R W Zingheim

Swedish Medical Center Seattle, Seattle, WA, United States

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Publications (24)60.98 Total impact

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    ABSTRACT: Our goal was to lower unplanned primary cesarean deliveries by reducing elective inductions. To implement and sustain an induction management program, a committee of care providers reviewed induction rates. "Elective" and other categories were defined. An induction consent form was drafted. Consent compliance, induction rates, hours in labor and delivery and mode of delivery were evaluated. Outcomes were compared with historical data from 2 years earlier. A total of 10,166 nulliparas and 9869 multiparas attempted vaginal deliveries. Elective inductions decreased significantly, from 4.3% to 0.8% in nulliparas and from 13% to 9.5% in multiparas. A longer time to delivery was seen for both nulliparas (5.2 hours) and multiparas (4 hours) with elective inductions. Unplanned primary cesarean delivery rates are significantly lower in spontaneously laboring women, compared with those induced. A program aimed at reducing elective inductions was successfully implemented and sustained.
    American journal of obstetrics and gynecology 05/2009; 200(6):674.e1-7. · 3.28 Impact Factor
  • David A Luthy, Judith A Malmgren, Rosalee W Zingheim
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    ABSTRACT: The purpose of this study was to assess the contribution of the individual physician to the probability of cesarean delivery among nulliparous women who undergo elective induction. A cohort study compared spontaneous labor and elective induction for all term, singleton, and cephalic nulliparous gestations over 2 years (1999-2000) at a large metropolitan hospital (n = 3215). Bivariate analysis was used to identify significant variables that were related to cesarean delivery. Logistic regression analysis was used to calculate the adjusted risk of cesarean delivery and to assess the independent effect of individual physician practice on cesarean delivery. Physician effect was evaluated in terms of its relative contribution to the explanatory power of the logistic regression model to predict cesarean delivery. The adjusted odds ratio for cesarean delivery with elective induction was 1.78 (95% CI, 1.39, 2.27). Using forward stepwise regression, the individual physician was a significant independent risk factor in the model with an R square statistic increase from 0.194 to 0.249 when the physician statistic was added to the final model. Nulliparous women are at a significant increased risk of cesarean delivery if elective induction is performed. The individual physician has a contributing effect to this increased risk.
    American Journal of Obstetrics and Gynecology 12/2004; 191(5):1511-5. · 3.88 Impact Factor
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    ABSTRACT: The purpose of this study was to assess the contribution of physician management to the probability of cesarean delivery. A prospective cohort study was performed of all live births who weighed > or =500 g for a 2-year period (1999-2000) at a large metropolitan hospital (n = 10,027 births). Factors that were associated significantly with cesarean delivery at one time excluded cases in which cesarean delivery was a necessary or probable outcome. In the planned vaginal delivery sample (n = 7940 births), a risk-adjusted logistic regression model was used to assess the prediction of cesarean delivery. To test for the effect of physician-management physician, we used the subset of physicians with > or =45 deliveries in the 2-year time period (n = 6563 deliveries). When physician-management physician data were added to the use of forward stepwise regression, entry order was abnormal position, nulliparity, birth weight of >4000 g, and physician. The model's predictive ability improved from 43.8% to 50.2%. Physician management adds a significant independent effect to the cesarean delivery risk model.
    American Journal of Obstetrics and Gynecology 06/2003; 188(6):1579-85; discussion 1585-7. · 3.88 Impact Factor
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    ABSTRACT: This study was undertaken to evaluate a group B streptococcal protocol in a large community hospital that combined treatment of high-risk patients with rapid screening of low-risk patients. In a prospective cohort study from 1994 through 1996 laboring patients in a level III community hospital were considered to be at high risk for neonatal group B streptococcal transmission if they were at <37 weeks' gestation, if they had rupture of membranes >12 hours, if they were known carriers of group B streptococci, if they had a temperature > or =100 degrees F, if the gestation was complicated by fetal growth restriction or was a multiple gestation, or if they had a previous neonate infected with group B streptococci. High-risk patients were treated intravenously with antibiotics during labor. Low-risk patients were screened for group B streptococcal antigen by means of a rapid optical immunoassay. Patients with positive screening results were treated. Neonatal morbidity and mortality were evaluated. Two of 9932 infants delivered had group B streptococcal sepsis diagnosed. In the 2 previous years without a protocol 9 cases of neonatal group B streptococcal sepsis had been diagnosed in 8188 deliveries (P =.0287 by Fisher exact test). The 2 cases of group B streptococcal sepsis during the protocol were as follows: 1 infant born to a high-risk mother with delay in treatment and 1 infant born to a low-risk mother with negative results of both culture and rapid screen during labor. During the previous period 7 infected infants had been born to high-risk mothers and 2 had been born to low-risk mothers. The maternal group B streptococcal carriage rate during the study was 18%. Group B streptococcal rapid optical immunoassay sensitivity was 81%. Elapsed time from screening to treatment was < or =2(1/2) hours for 93% of patients. No maternal anaphylaxis, no increase in bacterial neonatal sepsis caused by organisms other than group B streptococci, and no protocol-related group B streptococcal antibiotic resistance were noted. Successful implementation and maintenance of a protocol combining treatment of high-risk patients with rapid screening of low-risk patients during labor reduced neonatal group B streptococcal sepsis.
    American Journal of Obstetrics and Gynecology 06/2000; 182(6):1335-43. · 3.88 Impact Factor
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    ABSTRACT: The adipocyte hormone, leptin, is secreted in proportion to adipose mass and is implicated in the regulation of energy balance via its central actions on food intake and sympathetic nervous system activity. The placenta was also shown recently to be a possible source of leptin in pregnant women, raising the possibility that the normal relationship between leptin and adiposity may be altered in pre-eclampsia. We therefore sought to assess the extent to which maternal second trimester serum leptin concentrations differed for women who would subsequently develop pre-eclampsia and those who would remain normotensive. This nested case-control study population comprised 38 women with pregnancy-induced hypertension and proteinuria (pre-eclampsia) and 192 normotensive women. Multiple least-squares regression procedures were used to assess the independent relationship between leptin concentrations and risk of pre-eclampsia. Serum leptin concentrations, measured by radioimmunoassay, were highly correlated with maternal pre-pregnancy and second trimester body mass index (r = 0.71 and r = 0.74 respectively; P < 0.001 for both) among normotensive women, and to a lesser extent among women who developed pre-eclampsia (r = 0.29 and r = 0.42; P = 0.09 and 0.02 respectively). Among women with a pre-pregnancy body mass index of < or = 25 kg/m2, pre-eclampsia cases compared with controls had higher mean second trimester leptin concentrations after adjustment for confounding factors. In contrast, pre-eclampsia cases had lower mean leptin concentrations than controls for those women with a pre-pregnancy body mass index above 25 kg/m2. Other factors in addition to the level of adiposity may therefore influence serum leptin concentrations in pre-eclamptic pregnant women. Our results suggest the possibility that leptin, like several other placentally derived substances (e.g. steroid hormones, eicosanoids and cytokines), may be involved in the pathogenesis of pre-eclampsia. Further work is needed to confirm our findings and to assess the metabolic importance and determinants of leptin concentrations in uncomplicated and pre-eclamptic pregnancies.
    Paediatric and Perinatal Epidemiology 04/1999; 13(2):190-204. · 2.16 Impact Factor
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    ABSTRACT: Preeclampsia is characterized by diffuse vascular endothelial dysfunction. Tumor necrosis factor-α (TNF-α), which plays a key role in the cytokine network responsible for immunoregulation, is also known to contribute to endothelial dysfunction and other metabolic disturbances noted in preeclampsia. Results from cross-sectional studies and one longitudinal study indicate that TNF-α (or its soluble receptor, sTNFp55) is increased in the peripheral circulation and amniotic fluid of women with preeclampsia as compared with normotensive women. Between December 1993 and August 1994, prediagnostic sTNFp55 concentrations (a marker of excessive TNF-α release) were measured in 35 women with preeclampsia and 222 normotensive women to determine whether elevations precede the clinical manifestation of the disorder. Logistic regression procedures were used to calculate maximum likelihood estimates of odds ratios and 95&percnt; confidence intervals. Mean second trimester (15–22 weeks' gestation) serum sTNFp55 concentrations, measured by enzyme-linked immunosorbent assay, were 14.4&percnt; higher in preeclamptic women than in normotensive controls (716.6 pg&sol;ml (standard deviation 193.6) vs. 626.4 pg&sol;ml (standard deviation 158.0); p &equals; 0.003). The relative risk of preeclampsia increased across successively higher quintiles of sTNFp55 (odds ratios were 1.0, 1.3, 2.1, and 3.7, with the lowest quintile used as the referent; p for trend &equals; 0.007). After adjustment for maternal age, adiposity, and parity, the relative risk between extreme quintiles was 3.3 (95&percnt; confidence interval 0.8–13.4). These findings indicate that the level of TNF-α in maternal circulation is increased prior to the clinical manifestation of the disorder, and they are consistent with the hypothesized role of cytokines in mediating endothelial dysfunction and the pathogenesis of preeclampsia. Further work is needed to identify modifiable risk factors for the excessive synthesis and release of TNF-α in pregnancy, and to assess whether lowering of TNF-α concentrations in pregnancy alters the incidence and severity of preeclampsia. Am J Epidemiol 1999; 149: 323–9.
    American Journal of Epidemiology 03/1999; · 4.78 Impact Factor
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    ABSTRACT: Trans fatty acids, formed by the partial hydrogenation of vegetable oils, are associated with increases in plasma concentrations of cholesterol, triglyceride, lipoprotein (a), and coronary heart disease risk. Trans fatty acids may also increase platelet aggregation and alter eicosanoid biosynthesis. We studied the relation between maternal dietary intake of trans fatty acids and risk of preeclampsia. Maternal intake of elaidic acid, one of the most abundant dietary trans fatty acids and other fatty acids were estimated using gas-liquid chromatography on erythrocytes from 22 women with preeclampsia and 40 normotensive controls. Fatty acids were expressed as the percentage of total fatty acids in erythrocytes. Logistic regression procedures were used to estimate odds ratios and 95% confidence intervals. Mean levels of elaidic acid were 28% higher among preeclamptics (0.43 +/- 0.12) as compared with controls (0.31 +/- 0.12; p < 0.001). After adjusting for confounding factors, women with the highest levels of elaidic acid (median = 0.47) were 7.4 times (odds ratio = 7.4; 95% confidence interval 1.4-39.7) more likely to have had their pregnancy complicated by preeclampsia as compared with those women with the lowest levels (median 0.24). Risk of preeclampsia appeared to increase with increasing levels of elaidic acid (p value for linear trend = 0.05). These cross-sectional data suggest that diets high in elaidic acid may be associated with an increased risk of preeclampsia. This hypothesis should be examined in larger longitudinal studies.
    Gynecologic and Obstetric Investigation 08/1998; 46(2):84-7. · 1.10 Impact Factor
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    ABSTRACT: Elevated maternal serum human chorionic gonadotropin (hCG) is an important marker of Down syndrome. Notably, women with unexplained elevated serum hCG in the second trimester experience a 2- to 5-fold increase risk of preeclampsia. Urinary gonadotropin peptide (UGP), thought to be a metabolite of hCG that is excreted into urine, has recently been shown to be elevated in Down syndrome pregnancies. We sought to examine urinary UGP levels in preeclamptic and normotensive pregnant women. We measured UGP levels in urine collected during the third trimester from 18 women with preeclampsia and 20 normotensive controls. UGP levels were determined using enzyme immunoassay and were corrected for dilution using urinary creatinine. Statistical significance testing was done using the Wilcoxon-Mann-Whitney Rank Sum test and Student t test statistics. There was a statistically significant elevation in urinary UGP levels among preeclamptic cases as compared to normotensive control subjects (p = 0.013). Mean urinary UGP levels were 80.7 and 31.3 pmol/mg creatinine for preeclampsia cases and controls, respectively. Elevations in UGP levels among women with preeclampsia as compared with normotensive control subjects persisted after adjustments for possible confounding factors. These early findings suggest that elevations in urinary UGP may be a risk marker for preeclampsia. Prospective studies should further clarify the relation between urinary UGP levels and adverse pregnancy outcomes. These results are consistent with results suggesting a role of placental hypoperfusion in the etiology of preeclampsia.
    Gynecologic and Obstetric Investigation 02/1998; 45(1):24-8. · 1.10 Impact Factor
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    ABSTRACT: Objective: Elevated maternal serum human chorionic gonadotropin (hCG) is an important marker of Down syndrome. Notably, women with unexplained elevated serum hCG in the second trimester experience a 2- to 5-fold increase risk of preeclampsia. Urinary gonadotropin peptide (UGP), thought to be a metabolite of hCG that is excreted into urine, has recently been shown to be elevated in Down syndrome pregnancies. We sought to examine urinary UGP levels in preeclamptic and normotensive pregnant women. Methods: We measured UGP levels in urine collected during the third trimester from 18 women with preeclampsia and 20 normotensive controls. UGP levels were determined using enzyme immunoassay and were corrected for dilution using urinary creatinine. Statistical significance testing was done using the Wilcoxon-Mann-Whitney Rank Sum test and Student t test statistics. Results: There was a statistically significant elevation in urinary UGP levels among preeclamptic cases as compared to normotensive control subjects (p = 0.013). Mean urinary UGP levels were 80.7 and 31.3 pmol/mg creatinine for preeclampsia cases and controls, respectively. Elevations in UGP levels among women with preeclampsia as compared with normotensive control subjects persisted after adjustments for possible confounding factors. Conclusion: These early findings suggest that elevations in urinary UGP may be a risk marker for preeclampsia. Prospective studies should further clarify the relation between urinary UGP levels and adverse pregnancy outcomes. These results are consistent with results suggesting a role of placental hypoperfusion in the etiology of preeclampsia.
    Gynecologic and Obstetric Investigation - GYNECOL OBSTET INVEST. 01/1998; 45(1):24-28.
  • American Journal of Obstetrics and Gynecology - AMER J OBSTET GYNECOL. 01/1997; 176(1).
  • American Journal of Obstetrics and Gynecology - AMER J OBSTET GYNECOL. 01/1997; 176(1).
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    ABSTRACT: Preeclampsia is a systemic disease characterized by diffuse endothelial dysfunction, increased peripheral vascular resistance, coagulation abnormalities, antioxidant deficiency, persistent elevations of maternal leukocyte-derived cytokines, and hyperlipidemia. Fish oil, rich in omega-3 polyunsaturated fatty acids, is known to reduce fasting and postprandial triglycerides and to decrease platelet and leukocyte reactivity; it may also decrease blood pressure. Additionally, omega-3 fatty acids may beneficially influence vessel wall characteristics and blood rheology. In light of the potential beneficial effects of dietary omega-3 fatty acids, we conducted a cross-sectional case-control study to examine the hypothesized exposure-effect relation between maternal dietary intake of marine omega-3 fatty acids and risk of preeclampsia. We measured polyunsaturated fatty acids in erythrocytes obtained from 22 preeclamptic women and 40 normotensive women; we measured polyunsaturated fatty acids as the percentage of total fatty acids from gas chromatography. We employed logistic regression procedures to estimate odds ratios (ORs) and 95% confidence intervals (CIs). After adjusting for confounders, women with the lowest levels of omega-3 fatty acids were 7.6 times more likely to have had their pregnancies complicated by preeclampsia as compared with those women with the highest levels of omega-3 fatty acids (95% CI = 1.4-40.6). A 15% increase in the ratio of omega-3 to omega-6 fatty acids was associated with a 46% reduction in risk of preeclampsia (OR = 0.54; 95% CI = 0.41-0.72). Low erythrocyte levels of omega-3 fatty acids and high levels of some omega-6 fatty acids, particularly arachidonic acid, appear to be associated with an increased risk of preeclampsia.
    Epidemiology 06/1995; 6(3):232-7. · 5.74 Impact Factor
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    ABSTRACT: To determine if pregnant women with normal singletons will continue to have elevated serum human chorionic gonadotropin (hCG), given that they had an elevated serum hCG in the second trimester. Nineteen women with second-trimester hCG levels > or = 2.0 multiples of the median, and 20 women with second-trimester hCG levels < 2.0 multiples of the median were the subjects of this investigation. All study participants had serum hCG levels repeated during the third trimester of pregnancy. We used a chi-square test and Student's t test for comparing categorical variables, and the means of continuous variables, respectively. Using the criterion of > or = 2.0 multiples of the median of the comparison group to define hCG elevation, women with elevated second-trimester hCG levels were women with normal second-trimester hCG levels (risk ratio = 3.9; 95% confidence interval 1.6-9.8; p < 0.001). Adjustment for potential confounders did not materially alter the association. Women with elevated hCG in the second trimester continued to have elevations in the third trimester. The persistence of elevated hCG levels in pregnancies uncomplicated by fetal anomalies should be evaluated as a clinical marker of adverse pregnancy outcomes.
    Gynecologic and Obstetric Investigation 01/1995; 40(3):158-61. · 1.10 Impact Factor
  • Epidemiology. 01/1995; 6(3):232-237.
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    ABSTRACT: The objective of the study was to evaluate the efficacy and safety of preinduction cervical ripening with 0.5 mg of intracervical prostaglandin E2 (PGE2) gel in women with a previous cesarean section. A retrospective cohort study design was used to compare 117 women with one previous cesarean section (VBACS) with 354 nulliparas. Both groups received preinduction cervical ripening treatment with intracervical PGE2 gel. Student's t and chi 2 tests were used to evaluate group differences. Mantel-Haenszel summary risk ratios and 95% confidence intervals were examined in order to assess the relative risk of cesarian section delivery after adjusting for potential confounders. The mean numbers of PGE2 gel applications were 2.4 and 2.5 for VBACS and controls, respectively (p < 0.05). Thirty-nine percent of VBACS entered labor spontaneously as compared with 33% of nulliparas. Mean duration of ruptured membranes (8.2 vs. 12.1 h) and length of labor (20.1 vs. 28.5 h) were reduced among VBACS as compared with controls (p < 0.05). Overall, VBACS had a higher cesarean section rate as compared with controls (49.6 vs. 31.9%; adjusted relative risk = 1.6, 95% confidence interval 1.2-2.1). There were no differences in the occurrence of maternal and fetal morbidity. Overall, the efficacy and safety of 0.5 mg PGE2 gel administered for preinduction cervical ripening in VBACS is comparable to that observed in nulliparas.
    Gynecologic and Obstetric Investigation 01/1995; 40(2):89-93. · 1.10 Impact Factor
  • American Journal of Obstetrics and Gynecology - AMER J OBSTET GYNECOL. 01/1995; 172(1):324-324.
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    ABSTRACT: To evaluate measurements of maternal serum CA 125 for the diagnosis of abruptio placentae. This investigation was conducted at Swedish Medical Center/Seattle from December 1991 through April 1992. During the study period, we identified 21 consecutive patients with a clinical diagnosis of abruptio placentae. In addition, we enrolled two groups of patients whose pregnancies were not complicated by placental abruption (28 preterm controls and 53 term controls). Mean maternal serum levels of CA 125 were significantly higher among women with abruptio placentae (40.6 +/- 29.6 U/mL) than among preterm controls (26.6 +/- 17.2 U/mL) or term controls (22.0 +/- 11.4 U/mL). Using a positive threshold of 35 U/mL, the sensitivity and specificity of maternal serum CA 125 for abruptio placentae were 42.9% (95% confidence interval [CI] 21.7-64.1) and 92.5% (95% CI 85.4-99.6), respectively. These findings support an earlier report documenting higher mean maternal serum levels of CA 125 among women with pregnancies complicated by abruptio placentae than in control subjects. However, measurement of maternal serum CA 125 does not appear to be a useful marker for the diagnosis of abruptio placentae. At present, clinical diagnosis of abruptio placentae, with the aid of ultrasonography to rule out other causes of late gestational hemorrhage, should be considered the most sensitive and specific method of detecting this pregnancy complication.
    Obstetrics and Gynecology 12/1993; 82(5):808-12. · 4.80 Impact Factor
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    ABSTRACT: Our purpose was to further evaluate the role of serial amniocentesis in pregnancies complicated by the "stuck twin" syndrome. A cohort of 37 consecutive cases of stuck twin syndrome was followed up from 1986 through 1992. Evaluations included gestational age at diagnosis and at delivery, mean number of amniocenteses, volume of amniotic fluid withdrawn, placentation, perinatal complications, fetal survival, and neonatal follow-up. Five pregnancies were terminated, five had no intervention, and 27 underwent serial amniocenteses. The mean number of amniocenteses was 3.4 (range 1 to 6), and mean total amniotic fluid volume withdrawn was 5.8 L (range 0.75 to 4.0). In the serial amniocentesis group mean gestational age was 23.1 weeks (range 16 to 30) at diagnosis and 31.5 weeks (range 20 to 38) at delivery. Eighty-two percent had monochorionic placentas, and 36% had marginal or velamentous cord insertions. Infant survival was 39 of 54 (74%) in the serial amniocentesis group compared with four of 10 (40%) in the nonintervention group (relative risk 0.46, 95% confidence interval 0.24 to 0.90). Serial amniocentesis was associated with a 54% reduction in fetal and neonatal death in cases of stuck twin syndrome.
    American Journal of Obstetrics and Gynecology 11/1993; 169(4):991-5. · 3.88 Impact Factor
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    ABSTRACT: Pregnancy-induced hypertension is believed to be a disorder of the vascular endothelium, possibly focused in the placenta. Markers such as cellular fibronectin appear early in patients in whom pregnancy-induced hypertension develops. We hypothesized that patients with elevated second-trimester levels of human chorionic gonadotropin would have an increased risk for pregnancy-induced hypertension. We conducted a cohort study, using a database of patients undergoing second-trimester serum screening for Down syndrome and who were delivered at our institution between January 1990 and August 1991. We included all 180 women with human chorionic gonadotropin levels > or = 2.0 multiples of the median. A sequential sample of 369 women with levels < 2.0 multiples of the median served as the referent group. Standard American College of Obstetricians and Gynecologists definitions of pregnancy-induced hypertension and proteinuria were used. Patients with elevated human chorionic gonadotropin levels were at increased risk for pregnancy-induced hypertension (risk ratio 1.7, 95% confidence interval 1.2 to 2.4) and proteinuric pregnancy-induced hypertension (risk ratio 5.1, 95% confidence interval 1.6 to 16.2). Adjusting for potential confounding factors did not alter these associations. Patients with elevated human chorionic gonadotropin appear to be at higher risk of pregnancy-induced hypertension and proteinuric pregnancy-induced hypertension. Second-trimester human chorionic gonadotropin levels should be further investigated as a potential marker for pregnancy-induced hypertension.
    American Journal of Obstetrics and Gynecology 11/1993; 169(4):834-8. · 3.88 Impact Factor
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    ABSTRACT: Unexplained elevations in maternal serum alpha-fetoprotein in the midtrimester are associated with adverse pregnancy outcome. Recently it has also been suggested that elevations of maternal serum human chorionic gonadotropin in the second trimester may be associated with adverse pregnancy outcome. We conducted a cohort study of 460 women at Swedish Medical Center, Seattle, Washington, between Jan. 1, 1990, and Aug. 15, 1991, inclusive. Entry criteria for the cohort included (1) triple screen analysis (maternal serum alpha-fetoprotein, human chorionic gonadotropin, unconjugated estriol) between 15 and 18 weeks' gestation, (2) a risk for Down syndrome of more than one in 195 on the basis of triple screen analysis, (3) study group human chorionic gonadotropin > or = 2 multiples of the median and referent group < or = 2 multiples of the median, alpha-fetoprotein < or = 2 multiples of the median, unconjugated estriol > or = 0.5 multiples of the median, and (4) chromosomally normal single gestation without anomalies. Cumulative incidence risk ratios were estimated for each pregnancy outcome as a measure of the relative association with elevated human chorionic gonadotropin (> or = 2.0 multiples of the median) and adverse pregnancy outcome: low birth weight, < or = 2500 gm; preterm delivery, < 37 weeks' gestation; and small for gestational age, < or = 10th percentile. The Mantel extension test was used to evaluate any apparent linear trend in risk between level of human chorionic gonadotropin and adverse pregnancy outcome. Elevated human chorionic gonadotropin levels were associated with an increased risk for low birth weight (relative risk = 4.0), preterm delivery (relative risk = 2.8), and small for gestational age (relative risk = 1.8). The risk for each adverse outcome increased with increasing levels of human chorionic gonadotropin. Elevations of human chorionic gonadotropin in the midtrimester appear to be associated with adverse pregnancy outcome. The magnitude of the risk correlates with the level of human chorionic gonadotropin. This risk appears to be independent of the risk for adverse pregnancy outcome associated with unexplained elevations of maternal serum alpha-fetoprotein.
    American Journal of Obstetrics and Gynecology 06/1993; 168(6 Pt 1):1852-6; discussion 1856-7. · 3.88 Impact Factor