurality, gestation, and race during the most recent decade. PATIENTS AND METHODS: The study population included live births of 20 to 43 weeks' gestation from the 1989-1991 and 1999-2001 US Birth Cohort Linked Birth/Infant Death Data Sets, including 11,317,895 and 11,181,095 live births and 89,823 and 67,129 infant deaths, respectively. Adjusted odds ratios and 95% confidence intervals were calculated to evaluate the change in risk by plurality and gestation and to compare the change with that for singletons. RESULTS: Overall, the infant mortality risk decreased significantly for singletons, twins, and triplets but nonsignificantly for quadruplets and quintuplets. Compared with singletons, significantly greater reductions were experienced by twins overall and at <37 weeks and triplets at <29 weeks. The largest reduction was for triplets at 20 to 24 weeks and for quadruplets and quintuplets at 25 to 28 weeks. For white infants, significant reductions were achieved overall for singletons, twins, and triplets and at every gestation. For black infants, significant reductions occurred for singletons overall and at every gestation, for twins at <37 weeks, and for triplets at 25 to 28 weeks. Compared with white infants, black infants had significantly lower risks before and higher risks after 33 weeks, although between 1989-1991 and 1999-2001 this survival advantage at earlier ages diminished, and the risk at later gestations increased. CONCLUSIONS: The improvements in survival were greater for multiples versus singletons and for white versus black infants. Within each plurality, at each gestation the racial disparity in mortality has widened.

Adult↗
PubMed2006

Outcome of pregnancies among Hispanics: revisiting the epidemiologic paradox.

OBJECTIVE: To evaluate the outcome of pregnancies among Hispanics in a tertiary care hospital in Miami, Florida. STUDY DESIGN: Retrospective study of all women who delivered in our institution over an 11-year period. Outcome variables were stratified by race/ethnicity groups: Hispanics, non-Hispanic blacks and non-Hispanic whites. Variables included rates of low birth weight (LBW), preterm delivery (PTD) and other selected pregnancy outcomes. RESULTS: Thirty-five percent were of Hispanic origin, mainly of Caribbean, Central American and South American origin. Hispanics had the lowest rate of LBW (9%) when compared to blacks, non-Hispanics (18%) and white non-Hispanics (11%) (p < 0.0001). Hispanic women were less likely to deliver prematurely, at < 37 weeks (adjusted odds ratio [AOR] 0.68, 95% CI 0.65-0.91, p < 0.0001), < 32 weeks (AOR 0.57, 95% CI 0.52-0.63, p < 0.0001) and < 28 weeks (AOR 0.66, 95% CI 0.51-0.65, p < 0.0001). Hispanic women were less likely to have preterm premature rupture of membranes (AOR 0.66, 95% CI 0.58-0.75, p < 0.0001). CONCLUSION: Hispanics have the lowest PTD and LBW rates when compared to non-Hispanic whites and blacks.

Adult↗
PubMed2005

The cost of twin pregnancy: maternal and neonatal factors.

OBJECTIVE: The purpose of this study was to evaluate factors affecting birth charges in twin pregnancies. STUDY DESIGN: Clinical and financial data were obtained on 1486 twin pregnancies delivered between 1995 to 2002 at medical centers in Maryland, Florida, Michigan, and South Carolina. Maternal and neonatal length of stay (LOS) and charges were modeled by gestational age and other risk factors using a general linear model. RESULTS: Maternal and infant birth admission LOS and charges increased significantly with a decline in gestational age. Maternal LOS and charges were also significantly increased by cesarean delivery and preeclampsia. Newborn LOS and charges increased significantly by monochorionicity and slowed growth between 20 to 28 weeks. For mother and infants, the shortest LOS and lowest birth charges were at 37 to 38 weeks. CONCLUSION: These findings reflect the substantial maternal and neonatal morbidity associated with twin pregnancies, and demonstrate that 37 to 38 weeks is their optimal gestation.

Adolescent↗
PubMed2005

Fetal growth rates and the very preterm delivery of twins.

OBJECTIVE: Our objective was to determine whether slow fetal growth rates and twin growth patterns from 20 weeks' gestation to delivery are associated with very preterm delivery. STUDY DESIGN: Available charts were reviewed for twin pregnancies, delivered between 1979 and 2002, at 4 U.S. medical centers. The sample of 1612 pregnancies delivered at 28 week's gestation or greater and had at least 2 ultrasound evaluations of fetal size from 20 to 28 weeks or from 28 weeks to delivery for estimation of fetal growth rates (grams per week). Slow fetal growth (below the 10th percentile) was defined as less than 90 grams per week at 20-28 weeks and 168 g/week from 28 weeks to delivery. The main outcome measure was the timing of delivery. RESULTS: Of the women delivering twins, 5.3% delivered extremely preterm (28-30 weeks), 8.5% very preterm (31-32 weeks), and 40.1% preterm (33-36 weeks). Patterns of growth for the pair were highly associated with very preterm delivery. Compared with neither growing slowly (1.7%), 4.9% delivered very preterm if only 1 twin grew slowly. Very preterm was 14.6% (adjusted odds ratio 9.81; 95% confidence interval, 3.50-27.48) with both growing slowly from 28 weeks on and 20.0% (adjusted odds ratio 15.04; 95% confidence interval 5.13-44.11) with both growing slowly over both intervals. Survival analyses indicated that twins with normal growth in both intervals remained undelivered for a significantly longer number of days (P < .0001) than pairs in which one or both twins were growing slowly. CONCLUSION: Very preterm delivery of twins seems to be preceded by slowed or compromised fetal growth for the pair.

Diseases in Twins↗
PubMed2005

Nutrition in multiple gestations.

Multiple pregnancies represent a state of magnified nutritional requirements, resulting in a greater nutrient drain on maternal resources and an accelerated depletion of nutritional reserves. Maternal weight gain to 20 weeks and between 20 and 28 weeks has the greatest effect on birthweight in twin and triplet pregnancies, particularly among underweight women. Parity, which most likely represents a higher proportion of body fat, has a positive effect on pregnancy outcome, with an average 7 to 10 days longer gestation for multiparous versus nulliparous women. In addition to being the nutrients most often lacking in a woman's diet, calcium, magnesium, and zinc have been identified as having the most potential for reducing pregnancy complications and improving outcomes.

Female↗
PubMed2005

Nutrition and multiple gestation.

Multiple pregnancy represents a state of magnified nutritional requirements, resulting in a greater nutrient drain on maternal resources and an accelerated depletion of nutritional reserves. The accelerated starvation which occurs in pregnancy is exaggerated with a multiple gestation, particularly during the second half of pregnancy, with more rapid depletion of glycogen stores and resultant metabolism of fat between meals and during an overnight fast. A reduced glucose stream from mother to fetus results in slower fetal growth, smaller birth size, as well as a higher risk of preterm labor and preterm birth. For this reason, diet therapy with a diabetic regimen of 20% of calories from protein, 40% of calories from carbohydrate, and 40% of calories from fat may be particularly useful. Iron-deficiency anemia has also been linked to preterm delivery and other adverse pregnancy outcomes. Mobilization of maternal iron stores, in addition to an adequate amount and pattern of gestational weight gain (including BMI-specific weight gain goals by 20 and 28 weeks gestation), has been associated with significantly better fetal growth and longer gestations in twin pregnancies. Supplementation with calcium, magnesium, and zinc, as well as multivitamins and essential fatty acids may also reduce pregnancy complications and improve postnatal health for infants born from a multiple gestation. Diet therapy for women pregnant with multiples is an important component of effective prenatal care.

Diet↗
PubMed2005

Gender mix in twins and fetal growth, length of gestation and adult cancer risk.

This study evaluated the effect of gender mix (the gender combinations of twin pairs) on fetal growth and length of gestation, and reviewed the literature on the long-term effects of this altered fetal milieu on cancer risk. In singletons, it is well established that females weigh less than males at all gestations, averaging 125-135 g less at full term. This gender difference is generally believed to be the result of the effect of androgens on fetal growth. The gender difference in fetal growth is greater before the third trimester and less towards term, with males growing not only more, but also earlier than females. Plurality is a known risk factor for reduced fetal growth and birthweight. Compared with singletons, the mean birthweight percentiles of twins fall substantially (by 10% or more) below the singleton 10th percentile by 28 weeks, below the singleton 50th percentile by 30 weeks, and below the singleton 90th percentile by 34 weeks. In unlike-gender twin pairs, it has been reported that the female prolongs gestation for her brother, resulting in a higher birthweight for the male twin than that of like-gender male twins. Other researchers have demonstrated that females in unlike-gender pairs had higher birthweights than females in like-gender pairs. Analyses from our consortium on 2491 twin pregnancies with known chorionicity showed longer gestations and faster rates of fetal growth in both males and females in unlike-gender pairs compared with like-gender male or female pairs, although these differences were not statistically significant. The post-natal effects for females growing in an androgenic-anabolic environment include increased sensation-seeking behaviour and aggression, lowered visual acuity, more masculine attitudes and masculinising effects of the auditory system and craniofacial growth. In contrast, there is no evidence to suggest that there might be a similar feminising effect on males from unlike-gender pairs. This hormonal exposure in utero may influence adult body size and susceptability to breast cancer.

Adult↗
PubMed2005

Midupper arm circumference (MUAC) changes in late pregnancy predict fetal growth in twins.

The objective of the study was to test the hypothesis that changes in arm anthropometry can be used to determine the risk of faltering growth in twin gestations. Serial data on midupper arm circumference (MUAC) and maternal weight gain were collected from a sample of 156 mothers. Changes in MUAC were monitored from 20 to 34 weeks. Women with a large loss of MUAC (greater than 1.5 cm), particularly when it occurred within two to four weeks of delivery, were significantly heavier, had higher pregravid Body Mass Indexes (BMIs), but gained less weight than mothers with no change in MUAC. In analysis of covariance models adjusting for length of gestation, black ethnicity, males per twin pair, monochorionicity, and baseline MUAC at 20 weeks, a large loss of MUAC was associated with significantly lower birthweight (2263 g vs. 2499 g) and birthweight z-score (-0.92 SDU vs. -0.39 SDU). Changes in MUAC from 20 to 34 weeks, and especially near delivery, are significantly associated with fetal growth in twin pregnancies. A positive change may indicate that the mother has adequate dietary intake or nutrient stores to continue to accrue lean body mass and support fetal growth, while a loss of MUAC indicates that dietary intake or nutrient stores may be inadequate. This simple, relatively precise, measure of change in maternal body composition during pregnancy may be useful in identifying twin pregnancies at risk for faltering intrauterine growth, particularly among overweight or obese women.

Adult↗
PubMed2005

The Hispanic paradox in twin pregnancies.

The objective of this study was to compare length of gestation, fetal growth, and birthweight by race/ethnicity and pregravid weight groups in twin pregnancies. Three thousand and thirty-six twin pregnancies of 28 weeks or more gestation were divided by race/ethnicity (White, Black and Hispanic), and pregravid body mass index (BMI) groups (less than 25.0 vs. 25.0 or more). Outcomes were modeled using multiple regression, controlling for confounders, with White non-Hispanic women as the reference group. Hispanic women had the highest average birthweight and the longest gestation, as well as the lowest proportions of low birthweight, very low birthweight, preterm and early preterm births of the 3 race/ethnicity groups. In the multivariate analyses, Hispanic women had significantly longer gestations (by 7.8 days) and faster rates of fetal growth midgestation (20 to 28 weeks, by 17.4 g/week) and late gestation (after 28 weeks, by 5.3 g/week), whereas Black women had significantly slower rates of fetal growth (by 5.7 g/week and by 4.5 g/week, respectively). These findings in twins reflect the racial and ethnic disparities previously shown in singletons, including the Hispanic paradox of longer gestations and higher rates of fetal growth.

Birth Weight↗
PubMed2005

The evidence linking maternal nutrition and prematurity.

Maternal nutrition may be one of the most important under-evaluated factors contributing to the contemporary rise in prematurity in the United States and other industrialized nations around the world. Slowed fetal growth has been repeatedly shown to be associated with preterm birth, in both singleton and twin pregnancies. Antecedents of impaired fetal growth include a wide variety of factors, including intergenerational effects, biological and social factors related to race and ethnicity, maternal pregravid weight and gestational weight gain, and iron and mineral status. An assessment of maternal nutritional status, including anthropometric factors, is an integral component of effective prenatal care, and may facilitate a reduction in prematurity.

Calcium↗
PubMed2005

Elevated maternal glucose concentrations and placental infection in twin pregnancies.

OBJECTIVE: To evaluate the association between maternal screening glucose concentration and placental infection in nondiabetic twin pregnancies. STUDY DESIGN: One thousand sixty-one nondiabetic twin pregnancies at > or =28 weeks' gestation were divided into 3 groups based on the screening 50-g fasting glucose concentration at 24-28 weeks: lowest quartile (< 96 mg/dL), middle 2 quartiles (96-128 mg/dL) and upper quartile (> 128 mg/dL). Outcomes were modeled using general linear and multinomial logistic regression, controlling for confounding factors. RESULTS: The middle and highest glucose groups were associated with increased risks for clinical chorioamnionitis (adjusted OR [AOR] 3.18, 95% CI 1.34, 7.54; AOR 6.80, CI 1.89, 24.53, respectively). Birth at <32 weeks and histologic diagnosis of placental infection (chorioamnionitis, funisitis, necrosis, vasculitis or villitis) were significantly associated only with the highest glucose group (AOR 1.79, CI 1.02, 3.13; AOR 6.95, CI 1.10, 8.68, respectively). CONCLUSION: Elevated screening glucose in nondiabetic twin pregnancies may be a marker of placental inflammation and infection.

Adult↗
PubMed2004

Fetal phenotypes and neonatal and early childhood outcomes in twins.

OBJECTIVES: The purpose of this study was to evaluate factors associated with, and postnatal consequences of, altered patterns of fetal growth in twins. STUDY DESIGN: Fetal growth was measured at 28 weeks' gestation on 218 twins, including head circumference, abdominal circumference, and femur length, and characterized as > or < or =10th %ile; children were followed up until the age of three years. Logistic regression was used to generate odds ratios of perinatal factors associated with reduced fetal growth. RESULTS: Maternal height <62 inches was associated with reductions in femur length (adjusted odds ratio [AOR] 3.88, 95% CI 1.42-10.57) and abdominal circumference (AOR 8.63, 95% CI 2.41-30.94), while primiparity had a protective effect on both of these fetal measurements (AOR 0.28, 95% CI 0.13-0.64, and AOR 0.18, 95% CI 0.06-0.60, respectively), as well as head circumference (AOR 0.32, 95% CI 0.15-0.69). Smoking adversely affected femur and head growth (AOR 24.10, 95% CI 3.69-157.57, and AOR 10.82, 95% CI 1.73-67.79, respectively). Fetal reduction adversely affected femur and abdomen growth (AOR 5.85, 95% CI 1.52-22.51 and AOR 4.90, 95% CI 1.01-23.86, respectively), and monochorionicity and maternal weight gain <0.65 lb/wk before 20 weeks adversely affected femur growth (AOR 5.47, 95% CI 1.65-18.10, and AOR 3.39, 95% CI 1.34-8.59, respectively). At age 3 years, all categories of twins with reduced growth by 28 weeks' gestation were significantly shorter in height, and those with reduced abdominal circumference or head circumference at 28 weeks were also significantly lighter in weight compared with twins with adequate fetal growth by 28 weeks' gestation. CONCLUSION: These data identify short maternal height, smoking, monochorionicity, fetal reduction, and inadequate weight gain before 20 weeks as risk factors associated with reduced twin fetal growth by 28 weeks' gestation and significant residual reductions in height and weight through 3 years of age.

Body Height↗
PubMed2004

Risk factors for adverse outcomes in spontaneous versus assisted conception twin pregnancies.

OBJECTIVE: To evaluate risk factors for adverse outcomes in spontaneous vs. assisted conception twin pregnancies. DESIGN: Historical cohort study. SETTING: Four academic tertiary medical centers. PATIENT(S): Women with twin pregnancies, including 2,143 spontaneous and 424 assisted conception; 2,492 nonreduced and 75 reduced. INTERVENTION(S): None (observational). MAIN OUTCOME MEASURE(S): Preeclampsia, preterm premature rupture of membranes, birth <32 weeks and <30 weeks, low birth weight, very low birth weight, and slowed midgestation fetal growth (<10th percentile between 20 and 28 weeks). RESULT(S): Among nonreduced pregnancies, assisted conception was not significantly associated with any adverse outcomes; among nulliparas, the risk for preeclampsia was increased regardless of method of conception; among spontaneous conceptions, the risks for preterm premature rupture of membranes, low birth weight, very low birth weight, and slowed midgestation fetal growth were increased. Among all pregnancies, fetal reduction increased risks for birth <32 weeks and <30 weeks, low birth weight, very low birth weight, and slowed midgestation fetal growth. Among nulliparas with assisted conceptions, fetal reduction increased the risks for birth <30 weeks, very low birth weight, and slowed midgestation fetal growth. CONCLUSION(S): These findings indicate that in twin pregnancies, assisted conception is not a risk factor for adverse outcomes, but rather specific factors that are more common among these pregnancies, such as nulliparity and fetal reduction, increase risks.

Adult↗
PubMed2003

Antenatal factors associated with significant birth weight discordancy in twin gestations.

OBJECTIVE: The purpose of this study was to evaluate factors that are associated with significant birth weight discordancy. STUDY DESIGN: As a part of an ongoing collaborative study of twins, maternal and fetal data were obtained from the medical records of twin gestations at eight medical centers. The study population was divided into groups by difference in birth weight discordancy (>or=20%, >or=25%, and >or=30%) RESULTS: Severe birth weight discordancy was associated with fetal growth deceleration by 20 to 28 weeks (adjusted odds ratio, 4.90; 95% CI, 3.15-7.64) and between 28 weeks to birth (adjusted odds ratio, 3.48; 95% CI, 1.72-7.06). Antenatal bleeding (adjusted odds ratio, 1.86; 95% CI, 1.08-3.21), preeclampsia (adjusted odds ratio, 1.70, 95% CI, 1.21-2.41), and monochorionicity (adjusted odds ratio, 2.35, 95% CI, 11.71-3.23) were also associated with birth weight discordancy. CONCLUSION: These data demonstrate the importance of the early diagnosis of placental chorionicity, because monochorionicity is associated with a 2-fold increase in birth weight discordancy in twin gestations.

Adult↗