Maternal phenylketonuria collaborative study, obstetric aspects and outcome: the first 6 years

OBJECTIVE

The purpose of this study was to evaluate the efficacy of a phenylalanine-restricted diet in reducing fetal morbidity associated with maternal hyperphenylalaninemia in women of childbearing age with blood phenylalanine levels greater than 240 mumol/L (greater than 4 mg/dl) on an unrestricted diet.

STUDY DESIGN

Two hundred thirteen pregnant women with hyperphenylalaninemia that resulted in 134 live births have been enrolled in the study. Outcome measures were subject to the chi 2 test, Fisher exact test, analysis of variance, t test, or Wilcoxon nonparametric test for analysis.

RESULTS

Optimal fetal outcome appeared to occur when blood phenylalanine levels less than 600 mumol/L (less than 10 mg/dl) were achieved by 8 to 10 weeks' gestation and maintained throughout pregnancy (trimester averages of less than or equal to 360 mumol/L (less than or equal to 6 mg/dl). Initiation of dietary therapy during the third trimester of pregnancy appears to have little beneficial effect on the fetus.

CONCLUSIONS

Preconceptual counseling and early entrance into a prenatal care program is essential in achieving optimal fetal outcome in women with hyperphenylalaninemia.

A multidisciplinary approach to the early detection of ovarian carcinoma: rationale, protocol design, and early results

OBJECTIVE

This study was undertaken to determine the feasibility of currently available tests to detect ovarian cancer at a curable stage. By studying women at risk for the disease on the basis of their family histories of cancer, we hope to gain insight into the genetics and biologic characteristics of ovarian cancer.

STUDY DESIGN

Asymptomatic women with a family history of cancer are interviewed by geneticists to obtain accurate pedigree and epidemiologic data. Screening tests including transvaginal ultrasonography, color Doppler imaging, CA 125 measurement, and other investigative biomarkers are performed between cycle days 3 and 8 and repeated biannually.

RESULTS

A total of 597 women without symptoms were screened between July 1991 and June 1992. Cystic or complex adnexal masses were detected in 6.2% of patients. A pulsatile index value < 1.0 was measured in 80% of premenopausal patients and 24% of postmenopausal patients, whereas a resistance index value < 0.4 occurred in 12% of premenopausal and 3% of postmenopausal patients. A CA 125 level > 35 U/ml was found in 11.4% of the study participants. To date, one stage IA borderline ovarian tumor and one endometrial carcinoma have been found.

CONCLUSIONS

Ovarian cancer screening needs to be investigated in a controlled fashion to determine means that will ultimately improve the survival from the disease.

Fetal choroid plexus cysts in the second trimester of pregnancy: a cause for concern

Controversy surrounds the issue of recommending cytogenetic studies in second-trimester fetuses with fetal choroid plexus cysts. To assist in clarifying this issue, a prospective study was designed to describe the association between fetal choroid plexus cysts and aneuploidy in a large population. During a 3-year period 7350 women at 15 to 22 weeks' gestation underwent an ultrasonographic evaluation. Fetal choroid plexus cysts were diagnosed in 71 (0.96%) of these pregnancies. Sixty-two of the 71 patients elected to undergo amniocentesis. An abnormal karyotype was identified in four (6.4%) of these fetuses. One fetus had trisomy 21, and three fetuses were diagnosed with trisomy 18. These data indicate that it is reasonable to offer genetic counseling and cytogenetic studies in those patients identified as having a fetal choroid plexus cyst.

The role of nonstress tests, fetal biophysical profile, and contraction stress tests in the outpatient management of insulin-requiring diabetic pregnancies

Antepartum fetal surveillance methods applicable in a home glucose-monitored population of pregnant diabetic women have been evaluated. A testing sequence of nonstress heart rate testing, backed up by either the fetal biophysical profile or contraction stress testing employed at a twice weekly interval, in 107 outpatients was compared with the management of 140 historic control patients by weekly nonstress tests and daily plasma estriols. There were 617 of 672 (91.8%) reactive nonstress tests in outpatients compared to 566 of 626 (90.4%) reactive tests in hospitalized control patients. Of 13 contraction stress tests performed in the outpatient group, only one was positive. Although 2,670 estriol determinations were done on hospitalized control patients, none was used for outpatients. No losses were attributed to unexplained antenatal stillbirth in either group. A fetal biophysical score of 8 was found to be at least as reliable as a reactive nonstress test. Antenatal surveillance in the well-controlled, insulin-requiring diabetic woman can be safely achieved with a testing sequence that consists of twice weekly nonstress tests backed up by the fetal biophysical profile and contraction stress tests.

Fetal echogenic bowel: parameters to be considered in differential diagnosis

OBJECTIVES

To evaluate the extent that associated findings aid in the differential diagnosis and/or prognosis of fetal echogenic bowel.

METHODS

Medical history, obstetric records and outcome details were examined for 131 consecutive pregnancies with fetal hyperechogenic bowel.

RESULTS

In 62 (47%) cases, there were no visible anomalies other than hyperechogenic bowel and no evidence of growth restriction. This group included four (7%) pregnancies with Down syndrome, 15 (24%) with infection or a recent episode of influenza and eight (13%) with blood staining of amniotic fluid. In the remaining 69 (53%) cases, hyperechogenic bowel was accompanied by hydrops or nuchal edema (n = 16, 12.2%), growth restriction (n = 9, 6.9%), other markers for chromosome anomalies (n = 33, 25.2%) or multiple structural anomalies (n = 11, 8.4%). In this group, the prevalence of Down syndrome was 12%, infection or influenza was reported in 14 (20%) cases and there was blood staining of amniotic fluid in seven (10%). Cystic fibrosis screening was performed in 65 (50%) pregnancies; the results were negative in all cases and clinical assessment did not indicate cystic fibrosis in any of the 91 infants who were born alive. Maternal serum screening was performed in 41 (31%) pregnancies. High alpha-fetoprotein levels were associated with multiple abnormalities or severe growth restriction.

CONCLUSIONS

In many pregnancies with fetal hyperechogenic bowel, there are multiple factors that may explain these findings. Thus identification of one potential underlying cause should not preclude further testing. Once chromosome defects, cystic fibrosis, structural abnormalities, infection and growth restriction have been excluded, parents can be counseled that the prognosis is good, irrespective of the presence or absence of blood stained amniotic fluid.

Three-dimensional ultrasonography in obstetrics and gynecology: preliminary experience

OBJECTIVE

Technologic advances in ultrasonographic imaging have revolutionized the management of women's health care. We recently began to evaluate the clinical applications of three-dimensional ultrasonography.

STUDY DESIGN

This study prospectively evaluated 161 obstetric and gynecologic patients. Both two- and three-dimensional imaging data were acquired from real-time ultrasonography. Three orthogonal planes were displayed on a monitor and were used to create the rendered three-dimensional images.

RESULTS

To date, 201 three-dimensional ultrasonographic studies have been performed, 165 transabdominally and 36 transvaginally. Transabdominally, an average of eight acquisitions per patient were obtained. Of the clinically suspected abnormalities, 29 of 32 (91%) were confirmed by three-dimensional imaging. Three of 32 (9%) improved the diagnostic capabilities or changed the diagnosis. Of the 36 transvaginal studies, an average of four acquisitions per patient were done. Thirty (83%) of these patients had suspected abnormalities and all were confirmed.

CONCLUSIONS

Three-dimensional ultrasonographic imaging appears to be highly promising in the clinical setting.

Fifteen years of experience with antepartum fetal testing

The introduction of antepartum fetal heart rate testing occurred in the very early 1970s. This article describes the evolution of testing within the Los Angeles County/University of Southern California Medical Center and encompasses a 15-year time period between 1971 and 1985. During this time approximately 200,000 patients were delivered of their infants. Fetal surveillance increased from less than 1% to current levels of 16% of patients. The antepartum fetal death rate was evaluated as a measure of evaluating the usefulness of antepartum testing. The fetal death rate after antepartum testing in selected high-risk patients was significantly less than that found in those patients not tested. The questions that might be raised regarding broader application of this technique and potential benefits are stated.

Screening for Down syndrome with the femur length/biparietal diameter ratio: a new twist of the data

OBJECTIVE

The purpose of this study was to determine the value of discordant morphometric measurements as identifiers of Down syndrome by evaluating the relationship of biparietal diameter, femur length, biparietal diameter/femur length ratio, and cephalic index between a group of fetuses with trisomy 21 and a control population.

STUDY DESIGN

Biometric measurements from 48 fetuses with trisomy were reviewed and compared with 107 normal fetuses of similar gestational age. Data were analyzed in 2-week gestational age intervals to determine the effect of gestational age on ultrasonographic detection of Down syndrome. Outcome measures were subject to least-squares linear regression and the t test for analysis.

RESULTS

A positive relationship between abnormal morphometric measurements and fetuses with Down syndrome was detected but only during specific weeks of pregnancy.

CONCLUSION

Although it appears that biometric measurements may be useful for Down syndrome, further study is needed before its widespread introduction into clinical practice.

The use of fetal echocardiography for predicting intrapartum fetal heart rate patterns in the post-term pregnancy

One of the shortcomings of antepartum testing in the post-term pregnancy is that it does not identify the majority of fetuses who develop abnormal intrapartum fetal heart rate changes. The purpose of this study was to determine whether antenatal cardiovascular evaluation could aid in the identification of post-term fetuses at risk for intrapartum heart rate abnormalities. Seventy-five patients with a gestational age greater than 41 weeks underwent a non-stress test, amniotic fluid index and real-time assessment of the heart for the presence or absence of a pericardial effusion. M-mode measurements of the right ventricular inner dimension (RVID), left ventricular inner dimension (LVID), biventricular outer dimension (BVOD) and Doppler velocimetry of the umbilical artery (S/D) were performed. Group I (n = 32) had normal intrapartum heart rate tracings. Group II (n = 20) had abnormal intrapartum fetal heart rate tracings but did not undergo emergency delivery. Group III (n = 23) had abnormal intrapartum fetal heart rate tracings but underwent emergency delivery. When comparing Group I with Group II, the latter had significant differences for abnormal RVID, RVID/LVID ratio, and pericardial effusion. When comparing Groups I and III, there were significant differences for RVID, RVID/LVID ratio, pericardial effusion, BVOD, LVID and amniotic fluid index. Neither the non-stress test nor S/D predicted abnormal intrapartum fetal heart rate patterns. For prediction of abnormal intrapartum heart rate patterns, the sensitivities of the RVID (0.79), LVID (0.33), RVID/LVID ratio (0.72) and BVOD (0.63) were 1.7-4 times greater than the non-stress test (0.19) and the sensitivities of the RVID, RVID/LVID ratio and BVOD were 2 times greater than the amniotic fluid index (0.28). The positive (0.50-0.86) and negative (0.42-0.68) predictive values were similar for all groups. To predict emergency delivery associated with abnormal heart rate tracings, the sensitivities of the RVID (0.83), RVID/LVID ratio (0.70) and BVOD (0.65) were 2.5-3 times greater than the non-stress test (0.26) and 1.5 times greater than the amniotic fluid index (0.39). The positive (0.36-0.56) and negative (0.70-0.86) predictive values were similar. The presence of pericardial effusion had a higher sensitivity than the non-stress test and amniotic fluid index for predicting abnormal intrapartum heart rate patterns but not emergency delivery. Doppler velocimetry of the umbilical artery had a lower sensitivity than the non-stress test and amniotic fluid index for predicting intrapartum heart rate patterns as well as identifying the fetus needing emergency delivery. The results of this study would suggest that there is initially dilatation of the right ventricle which may be associated with abnormal intrapartum fetal heart rate patterns. However, when the left ventricle dilates, leading to cardiomegaly, there is a greater incidence of abnormal intrapartum fetal heart rate changes and associated emergency delivery. The amniotic fluid index appears to be a later finding for predicting abnormal intrapartum fetal heart rate changes.

Selective labor induction in postterm patients. Observations and outcomes

Six hundred twenty-nine postterm patients with reliable dates were evaluated for expectant management. Patients with medical or obstetric complications, a Bishop score greater than 6 or abnormal antepartum testing were ineligible for such management. The incidences of macrosomia, fetal distress necessitating cesarean section and low five-minute Apgar scores were similar in patients with labor induction as compared to those managed expectantly. The cesarean section rate was significantly lower in patients who underwent induction for a Bishop score greater than 6 as compared to those followed expectantly (15% vs. 28%). The lowest cesarean section rate was seen in patients with Bishop scores greater than 8 (5%) versus 15% in patients with Bishop scores of 6-8.

A prospective trial of the fetal biophysical profile versus the nonstress test in the management of high-risk pregnancies

A randomized prospective trial study was developed to determine the diagnostic value of the fetal biophysical profile in relationship to the nonstress test. The diagnostic values of these tests were assessed in terms of the incidence of abnormal outcome. In addition comparisons between the positive and negative predictive values of each of these tests as well as the sensitivity and specificities of the test were reviewed. A total of 652 patients were entered into the study and a total of 1628 tests were performed. Of the group 279 pregnancies were managed by a biophysical profile protocol and 373 by the nonstress test protocol. Results of this study suggest that except for the negative predictive value in the sensitivities in the outcome parameters of low 5-minute Apgar scores the diagnostic values for all outcome parameters were consistently higher in the fetal biophysical profile as opposed to the nonstress test group. While higher, only two of the values, positive predictive value of overall abnormal outcome and negative predictive value of small for gestational age infants, were statistically significant. While this general trend suggests that the biophysical profile is more predictive in diagnosing fetal condition than the nonstress test, because statistical significance was not reached in all parameters further study is warranted.