When are amniotic fluid viral PCR studies indicated in prenatal diagnosis?

OBJECTIVE: To determine which prenatal ultrasound findings indicate the need to also obtain PCR studies for viral genome in women undergoing midtrimester amniocentesis. METHODS: This was a retrospective observational study on women that underwent amniotic fluid karyotyping and viral PCR testing for history or ultrasound based indication. Amniotic fluid was tested for adenovirus, cytomegalovirus, respiratory syncytial virus, enterovirus, Epstein-Barr virus, and parvovirus B19 using multiplex PCR study with multiple appropriate controls. Ultrasound findings were coded as normal or abnormal with 34 categories of ultrasound abnormality stratified into 18 subgroups. Relationships between these subgroups and karyotype/PCR results were tested by Pearson chi-square method or Fisher's exact test and overall logistic regression analysis. RESULTS: Amniotic fluid samples from 1191 patients were obtained for the study. Abnormal karyotype was detected in 5.4% of cases (64/1191), and PCR was positive in 6.5% of cases (77/1191). Abnormal fetal ultrasonographic findings were observed in 28.4% of cases (338/1191). There was an association between intrauterine growth restriction, nonimmune hydrops fetalis, hand/foot anomalies or neural tube defects (NTDs), and PCR positivity. NTDs were associated with PCR positivity in fetuses with normal karyotype and nuchal thickening, cardiac or ventral wall defects were specifically associated with aneuploidy. CONCLUSION: Amniotic fluid viral PCR testing should be considered for fetuses with intrauterine growth restriction, nonimmune hydrops fetalis, hand/foot anomalies, or NTDs. After aneuploidy is excluded, NTDs are associated with PCR positivity.

Laboratory testing for preeclampsia: result trends and screening recommendations.

To better direct screening for preeclampsia, we describe the result trends of the laboratory tests used in the workup of preeclampsia at our institution. The clinical characteristics of patients with abnormal test results are further detailed. The objective of the study is to recommend a laboratory screening regimen for preeclampsia based on the data. All patients who delivered at National Naval Medical Center from February to July 1996 who had blood urea nitrogen, creatinine, aspartate aminotransferase, alanine aminotransferase, or uric acid determinations as part of a workup for preeclampsia were identified. Results are reported, and the clinical characteristics of patients with abnormal tests were obtained from the medical record. Abnormalities of uric acid and liver enzymes were few in our patient population (6% and 7%, respectively). The majority of patients with abnormal uric acid and liver function tests had the classic clinical symptoms of preeclampsia; therefore, the laboratory data added little to the clinical diagnosis. There was a high rate of renal test abnormalities, necessitating further investigation. We recommend omitting liver function and uric acid testing in the routine screening for preeclampsia. The high incidence of abnormal renal tests warrants continued use of this screening test and, more importantly, further investigation into the relationship between abnormal renal tests and disease course.

Recurrent leiomyomatosis peritonealis disseminata exacerbated by in vitro fertilization.

Leiomyomatosis peritonealis disseminata is a rare disease that is most often discovered during pregnancy or in patients with a history of oral contraceptive use. We report the first case of a patient with the disease who conceived by in vitro fertilization and the complications that occurred.

Effect of meconium on the hemoglobin-oxygen association curve.

OBJECTIVE: Our purpose was to determine the effect of meconium-stained amniotic fluid on the hemoglobin-oxygen association curve of maternal whole blood. METHODS: Whole blood was obtained from term gravidas in active labor. Hemoglobin-oxygen association curves were generated for blood incubated with meconium vs. controls. Oxygen association curves were determined at pH 7.4 and 37 degrees C utilizing an automated device consisting of a spectrophotometer cuvette fitted with a magnetic stirrer, gas exchange line, and a Clark oxygen electrode. The samples were deoxygenated with nitrogen and association curves recorded while reoxygenating. Data was analyzed with Sigma Plot and Sigma Stat software. Analysis included log transformation, linear regression, and paired t-test. RESULTS: Twenty-eight hemoglobin oxygen association curves were generated. In all 14 pairs, meconium shifted the hemoglobin-oxygen association curve to the right. Partial pressures of oxygen required for various degrees of hemoglobin saturation were higher in meconium-exposed samples; P50 (30.1+/-0.6 vs. 27.8+/-0.4 mmHg, P < 0.01); P75 (46.9+/-0.6 vs. 43.1+/-0.5 mmHg, P < .001); P90 (69.2+/-1 vs. 63.3+/-1 mmHg, P < 0.01). CONCLUSIONS: Meconium-stained amniotic fluid causes a statistically significant, but clinically small, right shift in the hemoglobin-oxygen association curve.

Delaying surgery for thyroid cancer in pregnancy. A case report.

BACKGROUND: Management of thyroid cancer in pregnancy is controversial, as evidenced by disagreement in recommendations cited in leading obstetrics textbooks. Most thyroid carcinomas are well differentiated and pursue an indolent course. Many physicians recommend delay in surgical therapy until after delivery because of operative morbidity. CASE: A 27-year-old primigravida was found to have a solitary thyroid nodule at her initial obstetrics appointment. Fine needle aspiration was consistent with papillary carcinoma. Although detected at 8 weeks' estimated gestational age (EGA), the decision was made to defer surgical therapy until postpartum. The patient was referred to a tertiary care facility at 24 weeks' EGA secondary to rapid growth of the nodule. Surgery performed at that time revealed invasive disease. CONCLUSION: Review of the literature suggests that delay in definitive therapy stems from early reports of fetal loss related to surgery, but contemporary data suggest that the risk of fetal loss related to surgery is minimal.

Evaluation of routine antepartum and postpartum blood counts.

OBJECTIVE: To evaluate routine screening 28-week, admission and postpartum complete blood counts (CBCs) during a six-month period on the labor and delivery service and to correlate the laboratory data with clinical characteristics of the patients, to determine if routine CBCs are necessary in evaluating blood loss in low-risk patients and to determine whether routine admission screening for thrombocytopenia is necessary prior to epidural placement is necessary in low-risk patients. STUDY DESIGN: Laboratory data form all patients were obtained from a centralized computer system. Clinical characteristics were obtained from the medical record. RESULTS: Blood loss was determined by a change in hematocrit on admission and postpartum, and the mean of this data was used for analysis. First, the data reflected common clinical assumptions about delivery blood loss. The mean change in hematocrit for operative deliveries (7.93 +/- 5.10, 6.19 +/- 4.42; forceps and cesarean, respectively) was higher than that of spontaneous vaginal deliveries (4.31 +/- 3.78). Forcep deliveries had a larger decrease in hematocrit than repeat or primary cesarean sections combined, although it was not statistically significant (P = .04). More extensive vaginal lacerations were associated with larger decreases in hematocrit. There was a low percentage of patients requiring transfusion (1.3%) during the study period. All these patients had an estimated blood loss of > 1500 mL and delivery circumstances that would alert the clinician to the possibility of transfusion. Second, our data showed that the 28-week platelet count is predictive of the admission platelet count, with a regression coefficient of. 71. CONCLUSION: Often clinical assessment of blood loss, including history and physical examination, will predict the results of routine screening CBCs, and we question the need for routine screening of blood loss in uncomplicated deliveries. Our data on the 28-week and admission platelet counts support other authors' data showing that this screen is not necessary prior to epidural placement in low-risk patients.

The effects of atrial natriuretic factor and angiotensin II on fetal-placental perfusion pressure in the ex vivo cotyledon model.

OBJECTIVE: Our purpose was to investigate pressure changes induced by angiotensin II on placental vasculature pretreated with atrial natriuretic factor. STUDY DESIGN: A dual-perfused cotyledon model was used. Two cotyledons from each placenta were perfused. One cotyledon was infused with atrial natriuretic factor for 30 minutes while the other received an equal volume of saline solution. Three atrial natriuretic factor concentrations were studied: 50 pg/ml, 150 pg/ml, and 15 ng/ml. Both cotyledons received injections of angiotensin II, at the following doses: 1 x 10(-11.5), 1 x 10(-11), 1 x 10(-10.5), and 1 x 10(-10) mol. RESULTS: Cotyledons subjected to 50 pg/ml and 150 pg/ml concentrations of atrial natriuretic factor did not differ in pressure responses to angiotensin II, compared with the saline-infused cotyledons (p > 0.05). The 15 ng/ml concentration of atrial natriuretic factor, however, decreased the pressor response of angiotensin II (p < 0.034). CONCLUSIONS: Atrial natriuretic factor decreases vasoconstriction caused by angiotensin II. However, this was seen only at a supraphysiologic concentration. No effect was noted at normal fetal concentrations of atrial natriuretic factor.

Recurrence of Treacher Collins' syndrome with sonographic findings.

Treacher Collins' syndrome, or mandibulofacial dysostosis, is a rare, autosomal-dominant disorder. We describe the recurrence of this anomaly in the fetus of a patient who previously had delivered a severely affected infant. The ultrasonographic findings of hydramnios, absence of fetal swallowing movements, and poor growth of the biparietal diameter and head circumference permitted us to suggest the diagnosis antenatally of another affected child.

Antepartum diagnosis of arthrogryposis associated with trisomy 18.

The discovery of a fetal abnormality during ultrasonography is a widely acknowledged indication for genetic amniocentesis. We present a case in which the early diagnosis of severe arthrogryposis led to the diagnosis of trisomy 18.

Risk of chromosomal abnormalities in patients with idiopathic polyhydramnios.

This prospective investigation was designed to assess the incidence of chromosomal abnormalities in patients with idiopathic polyhydramnios. Polyhydramnios was defined as 25 cm or greater in total vertical height in all four quadrants (amniotic fluid index) in any nonreferral patient (ie, primary care population) undergoing sonographic examination with a singleton pregnancy, normal fetal anatomical survey, normal glucose screening, and negative antibody screen. During the 2-year period from May 1, 1988 through April 30, 1990, 5038 gravidas delivered at Madigan Army Hospital Center. Unexplained polyhydramnios was detected sonographically in 125 patients, an incidence of 2.5%. After obtaining informed written consent, amniocentesis was performed in all patients. Within this group (N = 125), four chromosomal abnormalities (incidence of 3.2%) were detected. There were two trisomy 18 and two trisomy 21 fetuses. None of the four patients had maternal serum alpha-fetoprotein screening performed. The incidence of aneuploidy in patients with idiopathic polyhydramnios (3.2%) is much higher than the reported incidence of major karyotype abnormalities in live births (0.59%). We conclude that fetal chromosomal analysis should be considered in all obstetric patients with sonographic evidence of idiopathic polyhydramnios.

The association of antiphospholipid antibodies with pregnancies complicated by fetal growth restriction.

The association of antiphospholipid antibodies with fetal growth restriction is often cited, but the published evidence for this is based on few patients and comes primarily from patient histories, not study groups. In this prospective study, we evaluated a subgroup of our population with fetuses whose estimated weights at ultrasound were at or below the tenth percentile for gestational age. Plasma and serum testing was performed to determine the presence of antiphospholipid antibodies, specifically lupus anticoagulant and anticardiolipin antibodies, respectively. From March 1990 through March 1991, 55 women were followed for suspected fetal growth restriction. Intensive monitoring of the fetal condition and modification of the mother's activity were recommended, resulting in 100% compliance. Despite this, 37 newborns were confirmed by birth weight to be at or below the tenth percentile, and all were below the 45th percentile. Fifteen of 55 women (27%) were positive for anticardiolipin antibodies, as were nine of 37 (24%) with correctly diagnosed fetal growth restriction. Five of 15 women whose newborns had ponderal indexes below the tenth percentile tested positive for anticardiolipin antibodies. None of the women had a positive lupus anticoagulant test. The prevalence of anticardiolipin antibodies in this study group was significantly higher than in our general population. We conclude that there is a statistically significant association between the presence of circulating maternal anticardiolipin antibodies and fetal growth restriction.

Screening for illicit drug use in a military obstetric population.

The purpose of our investigation was to determine the prevalence of illicit drug use within our socioeconomically heterogeneous obstetric population, in order to assess the need for institution of universal screening. Five hundred consecutive new obstetric registrants had urine collected for routine culture. Following removal of a small aliquot of urine for culture, the samples were sent to the Armed Forces Institute of Pathology, Division of Forensic Toxicology. Each specimen was screened for the presence of alcohol, cocaine metabolites, cannabinoids, opiates, and amphetamines using fluorescent polarization immunoassay techniques. All positive screening tests were confirmed by gas chromatography mass spectrometry. Thirty samples were either lost in processing or of insufficient quantity to test. Five of the 470 samples (1.06%) tested were positive. One subject was taking prescription narcotics, so the correlated prevalence was 0.85%. Three tested positive for tetrahydrocannabinol and two for opiates. Analysis of our data demonstrates that our obstetric population has a significantly lower prevalence of illicit drug use than other populations reported previously (P less than .01). We recommend that each institution providing obstetric services determine its specific prevalence of illicit drug use.

Hepatosplenic schistosomiasis in pregnancy: report of a case and review of the literature.

We present a report of a pregnancy complicated by chronic schistosomiasis. A.H. is a 22 year old G1 Filipina, referred at 34 weeks gestational age for evaluation of hypersplenism and progressive thrombocytopenia. Physical exam was remarkable for hepatosplenomegaly. Laboratory evaluation of hepatic, renal, hematologic, autoimmune, or infectious disease etiology or abnormality was negative. Ultrasound revealed a normal fetus, an enlarged spleen, dilated splenic and hepatic vasculature and an enlarged liver with periportal fibrosis. Abdominal computed tomography revealed subcapsular calcifications, dilated ducts, and periportal fibrosis. Esophagogastrojejeunoscopy showed no varices. The presumptive diagnosis of hypersplenism secondary to chronic hepatosplenic schistosomiasis was made. Based on pathophysiology and literature review conservative management was elected. Liver functions, clotting functions, and platelet counts were monitored closely. Intense antepartum fetal monitoring was performed. Platelet counts remained between 30 and 40K. The patient went into labor at 38 3/7 weeks and delivered a 3148 g female Apgars 8/9 by spontaneous vaginal delivery. Evaluation of the placenta was negative for ova. By 2 weeks postpartum platelet counts had increased to the 60-70 k range, and a rectal biopsy, positive for S. japonicum ova was performed. Treatment with three doses of Praziquantel 20 mg/kg q8h was completed prior to her return to the Philippines.

Vaginal breech delivery: a five-year prospective evaluation of a protocol using computed tomographic pelvimetry.

In 1983 a protocol was established at our institution that used computed tomographic pelvimetry to evaluate patients presenting with a singleton term frank breech fetus for an attempt at vaginal delivery. The criteria for a trial of labor were singleton fetus, term gestation (37 to 42 weeks' gestation from the first day of the last menstrual period), frank breech presentation, estimated fetal weight 2000 to 4000 gm, non-extended fetal head, and adequate computed tomographic pelvimetry. Two digital radiographs and a tomographic cross-section were taken of each patient, i.e., an anteroposterior view, a lateral view, and an axial section through the femoral head at the level of the fovea capitalis. Adequate pelvimetry was defined as: anteroposterior diameter of the inlet greater than or equal to 10.0 cm, transverse diameter of the inlet greater than or equal to 11.5 cm, transverse (interspinous) diameter of the midpelvis greater than or equal to 9.5 cm, and posterior sagittal diameter of the midpelvis greater than or equal to 4.0 cm. The purpose of this prospective analysis was to determine the obstetric and perinatal outcome of those breech fetuses that were evaluated with these criteria during the study period of January 1984 through July 1989. During this period the incidence of breech deliveries at our institution was 2.71% (394/14,542). Of these 394 breech deliveries, 122 patients underwent computed tomographic pelvimetry. Eighty-five patients had adequate pelvimetry, fulfilling the protocol criteria, and formed the study group. Eighty-one percent (69/85) of the study group had successful vaginal deliveries (group 1). Nineteen percent (16/85) required cesarean delivery after a trial of labor (group 2) (10 with fetal distress and six with arrested labor disorders). Of the 37 patients who had inadequate computed tomographic pelvimetry and underwent cesarean delivery without a trial of labor (group 3), 54% (20/37) had an extended fetal head, 21.6% (8/37) had an inadequate transverse diameter of the inlet, 13.5% (5/37) had an inadequate midpelvic posterior sagittal measurement, and 10.8% (4/37) had an inadequate interspinous diameter. Perinatal outcome including Apgar scores, cord gases, length of hospital stay, neonatal complications, was evaluated. No difference in infant complications was noted between the group delivered vaginally and the groups delivered abdominally. The only maternal complications in our study group were chorioamnionitis, endomyometritis, and postpartum anemia. There were no significant differences in the incidence of chorioamnionitis among the three groups of patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Randomized comparison of oral terbutaline and ritodrine for preventing recurrent preterm labor.

We compared oral ritodrine and terbutaline for the prevention of recurrent preterm labor. Women between 20 and 35 weeks' gestation who successfully completed a course of intravenous tocolysis were eligible for inclusion. One hundred two patients were randomized to oral ritodrine (20 mg every four hours) or oral terbutaline (5 mg every four hours). The groups showed no significant differences with respect to recognized risk factors for preterm labor or prognostic factors for the failure of tocolysis. Initial treatment failures occurred more frequently in the ritodrine group (nine vs. two, P = .0527). There were no statistically significant differences in the treatment results or frequency of side effects. We conclude that ritodrine appears to be less effective than terbutaline upon the initiation of oral therapy and that oral ritodrine and terbutaline are equivalent in safety and efficacy when used on a long-term basis for preventing recurrent preterm labor.