Gestational diabetes mellitus screening using the one-step versus two-step method in a high-risk practice.

Screening for gestational diabetes mellitus is controversial. In their high-risk obstetrical practice, the authors did not find a difference in delivery or neonatal outcomes when using a one-step versus a two-step screening process. They did find lower rates of compliance with screening when using the one-step method.

Perinatal and neonatal outcomes of triplet gestations based on placental chorionicity.

The purpose of our study was to evaluate perinatal and neonatal outcomes in triplet gestations in relation to placental chorionicity. We hypothesized that triplets containing a monochorionic pair (dichorionic triamniotic) would have increased morbidity compared with triplets without a monochorionic pair (trichorionic triamniotic). We retrospectively analyzed all triplet sets > or =20 weeks delivering at our institutions from January 1995 through April 2007. Data were collected via perinatal and neonatal databases, chart review, and placental pathology. Individuals in dichorionic triamniotic triplet sets (N = 75), when compared with trichorionic triamniotic triplets (N = 309), were more likely to have a lower mean birth weight (P < 0.001) and lower gestational age at delivery (P < 0.001), spend more days in the neonatal intensive care unit (P = 0.045), have culture-proven sepsis (P = 0.02), and require intubation (P = 0.05). Multivariate analysis demonstrated that dichorionicity is not an independent cause of morbidity, but results in earlier delivery and lower birth weight. Dichorionic triamniotic triplets are at increased risk for earlier deliveries and lower birth weight at delivery compared with trichorionic triamniotic triplets.

Betamethasone vs dexamethasone for the prevention of morbidity in very-low-birthweight neonates.

OBJECTIVE: The purpose of this study was to compare neonatal outcomes in very-low-birthweight infants who were exposed to antenatal betamethasone vs dexamethasone. STUDY DESIGN: We reviewed all inborn very-low-birthweight infants from January 1997 through February 2006. Maternal medical records were reviewed to determine the type of antenatal steroids that each patient received; neonatal outcomes were compared using chi-square and Student t tests. RESULTS: There were 334 very-low-birthweight infants who met the criteria for evaluation: 186 infants received betamethasone, and 148 infants received dexamethasone. There were no differences in race, gestational age at delivery, or mean birthweight between the 2 groups. There were significantly lower rates of respiratory distress syndrome and bronchopulmonary dysplasia in the betamethasone group, compared with the dexamethasone group. Other neonatal outcomes were similar in both groups. CONCLUSION: Antenatal betamethasone was associated with a significantly lower rate of pulmonary complications caused by prematurity, when compared with dexamethasone.

Toxoplasmosis, Parvovirus, and Cytomegalovirus in Pregnancy.

There are several infections in adults that warrant special consideration in pregnant women given the potential fetal consequences. Among these are toxoplasmosis, parvovirus B19, and cytomegalovirus. These infections have an important impact on the developing fetus, depending on the timing of infection. This article reviews the modes of transmission as well as maternal and neonatal effects of each of these infections. In addition, the article outlines recommended testing, fetal surveillance, and treatment where indicated.

Frequency of echogenic intracardiac focus by race/ethnicity in euploid fetuses.

OBJECTIVE: To determine the frequency of echogenic intracardiac focus (EIF) by race/ethnicity. METHODS: We performed a retrospective analysis from January 1996 through June 2003. We reviewed all initial sonograms from 14 to 23 weeks gestation in singleton pregnancies. Mothers on admission for delivery provided race/ethnicity. RESULTS: There were 8207 ultrasounds and deliveries that met study criteria. There were 4636 (56.5%) Caucasian, 2087 (25.4%) African-American, 1261 (15.4%) Hispanic and 223 (2.7 %) Asian subjects. There were 347 (4.2%) EIF detected. The frequency by race/ethnicity varied significantly (p < 0.0001). CONCLUSIONS: This large, population-based study showed that fetuses born to Asian mothers were significantly more likely to have an EIF. This racial difference should be taken into account when counseling patients about the potential for Down syndrome.

Combined second-trimester biochemical and ultrasound screening for Down syndrome.

OBJECTIVE: To evaluate the efficacy of a Down syndrome screening protocol that combines second-trimester maternal serum analytes and the continuous ultrasound measures of nuchal fold thickness and proximal long bone length. METHODS: Ultrasound measurements of nuchal fold, femur length, and humerus length were reviewed for 72 second-trimester Down syndrome and 7063 unaffected fetuses. Derived statistical variables for these parameters were entered into a multivariable Gaussian model together with the statistical variables used in the "quad" test (maternal serum alpha-fetoprotein, unconjugated estriol, human chorionic gonadotropin, and inhibin A). Maternal age-specific sensitivities, false-positive rates, and positive predictive values were generated together with receiver operating characteristic curves. Overall efficacy of ultrasound screening alone, the quad test, and the combination of the ultrasound and quad test were compared using a 1:270 second-trimester risk cutoff applied to 1999 US births. RESULTS: Using ultrasound, a sensitivity of 79.9% and false-positive rate of 6.7% may be achieved (positive predictive value: 1 in 42). The quad test has a sensitivity of 81.5% and false-positive rate of 6.9% (positive predictive value: 1 in 42). The combination of the quad test with nuchal fold and long bone measurements may achieve 90% sensitivity and a 3.1% false-positive rate (positive predictive value: 1 in 18). CONCLUSION: Combining second-trimester serum testing and fetal biometry is a feasible approach to Down syndrome screening, compatible with current obstetric practice. This modality is substantially more effective than either serum screening or ultrasound alone. Efficacy may be comparable to that reported for combined first- and second-trimester (integrated) screening.

Multiple gestations: the importance of ultrasound.

The use of ultrasound in the diagnosis of twins, its role of determining chorionicity, the management of unique twin complications, the value of cervical length determination in twins, the use of ultrasound in screening for aneuploidy in multiples, and the intrapartum role of ultrasound in twin gestations have been reviewed. The availability of high-resolution ultrasound has significantly im-proved the management of multiple gestations.

Anemia in pregnancy.

Hemodynamic changes occur in pregnancy to prepare for expected blood loss at delivery. Physiologic anemia occurs in pregnancy because plasma volume increases more quickly than red cell mass. Anemia is most commonly classified as microcytic, normocytic, or macrocytic. Iron deficiency anemia accounts for 75% of all anemias in pregnancy. Oral iron supplementation is the recommended treatment of iron deficiency anemia in pregnancy. Parenteral iron and erythropoietin can also be used in severe or refractory cases. Outcomes and treatments for other forms of inherited and acquired anemias in pregnancy vary by disease, and include nutritional supplementation, corticosteroids, supportive transfusions, and splenectomy.

Toxoplasmosis, parvovirus, and cytomegalovirus in pregnancy.

Several infections in adults warrant special consideration in pregnant women given the potential fetal consequences. Among these are toxoplasmosis, parvovirus B19, and cytomegalovirus. These infections have an important effect on the developing fetus depending on the timing of infection. This article reviews the modes of transmission as well as maternal and neonatal effects of each of these infections. In addition, recommended testing, fetal surveillance, and treatment where indicated are outlined.

Variation of fetal nasal bone length in second-trimester fetuses according to race and ethnicity.

OBJECTIVE: The purpose of this study was to determine the influence of race and ethnicity on the expected nasal bone length (NBL) based on biparietal diameter (BPD) measured in second-trimester fetuses. METHODS: We searched our ultrasound, obstetric, and cytogenetic databases for all second-trimester fetuses with measured NBLs. Fetuses with Down syndrome were identified and excluded from the analysis. Linear regression curves were generated for NBL by BPD according to race and ethnicity. Categories used were African American, Hispanic, Asian, and white. Analysis of variance was used to compare mean variation of observed from expected NBL by BPD according to race and ethnicity. RESULTS: There were 717 fetuses with NBL-by-BPD pairs who were available for analysis in our population, including 139 African American, 58 Hispanic, 22 Asian, and 498 white fetuses. Nasal bone length was highly correlated with BPD for each race (P < .001). Mean variances of observed from expected NBL by BPD were statistically different according to race or ethnicity (P = .0092). CONCLUSIONS: Race and ethnicity significantly affect the mean regression line of expected NBL by BPD among fetuses in the second trimester. Genetic sonographic norms, therefore, appear to require race- and ethnicity-specific formulas for NBL.

Down syndrome screening using race-specific femur length.

OBJECTIVE: The study was undertaken to evaluate the influence of maternal race on fetal femur length when screening for Down syndrome. STUDY DESIGN: We reviewed our patient databases to obtain fetal biometry from 15 to 22 weeks' gestation, maternal race, and cases of Down syndrome. Institution and race-specific regression lines for femur length (FL) to biparietal diameter (BPD) were created. The efficiency of using published expected FL was compared with our institution and race-specific regression in screening for Down syndrome. RESULTS: There were 4350 African American, 4271 white, 2315 Hispanic, and 654 Asian subjects and 42 cases of Down syndrome (1:276) included in the study. Our institutionally derived regression for FL by BPD had an R(2) of 0.82. Regression lines for FL by BPD generated by race had an R(2) of 0.86, 0.84, 0.83, and 0.80 for African American, Hispanic, Asian, and white subjects, respectively. The race-specific regression was no better than institution-specific data. CONCLUSION: Using institution-specific FL was more efficient in screening for Down syndrome than published expected FL; race-specific analysis did not improve efficiency.

Variation of fetal humeral length in second-trimester fetuses according to race and ethnicity.

OBJECTIVE: To determine the influence of race and ethnicity on the expected humeral length based on biparietal diameter measured in second-trimester fetuses. METHODS: We searched our ultrasound, obstetric, and cytogenetic databases from 1995 through 2001 for all fetuses who underwent an anatomic survey between 15 and 22 weeks' gestation. Fetuses with Down syndrome were identified and removed for separate analysis. Linear regression curves were generated for humeral length by biparietal diameter according to race and ethnicity. Analysis of variance was used to compare the mean variation of observed from expected humeral length by biparietal diameter according to race and ethnicity. RESULTS: There were 11,278 humeral length-by-biparietal diameter pairs that were available for analysis in our population, including 4202 African American, 2269 Hispanic, 639 Asian, and 4168 white fetuses. Humeral length was highly correlated with biparietal diameter for each race (R2 = 0.8). There were no differences in mean variances according to race or ethnicity (P = .75). CONCLUSIONS: Race and ethnicity do not affect the mean regression line of expected humeral length by biparietal diameter among fetuses in the second trimester. Genetic sonographic norms, therefore, do not require race- or ethnic-specific formulas for humeral length.

Clinical implications of velamentous cord insertion in triplet gestations.

OBJECTIVE: The purpose of this study was to determine the incidence of velamentous cord insertion and to evaluate the association between velamentous cord insertion and small-for-gestational age infants in triplet gestations. STUDY DESIGN: We reviewed our computerized database to identify all cases of velamentous cord insertion in triplet gestations who were delivered at our institution from January 1995 through December 1999. Triplet gestations without velamentous cord insertion who were delivered during this period were used as control subjects. Birth weights and pregnancy outcomes were obtained from medical records. Data were analyzed with descriptive statistics, analysis of variance, and chi(2) with Fisher exact test, where appropriate. RESULTS: Thirty-nine sets of triplets (117 infants) were delivered during the study period. Of these, 11 sets of triplets (28.2%) had a velamentous insertion of at least one umbilical cord. Infants with velamentous cord insertion were more likely to be small-for-gestational age than infants without velamentous cord insertion (33% vs 8%, P =.02). There were no significant differences in the rates of pregnancy complications between the two groups. CONCLUSION: Velamentous cord insertion is found frequently in triplet gestations and is significantly associated with small-for-gestational age in triplet neonates.

Down syndrome births in the United States from 1989 to 2001.

OBJECTIVE: We investigated the observed and expected Down syndrome livebirths in the US from 1989 to 2001. STUDY DESIGN: Using birth certificate data, we recorded maternal age-specific live births from 1989 to 2001, and stratified them by women 15 to 34 and 35 to 49 years old. We estimated Down syndrome live births from 1989 to 2001, assuming no terminations. We recorded Down syndrome live births by year from 1989 to 2001. RESULTS: Despite an expected 1.32-fold increase in Down syndrome live birth rates from 1989 to 2001, Down syndrome live births actually declined. In 1989, the rate of Down syndrome cases was 15% lower than expected, decreasing to 51% by 1998. Women 15 to 34 had 45% fewer affected pregnancies in 2001, while women 35 to 49 had 53% fewer in 2001. We estimated that Down syndrome live births decreased from 3962 in 1989 to 3654 in 2001. CONCLUSION: Down syndrome live births declined in the US despite an expected increase caused by delayed or extended childbearing.

Use of the mitral valve-tricuspid valve distance as a marker of fetal endocardial cushion defects.

OBJECTIVE: The purpose of this study was to compare the mitral valve-tricuspid valve distance in second-trimester fetuses with normal cardiac anatomy versus those fetuses with endocardial cushion defects. STUDY DESIGN: We identified fetuses between 16 and 24 weeks of gestation. The distance between the insertions of the medial leaflets of the mitral and tricuspid valves were obtained. Linear regression curves were generated. RESULTS: The mean mitral valve-tricuspid valve distance for 86 fetuses with normal cardiac anatomy was 2.02 mm, compared with 0.37 mm in 13 fetuses with endocardial cushion defects ( P = .0001). Linear regression curve correlating mitral valve-tricuspid valve distance with gestational age showed a gradual slope (R 2 = 0.28; P < .0001). With a mitral valve-tricuspid valve distance < 5th percentile as a marker for the diagnosis of endocardial cushion defect gave a sensitivity of 69.2%, a specificity of 100%, a positive predictive value of 100%, a negative predictive value of 95.6%, and a false-positive rate of 0% ( P = .0001). CONCLUSION: The mitral valve-tricuspid valve distance is useful clinically in the detection of endocardial cushion defects in second-trimester fetuses.

A randomized comparison of two regimens of misoprostol for second-trimester pregnancy termination.

OBJECTIVE: The purpose of this study was to compare the efficacy and side effects of two different misoprostol regimens for second-trimester pregnancy termination. STUDY DESIGN: We performed a randomized clinical trial in patients who were at 14 to 23 weeks of gestation and who were admitted for medical termination of pregnancy. All patients received 800 microg of vaginal misoprostol and were assigned randomly to 400 microg of oral misoprostol or 400 microg of vaginal misoprostol every 8 hours. Efficacy and side effects were compared. The mean induction time of the study group was compared with that of an historic control group that had received 400 microg vaginally every 12 hours. RESULTS: Forty-three women were assigned randomly, 22 women to vaginal misoprostol and 21 women to oral misoprostol. Induction time and hospital stay were slightly shorter for the oral group; however, the differences were not significant. Side effects were similar for both groups. CONCLUSION: After an initial 800 microg dose of vaginal misoprostol, a regimen of 400 microg of oral misoprostol every 8 hours is as effective as the same dose of vaginal misoprostol with no additional side effects, which provides a convenient alternative for midtrimester pregnancy termination.

Antenatal Down syndrome screening in the United States in 2001: a survey of maternal-fetal medicine specialists.

OBJECTIVE: Our objectives were to determine patterns of antenatal Down syndrome screening and risk adjustment by maternal-fetal medicine specialists in the United States in 2001. STUDY DESIGN: A survey to investigate Down syndrome screening practice patterns was mailed to the 1,638 members of the Society of Maternal-Fetal Medicine in the United States. Practice demographics, screening patterns, and the numeric risks quoted in counseling were analyzed. RESULTS: Five hundred forty-three specialists (33.2%) responded; 530 of these specialists (97.6%) performed antenatal Down syndrome screening; all of them offered second-trimester screening, and 247 of them (45.5%) offered first-trimester screening. With the use of second-trimester ultrasonography, risk was increased by 69.4% of respondents and decreased by 33.1%. Amniocentesis was the most frequently used diagnostic test (83.2%), with loss rates quoted at 1:100 to 1:1,000. CONCLUSION: Maternal-fetal medicine specialists show a wide in variation practices used for Down syndrome screening, modification of risk, and quoted procedure-related loss rates. This information calls for a consensus regarding risks that are quoted in Down syndrome counseling.