Faculty Bibliography

INTRODUCTION/BACKGROUND:A 28-year old female presented with a non-radiating persistent left upper quadrant pain and tenderness for 5 weeks. METHODS:A preliminary CT scan displayed bony structures in the spleen. A delayed scanning subsequently showed the bones to have changed position, consistent with a life fetus. RESULTS:Ultrasound confirmed the CT findings, and ascertained the fetus to be consistent with 13 weeks of gestation. Laparoscopic splenectomy was performed and examination of the intact spleen confirmed a male fetus that was morphologically normal. CONCLUSION/CONCLUSIONS:This is the first report of fetal bony structures in the spleen associated with an advanced intra-splenic pregnancy.

PROBLEM/OBJECTIVE:Data regarding cervical interleukin 18 (IL-8) and IL-10 concentrations during pregnancy is limited. METHOD OF STUDY/METHODS:This was a cross sectional study of healthy pregnant women. Specimens were collected from the cervical os secretions. IL-8 and IL-10 levels were measured by using enzyme-linked immunosorbent assay. Median (range) cytokine concentrations were derived for each trimester and compared across trimesters. The relationship between gestational age and cytokine levels was assessed by regression analysis. The mean of the ratios of IL-8 to IL-10 was compared in each trimester using anova. RESULTS:The median (range) IL-8 concentrations in cervical secretions were in pg/mL: 1562 (1210-4100), 2460 (1047-4688), 3660 (1451-4748) (P < 0.0021); the median (range) IL-10 concentrations in cervical secretions were in pg/mL: 38.3 (6.8-227.9), 10.9 (0-263.3), 9.5 (0-35.6); the mean IL10/IL-8 x 100 (+/- standard deviation) concentrations were: 3.33 +/- 0.65, 1.47 +/- 0.41, 0.38 +/- 0.52 (P = 0.0035) during the first, second and third trimesters, respectively. CONCLUSION/CONCLUSIONS:The patterns of cervical IL-8 concentration is inversely related to gestational age, and the ratio of IL-10/IL-8 decreases with advancing gestation.

OBJECTIVE: To test the hypothesis that the presence of preeclampsia, small for gestational age (SGA)-birth, and placental abruption in the first pregnancy confers increased risk in the second pregnancy. METHODS: A retrospective cohort study entailing a case-crossover analysis was performed based on women who had two consecutive singleton live births (n=154,810) between 1989 and 1997 in Missouri. Small for gestational age was defined as infants with birth weight below the 10th centile for gestational age. Risk and recurrence of ischemic placental disease was assessed from fitting logistic regression models after adjusting for several confounders. RESULTS: Preeclampsia in the first pregnancy was associated with significantly increased risk of preeclampsia (odds ratio 7.03, 95% confidence interval 6.51, 7.59), SGA (odds ratio 1.16, 95% confidence interval 1.06, 1.27), and placental abruption (odds ratio 1.90, 95% confidence interval 1.51, 2.38) in the second pregnancy. Similarly, women with SGA and abruption in the first pregnancy were associated with increased risks of all other conditions in the second pregnancy. CONCLUSION: Women with preeclampsia, SGA, and placental abruption in their first pregnancy--conditions that constitute ischemic placental disease--are at substantially increased risk of recurrence of any or all these conditions in their second pregnancy. Although causes of these conditions remain largely speculative, these entities may manifest through a common pathway of ischemic placental disease with significant risk of recurrence.

OBJECTIVE: The purpose of this study was to determine the accuracy of our previously published and prospectively validated transcerebellar diameter (TCD) nomogram in the prediction of gestational age (GA) in intrauterine growth-restricted (IUGR) and large fetuses. METHODS: We established a cross-sectional nomogram of TCD in 24,026 well-dated singleton fetuses and prospectively validated the nomogram using 2597 fetuses from a separate population. This nomogram was validated in both IUGR (n = 55) and large (n = 16) fetuses (estimated fetal weight, <10th and >90th percentiles, respectively). The actual GA was subtracted from the TCD-predicted GA in IUGR and large fetuses, and the concordance between the actual and predicted GAs was assessed using the Pearson correlation coefficient. RESULTS: Concordance between the actual and predicted GA based on our previously published singleton TCD nomogram was high for both IUGR and large fetuses (Pearson correlation, r = 0.98 and 0.95, respectively; P < .001). The means (SDs) of actual and predicted GA based on TCD in IUGR fetuses were 24.9 (6.5) and 25.1 (6.3) weeks, respectively. The predicted GA based on TCD in IUGR fetuses was within 3 days in 97.5% in the second trimester and 93.3% in the third trimester. In large fetuses, the difference between the actual and predicted GA based on TCD within 3 days was 100% in both the second and third trimesters. CONCLUSIONS: This study shows that our institution-specific TCD nomogram is reliable and accurate in predicting GA even at extremes of fetal growth.

OBJECTIVE:This study was undertaken to examine the associations between maternal respiratory diseases and placental abruption. STUDY DESIGN/METHODS: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/CONCLUSIONS:Pregnancies complicated by acute and chronic respiratory diseases requiring hospitalization are associated with placental abruption.

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/CONCLUSIONS:Missing paternal characteristics are associated with increased risk of placental abruption, likely mediated through low socio-economic conditions.

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/CONCLUSIONS: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.

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.

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/METHODS: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/CONCLUSIONS: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.

OBJECTIVE:The objective of the study was to evaluate the extent to which maternal and fetal conditions necessitate medically indicated preterm birth. STUDY DESIGN/METHODS: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/CONCLUSIONS: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.