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Cande V Ananth

Publications and source records attributed to Cande V Ananth.

At least 19 recordsLinked to original sources
PubMed2006

Maternal-fetal conditions necessitating a medical intervention resulting in preterm birth.

OBJECTIVE: The objective of the study was to evaluate the extent to which maternal and fetal conditions necessitate medically indicated preterm birth. STUDY DESIGN: A population-based, retrospective, cohort study of women who delivered a singleton live birth at 20 weeks or longer in Missouri, 1989 to 1997 was performed (n = 684,711). Maternal-fetal conditions that necessitated iatrogenic preterm birth included preeclampsia, small-for-gestational-age birth, fetal distress, placental abruption, placenta previa, unexplained vaginal bleeding, pregestational and gestational diabetes, renal disease, Rh sensitization, and congenital malformations. We examined the association between each of the aforementioned conditions and risk of medically indicated preterm birth at less than 35 weeks. Medically indicated preterm birth was defined as a labor induction or a prelabor cesarean in the absence of premature rupture of membranes at preterm gestations. Adjusted relative risk with 95% confidence interval for preterm birth was derived from multivariable logistic regression models, and population attributable fractions were calculated. RESULTS: The preterm birth rate (less than 35 weeks) was 4.6% (n = 31,238), with 23.5% (n = 7,347) of such births being medically indicated. Preeclampsia, fetal distress, small-for-gestational-age, and placental abruption were the most common indications for a medical intervention resulting in preterm birth, with at least 1 of these conditions present in 53.2% of medically indicated preterm births and in 17.7% of term births (relative risk 4.9, 95% confidence interval 4.7, 5.2). CONCLUSION: Preeclampsia, fetal distress, small-for-gestational-age, and placental abruption, conditions that are associated with ischemic placental disease, are implicated in well over half of all medically indicated preterm births. Although the etiology of preterm birth is heterogeneous, it is reasonable that ischemic placental disease may serve as an important pathway to preterm birth.

Abruptio Placentae↗
PubMed2006

US Black vs White disparities in foetal growth: physiological or pathological?

BACKGROUND: Birthweight for gestational age is lower in US Black infants than in US White infants. It is unknown, however, whether this difference is 'normal' (i.e. physiological) or reflects pathological foetal growth restriction. METHODS: We applied an analytic approach based on foetuses at risk to compare gestational age-specific rates of live birth, 'revealed' small-for-gestational-age (SGA), and neonatal mortality among singleton infants >or=22 weeks of gestation and >or=500 g born in 1998-2000 to US White (n = 9 012 194), US-born Black (n = 1 554 382), and foreign-born Black (n = 200 395) mothers. Graphical methods and Cox proportional hazards regression analyses were used to compare outcomes in the three ethnic groups. RESULTS: Rates of live birth and neonatal mortality were highest at all gestational ages in US-born Blacks, lowest in Whites, and intermediate in foreign-born Blacks. The revealed SGA pattern cohered much more closely with the observed pattern for neonatal mortality when SGA was defined based on a single, overall standard of birthweight for gestational age than when based on ethnic group-specific standards. CONCLUSION: The closer coherence of revealed SGA and neonatal mortality rates based on a single standard and the intermediate pattern among foreign-born Blacks strongly suggest that Black-White differences in birthweight for gestational age are pathological, rather than physiological.

Adult↗
PubMed2006

Fetal transcerebellar diameter measurement for prediction of gestational age in twins.

OBJECTIVE: This study was undertaken to determine the accuracy of our previously published and prospectively validated institution-specific singleton transcerebellar diameter (TCD) nomogram in the prediction of gestational age (GA) in twin pregnancies. We further evaluated whether the prediction of GA in twin gestations using the singleton TCD nomogram differs between monochorionic and dichorionic twins. STUDY DESIGN: In our previously published studies, we retrospectively constructed a cross-sectional nomogram using TCD measurements in 24,026 well-dated, singleton fetuses, and prospectively validated the nomogram using 2,597 singleton fetuses. The current study comprised of 1,278 well-dated twins (19.6% monochorionic) seen in our ultrasound unit between August 1994 and May 2003, and the singleton TCD nomogram was validated in these twin gestations. The actual GA was subtracted from the GA predicted by the TCD nomogram and the concordance between actual and predicted GAs was assessed on the basis of the Pearson's correlation coefficient (r). This was performed separately for monochorionic and dichorionic twins. RESULTS: Concordance between the actual and predicted twin TCD measurements based on our previously published singleton TCD nomogram was high (Pearson's correlation, r = 0.95, P < .0001). Between 16 and 23 weeks' gestation, the predicted mean GA was within 6 days of actual GA. Between 24 and 30 weeks, the predicted mean GA was within 3 days, and at 32 weeks or more, the predicted mean GA was within 5 days of the actual GA. Prediction of GA based on the singleton TCD nomogram was equally accurate in both monochorionic and dichorionic twin gestations (P = .686). CONCLUSION: This study demonstrates that our previously validated singleton TCD nomogram is reliable and accurate in twins irrespective of placental chorionicity.

Adult↗
PubMed2006

Temporal changes in rates of stillbirth, neonatal and infant mortality among triplet gestations in the United States.

OBJECTIVE: The purpose of this study was to examine temporal changes in stillbirth, neonatal and infant mortality rates among triplet births in the US, and to assess the contributions of triplet delivery at < 34 weeks to these changes. STUDY DESIGN: Data on triplet live births, and fetal and infant deaths (1990-2002) delivered at > or = 22 weeks and fetuses weighing > or = 500 g (n = 66,986) were derived from the US linked birth/infant death data files. Relative risk (RR), quantifying changes in triplet stillbirth, neonatal (death within the first 28 days) and infant mortality (death within the first year) rates between 1990 and 1991 and 2001 and 2002, were derived. Temporal changes in triplet births at < 34 weeks, and changes in stillbirth, and neonatal and infant mortality rates were examined through logistic regression models before and after adjusting for confounders. RESULTS: Triplet births at < 34 weeks increased by 25% between 1990 and 1991 (48.7%) and 2001 and 2002 (60.9%). Stillbirth, neonatal and infant mortality rates declined by 52% (RR 0.48, 95% confidence interval [CI] 0.36-0.63), 32% (RR 0.68, 95% CI 0.58-0.80), and 38% (RR 0.62, 95% CI 0.53-0.71), respectively, between 1990 and 1991 and 2001 and 2002. The increase in triplet births at < 34 weeks was not associated with the stillbirth decline, but was associated with an excess 14% and 12% increase in neonatal and infant deaths, respectively. CONCLUSION: Our findings suggest that the increase in triplet births at < 34 weeks' gestation is not associated with changes in triplet stillbirths, but is associated with increases in triplet neonatal and infant mortality.

Female↗
PubMed2006

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↗
PubMed2006

Uteroplacental bleeding disorders during pregnancy: do missing paternal characteristics influence risk?

BACKGROUND: Several studies have assessed the risks of uteroplacental bleeding disorders in relation to maternal characteristics. The association between uteroplacental bleeding disorders and paternal characteristics, however, has received considerably less attention. Data on paternal demographics, notably race and age, from birth certificate data are becoming increasingly incomplete in recent years. This pattern of increasingly underreporting of paternal demographic data led us to speculate that pregnancies for which paternal characteristics are partially or completely missing may be associated with increased risk for uteroplacental bleeding disorders. The objective of this study is to examine the association between placenta previa and placental abruption and missing paternal age and race. METHODS: A retrospective cohort study using U.S. linked birth/infant death data from 1995 through 2001 (n = 26,336,549) was performed. Risks of placenta previa and placental abruption among: (i) pregnancies with complete paternal age and race data; (ii) paternal age only missing; (iii) paternal race only missing; and (iv) both paternal age and race missing, were evaluated. Relative risk (RR) with 95% confidence interval (CI) for placenta previa and placental abruption by missing paternal characteristics were derived after adjusting for confounders. RESULTS: Adjusted RR for placental abruption were 1.30 (95% CI 1.24, 1.37), 1.00 (95% CI 0.95, 1.05), and 1.08 (95% CI 1.06, 1.10) among pregnancies with "paternal age only", "paternal race only", and "both paternal age and race" missing, respectively. The increased risk of placental abruption among the "paternal age only missing" category is partly explained by increased risks among whites aged 20-29 years, and among blacks aged >or=30 years. However, no clear patterns in the associations between missing paternal characteristics and placenta previa were evident. CONCLUSION: Missing paternal characteristics are associated with increased risk of placental abruption, likely mediated through low socio-economic conditions.

Journal Article↗
PubMed2006

Risk factors of abruptio placentae among Peruvian women.

OBJECTIVE: We examined the relation of maternal sociodemographic, medical, and behavioral characteristics with risk of abruptio placentae in Peruvian women. STUDY DESIGN: This case-control study included 255 abruptio placentae cases and 258 pregnant controls. Multivariable logistic regression models were fit to calculate odds ratios (OR) and 95% CIs adjusted for putative abruptio placentae risk factors. RESULTS: History of delivering a stillborn infant (OR 10.0; 95%CI 4.0-25.2), pregnancy complicated by preeclampsia/eclampsia (OR 3.7; 95%CI 2.2-6.3); and a low rate of pregnancy weight gain (<0.15 kg/wk) (OR 2.5; 95%CI 1.3-4.7), were associated with significantly increased risk of abruptio placentae. Advanced maternal age, low educational attainment, male infant gender, cigarette smoking, and grand multiparty were not risk factors of abruptio placentae in this population. CONCLUSION: At present, the constellation of abruptio placentae risk factors do not provide clinically meaningful opportunities for identifying high-risk patients.

Abruptio Placentae↗
PubMed2006

Recurrence of spontaneous versus medically indicated preterm birth.

OBJECTIVE: Despite the increased tendency of preterm birth to recur, little is known with regard to recurrence risks for spontaneous and medically indicated preterm birth as well as recurrence risks in relation to severity of preterm birth. We examined the recurrence of spontaneous and medically indicated preterm birth. STUDY DESIGN: A population-based, retrospective cohort study of births in Missouri (1989 to 1997) was carried out with analyses restricted to women who delivered their first 2 consecutive singleton live births (n = 154,809). Women who experienced spontaneous onset of labor and subsequently delivered preterm (less than 35 weeks) were classified as spontaneous preterm birth. Medically indicated preterm birth included women who delivered preterm through a labor induction or a prelabor cesarean delivery. Risk and odds ratio of preterm birth recurrence were derived from fitting multivariate conditional logistic regression models after adjusting for potential confounders. RESULTS: If the first pregnancy resulted in a spontaneous preterm birth, then affected women were more likely to deliver preterm spontaneously (adjusted odds ratio 3.6, 95% confidence interval 3.2, 4.0) and also as a medically indicated preterm birth (odds ratio 2.5, 95% confidence interval 2.1, 3.0) in the second birth. Similarly, if the first pregnancy resulted in a medically indicated preterm birth, affected women were 10.6-fold (95% confidence interval 10.1, 12.4) more likely to deliver preterm because of medical indications in the second pregnancy as well as preterm spontaneously (odds ratio 1.6, 95% confidence interval 1.3, 2.1). The greatest risk of recurrence of preterm birth in the second pregnancy tended to occur around the same gestational age as preterm birth in the first pregnancy, regardless of the clinical subtype. CONCLUSION: The observation that spontaneous preterm birth is not only associated with increased recurrence of spontaneous but also medically indicated preterm birth and vice versa, suggests that the 2 clinical subtypes may share common etiologies.

Adult↗
PubMed2006

Acute and chronic respiratory diseases in pregnancy: associations with placental abruption.

OBJECTIVE: This study was undertaken to examine the associations between maternal respiratory diseases and placental abruption. STUDY DESIGN: A population-based, retrospective cohort study was conducted to examine the associations between maternal respiratory diseases and abruption in the United States. Data on women who delivered singleton births (n = 37,314,022) were derived from the National Hospital Discharge Survey for the years 1993 to 2003. International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) codes were used to identify pregnant women hospitalized for acute upper respiratory diseases, viral and bacterial pneumonia, acute bronchitis, and acute bronchiolitis, chronic bronchitis, asthma, and abruption. Relative risk (RR) and 95% CI were derived from multivariable logistic regression models to evaluate the associations after adjusting for maternal age, race, marital status, smoking, cocaine use, adequacy of prenatal care, maternal insurance status, geographic location, and year of birth (although data on smoking and cocaine use are likely underreported). RESULTS: The rate of abruption was 9.7 per 1,000 singleton births. The overall rate for acute respiratory conditions was 2.2 per 1000 pregnancies. Acute upper respiratory diseases (RR 3.2, 95% CI 3.0-3.4) and viral/bacterial pneumonia (RR 2.2, 95% CI 1.9-2.4) were associated with abruption. The rate of chronic respiratory conditions was 9.0 per 1,000 pregnancies. Chronic bronchitis was strongly associated with abruption (RR 31.8, 95% CI 29.6-34.3), but the association between asthma and abruption was modest (RR 1.1, 95% CI 1.0-1.2). Stratified analysis by maternal race showed that asthma was associated with abruption among black women but not white women. CONCLUSION: Pregnancies complicated by acute and chronic respiratory diseases requiring hospitalization are associated with placental abruption.

Abruptio Placentae↗
PubMed2006

Epidemiology of preterm birth and its clinical subtypes.

Preterm birth (<37 weeks) complicates 12.5% of all deliveries in the USA, and remains the leading cause of perinatal mortality and morbidity, accounting for as many as 75% of perinatal deaths. Despite the recent temporal increase in preterm birth, efforts to understand the problem of prematurity have met with little success. This may be attributable to the under-appreciation of the etiologic heterogeneity of preterm birth as well as the heterogeneity in its underlying clinical presentations--spontaneous onset of labor, preterm premature rupture of membranes, and medically indicated preterm birth. In this paper, we review data regarding preterm births with particular focus on its incidence, temporal trends, and recurrence. Studies of births from the USA indicate that the recent temporal increase in the overall preterm birth rate is driven by an impressive concomitant increase in medically indicated preterm birth. However, the largest temporal decline in perinatal mortality has also occurred among medically indicated preterm births (relative to other clinical subtypes), suggesting that these obstetric interventions at preterm gestational ages are associated with a reduction in perinatal mortality. Recent data indicate that spontaneous preterm birth is not only associated with increased recurrence of spontaneous, but also medically indicated, preterm birth, and vice versa. This suggests that the clinical subtypes may share common underlying etiologies. Since medically indicated preterm birth accounts for as many as 40% of all preterm births, efforts to understand the reasons for such interventions and their impact on short- and long-term morbidity in newborns is compelling. Further research is necessary in order to understand the mechanisms and etiology of preterm birth, thus leading to the possibility of effective preventive or therapeutic strategies.

Black or African American↗
PubMed2006

Risk of stillbirth following a cesarean delivery: black-white disparity.

OBJECTIVE: We examine the association between prior cesarean delivery and risk of stillbirth in a subsequent pregnancy. METHODS: The Missouri maternally linked cohort data set containing births from 1978 through 1997 was used. We identified a cohort of women who delivered live births by cesarean delivery and a comparison cohort of women who delivered live births vaginally in their first pregnancies. We then compared the risks of stillbirth in the second pregnancy between the 2 groups. RESULTS: We analyzed 396,441 women with information on first and second pregnancies, comprising 71,950 (18.1%) in the cesarean arm, and 324,491 (81.9%) in the vaginal birth arm. Rates of stillbirth among women with and those without history of cesarean delivery were 4.4 and 4.1 per 1,000 births, respectively (P = .2). The adjusted estimates also showed no difference in risk for stillbirth between the 2 groups (odds ratio [OR] 1.1, 95% confidence interval [CI] 1.0-1.3). Among whites, the stillbirth rates in women with and those without history of cesarean delivery were 3.7 and 3.6 per 1,000 births, respectively (OR 1.0, 95% CI 0.9-1.2). Among blacks, both the absolute and the adjusted relative risks for stillbirth were elevated in mothers with history of cesarean delivery (stillbirth rate 9.3 versus 6.8 per 1,000 births; OR 1.4, 95% CI 1.1-1.7). CONCLUSION: Overall, our analysis did not detect an association between cesarean history and subsequent stillbirth. However, cesarean delivery may increase the risk for subsequent stillbirth among black mothers, a group with the highest cesarean delivery rate in the country. LEVEL OF EVIDENCE: III.

Adult↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

Placental abruption in term and preterm gestations: evidence for heterogeneity in clinical pathways.

OBJECTIVE: To estimate the magnitude of associations of acute and chronic processes with abruption in preterm and term gestations. METHODS: A retrospective cohort study was performed using data on women that delivered singleton live births and stillbirths at 20 or more weeks of gestation in the United States, 1995-2002 (n = 30,378,902). Rates of 1) acute-inflammation-associated clinical conditions (premature rupture of membranes and intrauterine infection); 2) chronic processes associated with vascular dysfunction or chronic inflammation (chronic and pregnancy-induced hypertension, preexisting or gestational diabetes, small for gestational age, and maternal smoking); and 3) both acute and chronic processes, were examined among women with and without abruption. Rates were examined separately among preterm (< 37 weeks) and term births, with adjustment for confounders. Relative risk (RR) for aforementioned groups in relation to abruption was derived from multivariate logistic regression models after adjusting for potential confounders. RESULTS: At preterm gestation, the rates of acute-inflammation-associated conditions were higher among women with than without abruption (12.0% compared with 10.2%; RR 1.38, 95% confidence interval [CI] 1.34-1.42). At term, acute-inflammation-associated conditions were present in 4.2% and 3.3% of births with and without abruption, respectively (RR 1.39, 95% CI 1.33-1.45). At preterm gestation, the rates of chronic processes were 43.9% and 30.0% among women with and without abruption, respectively (RR 1.87, 95% CI 1.85-1.90). At term, the corresponding rates of chronic processes were 41.0% and 22.7%, respectively (RR 2.37, 95% CI 2.34-2.41). Association between both acute and chronic processes and abruption are similar to those of acute-inflammation-associated conditions. CONCLUSION: Among women with placental abruption, conditions associated with acute inflammation are more prevalent at preterm than term gestations, whereas chronic processes are present throughout gestation. LEVEL OF EVIDENCE: II-2.

Abruptio Placentae↗
PubMed2006

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↗
PubMed2006

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↗
PubMed2006

Risk of stillbirth in relation to maternal haemoglobin concentration during pregnancy.

The authors determined the association between maternal haemoglobin concentration measured at <28 weeks' gestation and late fetal death at >or=28 weeks' gestation (stillbirth). Data were derived from the National Maternal and Infant Health Survey--a nationally representative survey of US deliveries in 1988. Analysis was restricted to women with a singleton live birth (n = 4,199) or a stillbirth (n = 1,375) for whom maternal prenatal care, haemoglobin, smoking status and gestational age data were available. Haemoglobin concentrations during first and second trimesters, respectively, were classified as mild (10.0 to <11.0 and 9.5 to <10.5 g dL(-1)) or moderate (9.0 to <10.0 and 8.5 to <9.5 g dL(-1)) anaemia, or high haemoglobin (>or=14.6 g dL(-1) in either trimester). Hazard ratios (HR) and 95% confidence intervals (CI) for stillbirth were derived from discrete proportional hazards regression models after adjusting for confounders. Stillbirth was not associated with mild anaemia or high haemoglobin in either the first or second trimester of pregnancy. Moderate anaemia measured before 28 weeks' gestation was significantly associated with an increased risk of stillbirth among non-black women (adjusted HR: 4.4; 95% CI: 1.02, 19.01). Moderate anaemia was not associated with stillbirths among black women. Further investigation regarding causal mechanisms for this association is warranted.

Adult↗