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Yinka Oyelese

Publications and source records attributed to Yinka Oyelese.

At least 19 recordsLinked to original sources

Evidence of placental abruption as a chronic process: associations with vaginal bleeding early in pregnancy and placental lesions.

BACKGROUND: Clinicians widely regard placental abruption as an acute event, though accumulating data point towards abruption being the end-result of chronic processes early in pregnancy, and perhaps even extending to conception. The Collaborative Perinatal Project was a prospective cohort study performed from 1959 to 1966 in the United States. Since enrolled pregnancies were managed without the biases created by modern perinatal surveillance and interventions, the natural history of disease in these data is ideal to study obstetrical complications such as placental abruption. OBJECTIVE: We assessed the associations versus contributions of the clinical feature of early gestational vaginal bleeding and histologic lesions (chronic and acute) with placental abruption. STUDY DESIGN: Women enrolled in the Collaborative Perinatal Project (1959-1966) were used, restricting the analysis to those that delivered singleton births (n=46,364). Risks of placental abruption were compared between women with and without vaginal bleeding at <20 weeks gestation. We also examined the relationships between placental abruption and chronic and acute histologic lesions, including infarcts, decidual necrosis, presence of macrophages in the decidua, amnion or chorion, and neutrophil infiltration in the amnion, chorion, placental surface, and umbilical vein. RESULTS: Any episode of vaginal bleeding at <20 weeks in pregnancy conferred an increased risk of placental abruption (adjusted relative risk (RR) 1.6, 95% confidence interval (CI) 1.3, 1.8). The greatest risk occurred with bleeding in both the first two trimesters (RR 3.1, 95% CI 2.3, 4.1). The presence of histologic lesions in the placenta, cord and membranes similarly carried an increased risk of placental abruption, even in the absence of vaginal bleeding. The risk of abruption was, however, highest in the presence of both histologic lesions and vaginal bleeding early in pregnancy. CONCLUSION: Vaginal bleeding early in pregnancy and histologic lesions of the placenta, umbilical cord, and membranes are associated with increased risk of placental abruption in later pregnancy. However, the increased risk associated with placental lesions, especially chronic inflammatory lesions, even in the absence of early vaginal bleeding, suggests that prolonged inflammation may be implicated in placental abruption.

Abruptio Placentae↗

Is race a determinant of stillbirth recurrence?

BACKGROUND: A history of stillbirth may result in an increased risk for recurrence, although information regarding this remains scanty. It is also uncertain whether race is a determinant of stillbirth recurrence given that the risk of stillbirth varies across racial and ethnic populations. METHODS: The Missouri maternally linked cohort data set containing births from 1978 through 1997 was used. We identified the study group (women who experienced a stillbirth in the first pregnancy) and a comparison group (women who delivered a live birth in their first pregnancy) and compared the outcome (stillbirth) in the second pregnancy between the 2 groups. RESULTS: We analyzed 404,180 women with information on first and second pregnancies (1,979 [0.5%] in the study arm, and 402,201 [99.5%] in the comparison arm). Of the 1,929 cases of stillbirths in the second pregnancy, 45 cases occurred in mothers with a history of stillbirth (stillbirth rate = 22.7/1000) and 1,884 in the comparison group (stillbirth rate 4.7/1,000, P < .001). The adjusted risk of stillbirth was almost 5-fold as high in women with a prior stillbirth (odds ratio 4.7, 95% confidence interval 3.3-6.6). Analysis across racial groups revealed that whites had lower absolute risk for stillbirth recurrence than African Americans (19.1/1,000 compared with 35.9/1,000, P < .05). The elevated stillbirth recurrence risk was confirmed after adjusting for potential confounders (odds ratio 2.6, 95% confidence interval 1.2-5.7). CONCLUSION: History of stillbirth is associated with a 5-fold increase for subsequent stillbirth. The recurrence of stillbirth is almost tripled in African Americans as compared with whites. LEVEL OF EVIDENCE: II-2.

Adult↗

Previous cesarean delivery and risks of placenta previa and placental abruption.

OBJECTIVE: To examine the association between cesarean delivery and previa and abruption in subsequent pregnancies. METHODS: A retrospective cohort study of first 2 (n = 156,475) and first 3 (n = 31,102) consecutive singleton pregnancies using the 1989-1997 Missouri longitudinally linked data were performed. Relative risk (RR) was used to quantify the associations between cesarean delivery and risks of previa and abruption in subsequent pregnancies, after adjusting for several confounders. RESULTS: Rates of previa and abruption were 4.4 (n = 694) and 7.9 (n = 1,243) per 1,000 births, respectively. The pregnancy after a cesarean delivery was associated with increased risk of previa (0.63%) compared with a vaginal delivery (0.38%, RR 1.5, 95% confidence interval [CI] 1.3-1.8). Cesarean delivery in the first and second births conferred a two-fold increased risk of previa in the third pregnancy (RR 2.0, 95% CI 1.3-3.0) compared with first two vaginal deliveries. Women with a cesarean first birth were more likely to have an abruption in the second pregnancy (0.95%) compared with women who had a vaginal first birth (0.74%, RR 1.3, 95% CI 1.2-1.5). Two consecutive cesarean deliveries were associated with a 30% increased risk of abruption in the third pregnancy (RR 1.3, 95% CI 1.0-1.8). A second pregnancy within a year after a cesarean delivery was associated with increased risks of previa (RR 1.7, 95% CI 0.9-3.1) and abruption (RR 1.5, 95% CI 1.1-2.3). CONCLUSION: A cesarean first birth is associated with increased risks of previa and abruption in the second pregnancy. There is a dose-response pattern in the risk of previa, with increasing number of prior cesarean deliveries. A short interpregnancy interval is associated with increased risks of previa and abruption. LEVEL OF EVIDENCE: II-2.

Abruptio Placentae↗

Placenta previa, placenta accreta, and vasa previa.

Placenta previa, placenta accreta, and vasa previa are important causes of bleeding in the second half of pregnancy and in labor. Risk factors for placenta previa include prior cesarean delivery, pregnancy termination, intrauterine surgery, smoking, multifetal gestation, increasing parity, and maternal age. The diagnostic modality of choice for placenta previa is transvaginal ultrasonography, and women with a complete placenta previa should be delivered by cesarean. Small studies suggest that, when the placenta to cervical os distance is greater than 2 cm, women may safely have a vaginal delivery. Regional anesthesia for cesarean delivery in women with placenta previa is safe. Delivery should take place at an institution with adequate blood banking facilities. The incidence of placenta accreta is rising, primarily because of the rise in cesarean delivery rates. This condition can be associated with massive blood loss at delivery. Prenatal diagnosis by imaging, followed by planning of peripartum management by a multidisciplinary team, may help reduce morbidity and mortality. Women known to have placenta accreta should be delivered by cesarean, and no attempt should be made to separate the placenta at the time of delivery. The majority of women with significant degrees of placenta accreta will require a hysterectomy. Although successful conservative management has been described, there are currently insufficient data to recommend this approach to management routinely. Vasa previa carries a risk of fetal exsanguination and death when the membranes rupture. The condition can be diagnosed prenatally by ultrasound examination. Good outcomes depend on prenatal diagnosis and cesarean delivery before the membranes rupture.

Balloon Occlusion↗

Meconium-stained amniotic fluid across gestation and neonatal acid-base status.

OBJECTIVE: To estimate whether the acid-base status of neonates born to women with meconium-stained amniotic fluid varies across gestation. METHODS: We carried out a retrospective cohort study of all pregnancies that were complicated by meconium-stained amniotic fluid in 2004. Cases were identified from a perinatal pathology database that contained data on all pregnancies complicated by meconium-stained amniotic fluid. Data abstracted from the charts included gestational age at delivery, umbilical arterial pH, birth weight, and the presence or absence of labor. Cases were stratified according to gestational age at delivery. The distribution of meconium-stained amniotic fluid across gestation was computed. The mean umbilical arterial pH values (with 95% confidence intervals) across gestation were assessed by analysis of variance. RESULTS: The mean umbilical arterial pH in women with meconium-stained amniotic fluid did not differ across gestation. The overall incidence of meconium-stained amniotic fluid was 12.0% (766 of 6,403 deliveries). The rates of meconium-stained amniotic fluid increased from 1.2% at 32 weeks to 100% at 42 weeks. CONCLUSION: The rising incidence of meconium-stained amniotic fluid with gestational age is consistent with the hypothesis that fetal maturation is a major etiologic factor in meconium passage. Also, the lack of variation of mean umbilical arterial pH across gestation suggests that fetal acidemia is not increased when meconium passage occurs earlier in pregnancy rather than at later gestational ages.

Adult↗

Placental abruption.

Placental abruption complicates about 1% of pregnancies and is a leading cause of vaginal bleeding in the latter half of pregnancy. It is also an important cause of perinatal mortality and morbidity. The maternal effect of abruption depends primarily on its severity, whereas its effect on the fetus is determined both by its severity and the gestational age at which it occurs. Risk factors for abruption include prior abruption, smoking, trauma, cocaine use, multifetal gestation, hypertension, preeclampsia, thrombophilias, advanced maternal age, preterm premature rupture of the membranes, intrauterine infections, and hydramnios. Abruption involving more than 50% of the placenta is frequently associated with fetal death. The diagnosis of abruption is a clinical one, and ultrasonography and the Kleihauer-Betke test are of limited value. The management of abruption should be individualized on a case-by-case basis depending on the severity of the abruption and the gestational age at which it occurs. In cases where fetal demise has occurred, vaginal delivery is preferable. Disseminated intravascular coagulopathy should be managed aggressively. When abruption occurs at or near term and maternal and fetal status are reassuring, conservative management with the goal of vaginal delivery may be reasonable. However, in the presence of fetal or maternal compromise, prompt delivery by cesarean is often indicated. Similarly, abruption at extremely preterm gestations may be managed conservatively in selected stable cases, with close monitoring and rapid delivery should deterioration occur. Most cases of placental abruption cannot be predicted or prevented. However, in some cases, maternal and infant outcomes can be optimized through attention to the risks and benefits of conservative management, ongoing evaluation of fetal and maternal well-being, and through expeditious delivery where appropriate.

Abruptio Placentae↗

Parity effect on preterm birth and growth outcomes among infants with isolated omphalocele.

OBJECTIVE: To assess the association between parity and fetal morbidity outcomes among omphalocele-affected fetuses. STUDY DESIGN: We carried out a retrospective study of 498 cases of isolated omphalocele (210 born to nulliparous and 288 to multiparous mothers) in New York State from 1983 through 1999. Infants of nulliparous mothers were compared to those of multiparous gravidas using adjusted odds ratios generated from a logistic regression. RESULTS: Omphalocele-affected fetuses of nulliparous mothers had a lower risk of being delivered preterm (odds ratio (OR)=0.49; 95% CI=0.27-0.90) but comparable risks for low birth weight (OR=1.01; 95% CI=0.60-1.72), very low birth weight (OR=0.33; 95% CI=0.09-1.20), very preterm birth (OR=0.42; 95% CI=0.15-1.16), and small size for gestational age (SGA) [OR=0.61; 95% CI=0.23-1.63]. CONCLUSION: Omphalocele-affected fetuses of multiparous mothers have double the risk for preterm birth compared to their nulliparous counterparts. This information is potentially useful in counseling parents whose fetuses have omphaloceles.

Adult↗

Placental abruption in the United States, 1979 through 2001: temporal trends and potential determinants.

OBJECTIVE: The purpose of this study was to evaluate temporal trends in abruption risk and to assess how much underlying changes in the clinical determinants may have affected these trends. STUDY DESIGN: We used the National Hospital Discharge Summary data (1979-2001), an annual survey of sampled non-federal, short stay, general, and specialty hospitals in the United States. Trends in abruption were assessed for the periods 1979 through 1981 and 1999 through 2001. Clinical determinants of abruption that were evaluated included hypertensive diseases, anemia, gestational diabetes mellitus, preterm labor, preterm premature rupture of membranes, chorioamnionitis, oligohydramnios, obstetric shock/trauma, uterine tumors, short umbilical cord, and velamentous cord insertion. Temporal trends in abruption were examined before and after adjustment for determinants through multivariable logistic regression. RESULTS: The rate of abruption increased 92% (95% CI, 88, 96) among black women between 1979-1981 (0.76%; n = 13,584 women) and 1999-2001 (1.43%; n = 18,960 women). Among white women, the rate increased by 15% (95% CI, 14,16) over the same period, from 0.82% (n = 66,186 women) in 1979-1981 to 0.94% (n = 59,284 women) in 1999-2001. The determinants that were associated with trends in abruption included anemia, gestational diabetes mellitus, preterm labor, short umbilical cord, and velamentous cord insertion, although their effects varied substantially by maternal race. CONCLUSION: The temporal increase in rates of abruption may reflect a true increase in risk or may be the result of improved diagnosis of both abruption and its determinants. Although the cause of abruption is still speculative, the trend is of concern and deserves scrutiny.

Abruptio Placentae↗

Delayed interval delivery in twin pregnancies in the United States: Impact on perinatal mortality and morbidity.

OBJECTIVE: To estimate the incidence of delayed interval delivery in twin pregnancies in the United States and evaluate the impact of delayed delivery on perinatal outcomes. STUDY DESIGN: A population-based retrospective cohort study was performed using the U.S. "matched multiple birth" file (1995 to 1998), restricting our analysis to twin sets in which the first twin was delivered vaginally at 22 to 28 weeks (n = 4257). Outcomes examined included perinatal and infant mortality and small-for-gestational-age births. Outcomes of second twins in pregnancies that underwent delayed interval delivery of 1, 2, 3, and >/=4 weeks were compared with those in which both twins were delivered contemporaneously. RESULTS: In this cohort, 6.1% (n = 258) of twins had delayed delivery (>/=1 week) of the second twin. Decreases in perinatal and infant mortality were observed only when the first twin was delivered at 22 to 23 weeks and when the delivery interval was </=3weeks. However, for intervals >/=4 weeks or when the first twin was delivered at 24 to 28 weeks (regardless of delivery interval), there was no benefit in perinatal or infant mortality. Delayed delivery of >/=4 weeks was associated with increased risk of small-for-gestational-age birth in the second twin, regardless of gestational age at delivery of the first. CONCLUSION: When a first twin was delivered at 22 to 23 weeks, delayed delivery of the second twin was associated with reduced perinatal and infant mortality of the second twin if the interval was less than 3 weeks. Delayed delivery of the second twin when the first was delivered at >/=24 weeks had no benefit on mortality.

Adult↗

Maternal anterior sacral meningocele in pregnancy.

Anterior sacral meningocele is a rare condition resulting from herniation of the meninges through a sacral defect. Women with this condition may undergo inappropriate surgery because the correct diagnosis is missed, resulting in serious complications. In labor, the cyst may rupture, with consequent meningitis and high maternal mortality. We report the case of a 31 year-old pregnant woman with an anterior sacral meningocele. We describe the role of magnetic resonance imaging in the evaluation and management planning in this condition. She was delivered by cesarean section at 34 weeks without complications. Accurate diagnosis and delivery by cesarean prior to labor are important in assuring good outcomes in women with anterior sacral meningoceles.

Adult↗

Trends in preterm birth and perinatal mortality among singletons: United States, 1989 through 2000.

OBJECTIVE: Despite the recent increase in preterm birth in the United States, trends in preterm birth subtypes have not been adequately examined. We examined trends in preterm birth among singletons following ruptured membranes, medical indications, and spontaneous preterm birth and evaluated the impact of these trends on perinatal mortality. METHODS: A population-based, retrospective cohort study comprising 46,375,578 women (16% blacks) who delivered singleton births in the United States, 1989 through 2000, was performed. Rates of preterm birth (< 37 weeks), their subtypes, and associated perinatal mortality (stillbirths at >/= 22 weeks plus neonatal deaths within 28 days), before and after adjustment for potential confounders, were derived from ecological logistic regression models. RESULTS: Preterm birth rates increased by 14% (95% confidence interval 13-15%) among whites from 8.3% to 9.4% and decreased by 15% (95% confidence interval 14-16%) among blacks from 18.5% to 16.2% between 1989 and 2000. Among whites, preterm birth following ruptured membranes declined by 23%, medically indicated preterm birth increased by 55%, and spontaneous preterm birth increased by 3%. Among blacks, preterm birth following ruptured membranes declined by 37%, medically indicated preterm birth increased by 32%, and spontaneous preterm birth decreased by 27%. The largest decline in perinatal mortality among whites was associated with increases in medically indicated preterm birth, whereas the largest decline in perinatal mortality among blacks was associated with declines in preterm birth following ruptured membranes and spontaneous preterm birth. CONCLUSION: Temporal trends in preterm birth varied substantially based on underlying subtype and maternal race. The recent increase in medically indicated preterm birth was associated with a favorable reduction in perinatal mortality.

Adolescent↗

Fetal transcerebellar diameter measurement with particular emphasis in the third trimester: a reliable predictor of gestational age.

OBJECTIVE: The purpose of this study was to validate prospectively a previous retrospectively established nomogram for the prediction of gestational age using transcerebellar diameter, especially in the third trimester. STUDY DESIGN: In a previous study, we retrospectively constructed a cross-sectional nomogram using transcerebellar diameter measurements in 24,026 well-dated singleton fetuses. In the present study, this nomogram was validated prospectively on the basis of patients who were seen between August 2002 and May 2003 and who were carrying non-anomalous and non-malformed singleton gestations between 14 and 42 weeks (n = 2597 gestations). The actual gestational age was then subtracted from the predicted gestational age, and the concordance between actual and predicted gestational ages was assessed based on the Pearson correlation (r). RESULTS: Concordance between the actual and predicted gestational age was high (r = 0.92; P < .0001). This agreement was superior in the second trimester (r = 0.93; P < .0001) than in the third trimester (r = 0.81; P < .001). Between 17 and 21 weeks, and between 22 and 28 weeks of gestation, the predicted gestational age ranged between 0 and 4 days, and between 0 and 2 days, respectively, of actual gestational age. Between 29 and 36 weeks of gestation, predicted gestational age was within 5 days of actual gestational age; at 37 weeks of gestation, the predicted gestational age was discrepant by 9 days. CONCLUSION: This prospective study demonstrates that transcerebellar diameter measurement is an accurate predictor of gestational age, even in the third trimester of pregnancy.

Cerebellum↗

Vasa previa: the impact of prenatal diagnosis on outcomes.

OBJECTIVE: To evaluate outcomes and predictors of neonatal survival in pregnancies complicated by vasa previa and to compare outcomes in prenatally diagnosed cases of vasa previa with those not diagnosed prenatally. METHODS: We performed a multicenter study of 155 pregnancies complicated by vasa previa. Cases were obtained from the Vasa Previa Foundation and 6 large hospitals. Comparisons were made between groups based on prenatal diagnosis status and neonatal survival. RESULTS: The overall perinatal mortality was 36% (55 of 155). In 61 cases (39%), vasa previa was diagnosed prenatally; 59 of 61 (97%) infants from these pregnancies survived compared with 41 of 94 (44%) in cases not diagnosed prenatally (P <.001). Median 1- and 5-minute Apgar scores in cases diagnosed prenatally were 8 and 9, respectively, compared with 1 and 4 among survivors in cases not diagnosed prenatally (P <.001). More than half (24 of 41) of surviving neonates born to women without prenatal diagnosis required blood transfusions compared with 2 of 59 diagnosed prenatally (P <.001). Multivariable logistic regression analysis showed that the only significant predictors of neonatal survival were prenatal diagnosis (P <.001) and gestational age at delivery (P =.01). CONCLUSIONS: Good outcomes with vasa previa depend primarily on prenatal diagnosis and cesarean delivery at 35 weeks of gestation or earlier should rupture of membranes, labor, or significant bleeding occur.

Female↗

Preterm premature rupture of membranes, intrauterine infection, and oligohydramnios: risk factors for placental abruption.

OBJECTIVE: To examine whether preterm premature rupture of membranes (PROM), intrauterine infection, and oligohydramnios are risk factors for placental abruption. METHODS: Data for this retrospective cohort study were derived from the 1988 National Maternal and Infant Health Survey (N = 11,777). Association between abruption and these clinical risk factors was expressed as relative risk (RR) and 95% confidence interval (CI), with multivariate adjustment for potential confounders. RESULTS: The overall incidence of abruption was 0.87%. The risk of abruption was 3.58-fold higher (95% CI 1.74-7.39) among women with preterm PROM (2.29%) compared with women with intact membranes (0.86%). The rates of abruption among women with and without intrauterine infection were 4.81% and 0.83%, respectively (RR 9.71, 95% CI 3.23-29.17). However, oligohydramnios was not associated with abruption (1.46% compared with 0.87%; RR 2.09, 95% CI 0.92-5.31). Compared with women with intact membranes, the RR for abruption among preterm PROM and whose membranes were ruptured for 24-47 hours and 48 hours or more before delivery, respectively, were 2.37 (95% CI 0.99-9.09), and 9.87 (95% CI 3.57-27.82). When preterm PROM was accompanied by intrauterine infections, the RR for abruption was 9.03 (95% CI 2.80-29.15) compared with women with intact membranes and no infections. Similarly, preterm PROM accompanied by oligohydramnios conferred over a 7.17-fold risk (95% CI 1.35-38.10) for abruption compared with women with neither of these 2 conditions. CONCLUSION: Women presenting with preterm PROM are at increased risk of developing abruption, with the risk being higher either in the presence of intrauterine infections or oligohydramnios. Physicians managing patients with preterm PROM should be aware that these patients are at increased risk of developing abruption after 24 hours following preterm PROM.

Abruptio Placentae↗

Total versus subtotal hysterectomy: a survey of gynecologists.

OBJECTIVE: To estimate the attitudes and practice of gynecologists in the Washington, DC, Maryland, and Virginia area regarding total versus subtotal abdominal hysterectomy. METHODS: A questionnaire with 18 questions on physicians' attitudes and practice regarding total versus subtotal hysterectomy was mailed to 1647 gynecologists in Washington, Maryland, and Virginia. RESULTS: The corrected response rate was 51.2%. Forty-five percent of respondents stated that they always removed the cervix. The most common reason cited was to eliminate the risk of cervical cancer. The most common reason for subtotal hysterectomy was surgical difficulty leading to an intraoperative change of procedure. Only 17.8% of respondents always counseled women regarding the advantages and disadvantages of both total and subtotal hysterectomy; 63% rarely or never did. Nineteen percent always offered women a choice between the procedures; 61% rarely or never did. Eighty-eight percent of respondents felt that the risk of cancer in the cervical stump was small or negligible. Gender of the physicians or year of completion of residency made no significant impact on patients being counseled about both procedures or being offered a choice between the two. CONCLUSION: Most gynecologists surveyed favor total abdominal hysterectomy over subtotal hysterectomy. Few counsel women regarding the options of total and subtotal hysterectomy or offer a choice between the procedures. Given that there are no convincing data proving the superiority of either procedure over the other, it may be reasonable to discuss the potential advantages and disadvantages of both procedures with women undergoing hysterectomy for benign disease and to offer them a choice.

Adult↗