Biomedical subjects

Brian L Shaffer

Publications and source records attributed to Brian L Shaffer.

6 recordsLinked to original sources

PubMed2006

Face presentation: predictors and delivery route.

OBJECTIVE: We sought to identify associated characteristics of face presentation and to examine factors that were associated with mode of delivery in the setting of face presentation. STUDY DESIGN: This was a retrospective cohort study of women who were diagnosed with face presentation during labor. We examined maternal, fetal, and labor characteristics to determine the associations and predictors of cesarean delivery. RESULTS: Fetuses in face presentation were more likely preterm, < 2500 g, and black. An Apgar score of < 7 at 5 minutes was more common in face presentation (10.9%) compared with vertex presentation (4.4%; P = .018). Rates of umbilical artery base excess < -12 or pH < 7.0 were not different. Cesarean delivery was less common in women who received oxytocin (adjusted odds ratio, 0.18; 95% CI, 0.03-0.95) and in women with mentum anterior (14%) as compared with mentum posterior presentation (85%; P < .001). CONCLUSION: This study confirms the association between face presentation and prematurity. The association with black ethnicity may be related to differences in pelvic anatomy. Although face presentation was associated with decreased Apgar scores, no other indicators of fetal asphyxia were identified. Cesarean delivery rates were higher in women with mentum posterior face presentation and in women who did not receive oxytocin.

Apgar Score↗

PubMed2006

Variation in the decision to terminate pregnancy in the setting of fetal aneuploidy.

OBJECTIVE: To investigate the rate of pregnancy termination for various fetal aneuploidies, and to evaluate predictors of this choice. METHODS: A retrospective cohort study identified all patients with any of seven common fetal aneuploidies (trisomies 21, 18, and 13; 45,X, 47,XXX, 47,XXY, and 47,XYY) at a referral prenatal diagnosis unit from 1983 to 2003. We abstracted type of aneuploidy, time and type of diagnostic procedure, maternal age, and ethnicity as predictors of the decision to terminate. Statistical comparisons were made using the chi-square test. Potential confounding variables were controlled for using multivariate logistic regression. RESULTS: Overall, there were 833 patients who had fetuses with aneuploidy. In our study population, the overall rate of termination was 81%: 86% in cases of autosomal trisomy and 60% in cases of sex chromosome aneuploidy (SCA) (p < 0.001). Rates were lowest in cases with the least severe prognosis, 47,XYY (57%) and 47,XXX (40%) compared with 45,X (65%) and 47,XXY (70%) (p = 0.05). Patients with SCA detected by chorionic villus sampling (CVS) had a higher termination rate than those who had undergone amniocentesis (77% vs 55%, p = 0.015). Increased maternal age was associated with higher termination rates in autosomal trisomy (88% vs 76% p < 0.001) and a trend toward decreased rates in those with SCA (55% vs 71%, p = 0.06). Hispanic women were less likely to terminate pregnancy (69%, p = 0.01) than those from other racial/ethnic groups. CONCLUSION: Type and severity of aneuploidy, type of diagnostic procedure, maternal age, and ethnicity contribute to patients' decision-making in the setting of fetal aneuploidy.

Abortion, Eugenic↗

PubMed2006

Manual rotation of the fetal occiput: predictors of success and delivery.

OBJECTIVE: The purpose of the study was to define predictors of successful rotation and rate of cesarean delivery after manual rotation of the fetal occiput from occiput posterior or transverse position. STUDY DESIGN: A retrospective cohort study comprised patients who underwent a trial of manual rotation of the fetal occiput from occiput posterior or occiput transverse position. Successful rotation was defined as delivery in the occiput anterior position. We examined maternal, fetal, and labor characteristics as predictors of both fetal position at delivery and cesarean delivery. RESULTS: Multiparity (odds ratio, 2.5; 95% CI, 1.5-3.8) and maternal age < 35 years (odds ratio, 2.0; 95% CI, 1.1-3.4) were associated with successful manual rotation of the fetal occiput. After successful rotation, the cesarean delivery rate was 2%, compared with 34% if the rotation failed (P < .001). Asian ethnicity, nulliparity, age > 35 years, labor induction, and epidural usage were associated with higher rates of cesarean delivery. CONCLUSION: After successful manual rotation of the fetal occiput, women had lower cesarean delivery rates than women with unsuccessful rotations. Multiparity and maternal age of < 35 years were associated with more successful rotations.

Adult↗

PubMed2006

Associated factors and outcomes of persistent occiput posterior position: A retrospective cohort study from 1976 to 2001.

OBJECTIVE: To identify maternal and fetal risk factors associated with persistent occiput posterior position at delivery, and to examine the association of occiput posterior position with subsequent obstetric outcomes. METHODS: This is a retrospective cohort study of 30 839 term, cephalic, singleton births. Women with persistent occiput posterior (OP) position at delivery were compared to those with occiput anterior (OA) position. Demographics, obstetric history, and labor management were evaluated and subsequent obstetric outcomes examined. Potential confounding variables were controlled for using multivariate logistic regression analysis. RESULTS: The overall frequency of OP position was 8.3% in the study population. When compared to Caucasians, a higher rate of OP was observed among African-Americans (OR = 1.4, 95% CI 1.25-1.64) while no other racial/ethnic differences were noted. Other associated factors included nulliparity, maternal age > or =35, gestational age > or =41 weeks, and birth weight >4000 g, as well as artificial rupture of the membranes (AROM) and epidural anesthesia (p < 0.001 for all). Persistent OP was associated with increased rates of operative vaginal (OR = 4.14, 95% CI 3.57-4.81) and cesarean deliveries (OR = 13.45, 95% CI 11.94-15.15) and other peripartum complications including third or fourth degree perineal lacerations (OR = 2.38, 95% CI 2.03-2.79), and chorioamnionitis (OR = 2.10, 95% CI 1.81-2.44). CONCLUSION: Epidural use, AROM, African-American ethnicity, nulliparity, and birth weight >4000 g are associated with persistent OP position at delivery, with higher rates of operative deliveries and obstetric complications. This information can be useful in counseling patients regarding risks and associated outcomes of persistent OP position.

Adult↗

PubMed2006

The association between persistent occiput posterior position and neonatal outcomes.

OBJECTIVE: To examine the effect of persistent occiput posterior position on neonatal outcome. METHODS: This is a retrospective cohort study of 31,392 term, cephalic, singleton births. Women with neonates born in persistent occiput posterior position at delivery were compared to those with occiput anterior position. Women with occiput transverse position were excluded. The association between occiput posterior position and neonatal outcomes, including 5-minute Apgar scores, umbilical cord gases, meconium-stained amniotic fluid, meconium aspiration syndrome, birth trauma, admission to the intensive care nursery, and length of stay were examined using chi(2) and Student t tests. Potential confounders (maternal age, ethnicity, parity, gestational age, epidural anesthesia, labor induction, length of labor, meconium, chorioamnionitis, birth weight, and year of delivery) were controlled for by using multivariable logistic regression and linear regression analyses. RESULTS: There were 2,591 (8.2%) neonates delivered in occiput posterior position of the total cohort of 31,392 deliveries. Compared with occiput anterior, neonates delivered in occiput posterior position had higher risks for adverse outcomes, including 5-minute Apgar score less than 7 (odds ratio [OR] 1.50, 95% confidence interval [CI] 1.17-1.91), acidemic umbilical cord gases (OR 2.05, 95% CI 1.52-2.77), meconium-stained amniotic fluid (OR 1.29, 95% CI 1.17-1.42), birth trauma (OR 1.77, 95% CI 1.22-2.57), admission to the intensive care nursery (OR 1.57, 95% CI 1.28-1.92), and longer neonatal stay in the hospital (OR 2.69, 95% CI 2.22-3.25). CONCLUSION: Persistent occiput posterior position at delivery is associated with higher risks of adverse neonatal outcomes compared with neonates delivered in the occiput anterior position. This information may be important in counseling women who experience persistent occiput posterior position in labor. LEVEL OF EVIDENCE: II-2.

Adult↗

PubMed2006

History of miscarriage and increased incidence of fetal aneuploidy in subsequent pregnancy.

OBJECTIVE: The purpose of this study was to examine the association between history of spontaneous abortion and aneuploidy in a subsequent pregnancy. METHODS: This was a retrospective cohort study of women who underwent fetal karyotype analysis with amniocentesis or chorionic villus sampling at a single prenatal diagnosis center. Information on spontaneous abortions, parity, maternal age, ethnicity, type of prenatal diagnosis, and karyotype was assessed. Univariable and multivariable analyses were conducted. RESULTS: A total of 46,939 women were included in our analysis. Women with no prior spontaneous abortions had a 1.39% risk for any aneuploidy. In women with one prior spontaneous abortion, this risk increased to 1.67%; for women with 2 previous spontaneous abortions, the risk increased to 1.84%; and for those women who had had 3 or more prior spontaneous abortions, the risk increased further to 2.18% (P < .007). When controlling for maternal age, parity, ethnicity, and mode of prenatal diagnosis and compared with women with no prior spontaneous abortions, women with one prior spontaneous abortion (adjusted odds ratio [AOR] 1.21, 95% confidence interval [CI] 1.01-1.47) or 3 or more prior spontaneous abortions (AOR 1.51, 95% CI 1.02-2.25) had a statistically significant increase in aneuploidy in a subsequent pregnancy. Women with 2 prior spontaneous abortions had an AOR of 1.26 for aneuploidy, but the 95% CI contained unity. CONCLUSION: An increased risk of karyotypic abnormality identified at the time of prenatal diagnosis is demonstrated in patients with an increasing number of spontaneous abortions. This study provides information regarding this risk among women presenting for prenatal diagnosis. According to our data, for a woman with an a priori risk of 1 in 300 for Down syndrome, 3 prior spontaneous abortions would increase that risk by 47% to 1 in 204. These results should be confirmed in low-risk populations.

Abortion, Spontaneous↗