Biomedical subjects

Harish M Sehdev

Publications and source records attributed to Harish M Sehdev.

9 recordsLinked to original sources

PubMed2006

Evaluating the thresholds of abnormal second trimester multiple marker screening tests associated with intra-uterine growth restriction.

Our objective was to evaluate the optimal thresholds for unexplained abnormal multiple marker screening (MMS) results that are associated with intrauterine growth restriction (IUGR). This was a case-control study from our perinatal database. MMS analyte levels (multiples of median [MoM]) of cases with IUGR (birthweight < 5th percentile for gestational age) were compared with a control group without IUGR. Pregnancies with fetal anomalies were excluded. Biochemical markers evaluated include alpha-fetoprotein (AFP), human chorionic gonadotropin (hCG), and unconjugated estriol (uE3). Using receiver operating characteristic curves, the optimal thresholds of MMS (OTMs) associated with IUGR were determined. We identified 255 (12.3%) cases with IUGR and complete MMS records from the database. These were compared with 1785 controls without IUGR randomly selected from our perinatal database in a 1:7 ratio. The OTMs associated with IUGR were AFP > 2.0 MoM (odds ratio [OR] = 2.3; 95% confidence interval [CI], 1.4 to 3.7), hCG > 2.5 MoM (OR = 1.8; 95% CI, 1.1 to 3.2) and uE3 < 0.9 MoM (OR = 2.7; 95% CI, 2.0 to 3.7). The sensitivity, specificity, and positive and negative predictive values for predicting IUGR in the presence of at least one abnormal MMS were 46, 66, 11, and 90%, respectively. Elevated AFP > 2.0 MoM and hCG > 2.5 MoM were the most specific markers for MMS, with specificity of 94 and 95%, respectively. When all three analytes were abnormal, the specificity for predicting IUGR increased to 99%. Abnormal MMS results are associated with IUGR. As a screening tool for IUGR, the biochemical markers were associated with poor sensitivity. Elevated AFP and hCG, however, were highly specific in predicting IUGR. The provided thresholds could be useful in designing policies regarding women who would benefit most from sonographic screening for IUGR.

Adult↗

PubMed2006

Advanced maternal age is an independent risk factor for intrauterine growth restriction.

Reports on the association between advanced maternal age (AMA) and intrauterine growth restriction (IUGR) are conflicting. Our objective was to determine if AMA is an independent risk factor for IUGR. Our case-control study compared cases with IUGR (birthweight<10th percentile for gestational age) and a control group without IUGR. Gestational ages were all confirmed by ultrasound. The study included only singletons and fetal anomalies were excluded. Both groups were evaluated for maternal demographics and clinical risk factors. AMA was defined as maternal age>35 years. Univariate and multivariate analyses were used to examine associations. During the study period, there were 824 cases with IUGR meeting the inclusion criteria; these were compared with 1648 controls (no IUGR) randomly selected from the same population during the same study period. The significant factors associated with IUGR multivariate analyses were black race (odds ratio [OR], 22.4; 95% confidence interval [CI], 17.8 to 28); chronic hypertension (OR, 2.2; 95% CI, 1.5 to 3.2); pregestational diabetes (OR, 3.3; 95% CI, 1.6 to 7) illicit drug use (OR, 3.3; 95% CI, 2.2 to 5.2), and AMA (OR, 1.4; 95% CI, 1.1 to 1.8). There was a positive dose-response association between increasing maternal age and increasing risk for IUGR. At maternal age of 40 years or older, the OR and 95% CI for IUGR was 3.2 and 1.9 to 5.4, respectively. AMA is an independent risk factor for IUGR. Our findings suggest that screening for IUGR is indicated in women age 35 years or older.

Adolescent↗

PubMed2006

Evaluating the efficiency of using second-trimester nasal bone hypoplasia as a single or a combined marker for fetal aneuploidy.

OBJECTIVE: Although second-trimester nasal bone (NB) hypoplasia has been associated with fetal aneuploidy, its role as a single marker is still uncertain. Our objective was to evaluate the efficiency of NB hypoplasia as an independent marker for fetal aneuploidy. METHODS: This was a prospective cohort study of women undergoing an anatomic survey between 16 and 22 weeks' gestation. The fetal NB and other markers of fetal aneuploidy, including nuchal fold, femur and humeral lengths, choroid plexus cysts, major fetal anomalies, echogenic bowel, pyelectasis, and hypoplastic fifth digits, were evaluated. Nasal bone hypoplasia was defined either as an absent NB or by a ratio of the biparietal diameter to NB. Fetuses or infants with fetal aneuploidy were compared with those without for the presence of NB hypoplasia either as a single marker or in the presence of other markers for aneuploidy. RESULTS: Of 2885 women evaluated, NB measurements were obtained in 2465 (85%). There were 35 (1.4%) cases with fetal aneuploidy. The sensitivity and specificity of a single NB in detecting Down syndrome varied from 23% to 64% and 57% to 99%, respectively, depending on the definition of NB hypoplasia used. There was an improvement in the efficiency of using the NB when combined with other markers, with sensitivity and specificity increasing from 59% to 82% and 74% to 87%, respectively. CONCLUSIONS: Nasal bone hypoplasia is a marker for fetal aneuploidy. The combination of the NB with other makers was associated with an improvement in detection of fetal aneuploidy.

Abnormalities, Multiple↗

PubMed2005

A cost-effectiveness analysis of prenatal screening strategies for Down syndrome.

OBJECTIVE: To evaluate which Down syndrome screening strategy is the most cost-effective. METHODS: Using decision-analysis modeling, we compared the cost-effectiveness of 9 screening strategies for Down syndrome: 1) no screening, 2) first-trimester nuchal translucency (NT) only, 3) first-trimester combined NT and serum screen, 4) first-trimester serum only, 5) quadruple screen, 6) integrated screening, 7) sequential screening, 8) integrated serum only, or 9) maternal age. Costs included cost of tests and resources used for raising a child with Down syndrome. One-way and multiway sensitivity analyses were performed for all model variables. The main outcome measures were cost per Down syndrome case detected, rate of delivering a liveborn neonate with Down syndrome, and rate of diagnostic procedure-related pregnancy loss for each strategy. RESULTS: Sequential screening detected more Down syndrome cases compared with the other strategies, but it had a higher procedure-related loss rate. Integrated serum screening was the most cost-effective strategy. Sensitivity analyses revealed the model to be robust over a wide range of values for the variables. The addition of the cost of genetic sonogram to the second-trimester strategies resulted in first-trimester combined screening becoming the most cost-effective strategy. CONCLUSION: Within our baseline assumptions, integrated serum screening was the most cost-effective screening strategy for Down syndrome. If the cost of nuchal translucency is less than dollars 57 or when genetic sonogram is included in the second-trimester strategies, first-trimester combined screening became the most cost-effective strategy. LEVEL OF EVIDENCE: III.

Adult↗

PubMed2004

The effects of the time interval from antenatal corticosteroid exposure to delivery on neonatal outcome of very low birth weight infants.

OBJECTIVE: The purpose of this study was to determine whether the interval between antenatal steroid exposure and delivery influences neonatal outcome in very low birth weight infants. STUDY DESIGN: A retrospective review was performed of all live-born singleton infants who weighed between 500 and 1500 g and who were exposed to a partial course (1 dose) or a complete course (2 12-mg doses of betamethasone given 24 hours apart) of antenatal corticosteroids. Infants were divided into 4 groups, depending on the interval between the first dose of antenatal corticosteroids and delivery (<24 hours, between 24 and 48 hours, between 48 hours and 7 days, and >7 days). Logistic regression was used to control for differences between the 4 groups. RESULTS: Three hundred twenty-five singleton deliveries were reviewed. Gestational age at delivery and birth weight were similar for all 4 groups. The babies in the last group were treated with antenatal corticosteroids at a slightly earlier gestational age. There was no statistical difference between the groups with respect to respiratory distress syndrome treated with surfactant, intraventricular hemorrhage, necrotizing enterocolitis, and deaths. CONCLUSION: In infants who weighed 500 to 1500 g, the time interval between exposure to antenatal corticosteroids and delivery does not appear to affect neonatal outcome. Further studies should evaluate the effects of antenatal corticosteroids and the effects of the interval from exposure to delivery in very low birth weight infants.

Adult↗

PubMed2004

False-positive 1-hour glucose challenge test and adverse perinatal outcomes.

OBJECTIVE: To determine whether a false-positive 1-hour glucose challenge test (GCT) is associated with perinatal complications. METHODS: We performed a retrospective cohort study of 1825 eligible pregnant women among a cohort of 1998 patients. Patients were screened for gestational diabetes mellitus (GDM) with the 1-hour 50-g GCT at 24-28 gestational weeks. A false-positive GCT was defined as a result greater than or equal to 135 mg/dL followed by a normal 3-hour glucose tolerance test (GTT). We compared the negative GCT and false-positive GCT cohorts for a composite perinatal outcome variable that included fetal macrosomia, antenatal death, shoulder dystocia, chorioamnionitis, preeclampsia, intensive care nursery admission, and postpartum endometritis. Secondary outcomes included cesarean delivery and each component variable of the composite. Unadjusted, stratified, and multiple logistic regression analyses were used to investigate the association between a false-positive GCT and the development of perinatal complications. RESULTS: We identified 164 patients with a false-positive GCT and 50 patients with GDM. The false-positive GCT cohort on average was older, of higher parity, had a higher body mass index, and more frequently had chronic hypertension, sickle cell trait, and elevated midtrimester human chorionic gonadotropin levels. The false-positive GCT cohort more frequently had adverse perinatal outcomes, including the composite perinatal outcome (odds ratio [OR] 5.96, 95% confidence interval[CI]1.47,24.16), macrosomia greater than 4500 g (OR 3.66, 95% CI 1.30, 10.32), antenatal death (OR 4.61, 95% CI 0.77, 27.48), shoulder dystocia (OR 2.85, 95% CI 1.25, 6.51), endometritis (OR 2.18, 95% CI 1.03, 4.63), and cesarean delivery (OR 1.76, 95% CI 0.99, 3.14). CONCLUSION: A false-positive GCT is an independent risk factor for adverse perinatal outcomes.

Adult↗

PubMed2004

The association between fetal nasal bone hypoplasia and aneuploidy.

OBJECTIVE: To determine the association between fetal nasal bone hypoplasia and aneuploidy in women undergoing prenatal diagnosis. METHODS: A prospective cohort study involving women undergoing chorionic villus sampling and amniocentesis for an increased risk of aneuploidy. Fetal biometric and nasal bone measurements were obtained at the time of prenatal diagnosis and compared with karyotypes. Nasal bone hypoplasia was defined as nasal bone less than 2.5th percentile for the gestational age. RESULTS: A total of 632 fetuses were evaluated. Twenty-nine (4.6%) had an aneuploidy (18 trisomy 21, 5 trisomy 18, 1 Turner's syndrome, one Marker chromosome 1, 2 sex chromosome anomalies, and 2 triploidy). Nasal bone measurements were documented in 29 aneuploid fetuses. The nasal bone was either absent or hypoplastic in 12 of 29 (41%) fetuses with aneuploidy and in 8 of 18 (44%) with trisomy 21. By using receiver operating characteristics curves, the optimal threshold of nasal bone hypoplasia associated with fetal aneuploidy was a biparietal diameter/nasal bone ratio of 11 or greater. The sensitivity, specificity, and positive and negative predictive values for the detection of fetal aneuploidy were 50%, 93%, 24%, and 98%, respectively. CONCLUSION: Absent or hypoplastic nasal bone is a marker for fetal aneuploidy in a high-risk population. However, this marker needs to be evaluated by larger prospective studies in low-risk populations before adoption for clinical use.

Adult↗

PubMed2003

Pregnant women with the sickle cell trait are not at increased risk for developing preeclampsia.

The primary objective of this study was to determine whether having the sickle cell trait is independently associated with preeclampsia. We performed a retrospective cohort study of 1998 pregnant patients who either did or did not have the sickle cell trait. All patients were screened for the sickle trait using the "Sickledex" test. Data on neonatal and maternal outcome, including preeclampsia, and potential confounding variables were abstracted from medical records. Unadjusted, stratified, and multiple logistic regression analyses were used to identify interactions, and confounding between multiple variables and the association between sickle cell trait and preeclampsia. With an anticipated 6.5% rate of preeclampsia, and alpha = 0.05, this cohort study has 80% power to detect a relative risk (RR) of 2.3 for preeclampsia. Univariate analysis revealed that the two cohorts were similar with regard to primiparity, maternal age, chronic diseases, birth weight, and gestational age at delivery, but the sickle cell trait cohort was more likely to have gestational diabetes and had a higher mean body mass index (BMI). In the univariate analysis, the sickle cell trait cohort was not at increased risk for preeclampsia [unadjusted RR = 0.5, 95% CI (0.2-1.6)]. After controlling for potential confounding variables with logistic regression analysis, sickle trait was not independently associated with preeclampsia [adjusted RR = 0.5, 95% CI (0.2- 1.6)]. In contrast to prior work, these data suggest that the sickle cell trait is not an independent risk factor for preeclampsia or postpartum complications. In fact, the data are more consistent with the sickle trait being protective for developing preeclampsia.

Adult↗

PubMed2003

Neonatal outcome after exposure to indomethacin in utero: a retrospective case cohort study.

OBJECTIVE: This study was undertaken to determine the clinical outcome for neonates who were exposed to indomethacin during gestation. STUDY DESIGN: We identified 124 infants with in utero exposure to indomethacin and matched them to 124 infants whose mothers did not receive indomethacin. The two groups were matched for gestational age at birth, sex, and exposure to antenatal betamethasone. Sixty-two of the indomethacin-exposed infants were born within 48 hours of last exposure. These infants were also compared with their matched controls. RESULTS: There were no significant differences between the indomethacin-exposed infants and control infants in birth weight, Apgar scores, frequency of cesarean section deliveries, and multiple gestation. The incidence of respiratory distress syndrome, need for surfactant treatment, patent ductus arteriosus, necrotizing enterocolitis, and intraventricular hemorrhage was similar between the indomethacin-exposed group and the control group. Indomethacin-exposed infants who were born within 48 hours of last exposure had similar incidence of respiratory distress syndrome but greater need for surfactant treatment (P=.02) compared with controls. All other complication rates were similar. CONCLUSION: Indomethacin exposure in our study was not associated with increased neonatal complications for infants delivered within or beyond 48 hours of last exposure.

Apgar Score↗