Treatment of twin-twin transfusion syndrome.

OBJECTIVE: To determine whether therapeutic amniocentesis may improve outcomes in patients with twin-twin transfusion syndrome. METHODS: Thirteen patients with possible twin-twin transfusion syndrome were evaluated for treatment. Therapeutic amniocenteses were performed on nine, and four patients were managed conservatively depending on the clinical severity of the twin-twin transfusion syndrome. RESULTS: Therapeutic amniocenteses resolved the syndrome in three of nine cases, with an overall neonatal survival rate of 83.3% (15 of 18) and neonatal morbidity of 53.3% (eight of 15) among the survivors. The survival rate in patients with expectant management was 75% (six of eight), with a neonatal morbidity of 33.3% (two of six). An association between amniotic fluid status and fetal outcomes was observed. Patients with normalization of polyhydramniosoligohydramnios had the best outcomes. CONCLUSION: Early, aggressive amniocentesis may be an effective therapy for twin-twin transfusion syndrome. Therapeutic amniocentesis may have the capability to alter inter-fetal blood flow, possibly as a result of changes in intravascular pressure, which are related to changes in intra-amniotic pressure.

Maternal smoking and accelerated placental maturation.

In a prospective study of 367 patients referred for obstetric ultrasound evaluation, maternal cigarette smoking was found to have an important effect on the rate of placental maturation. The frequencies of grades 0, I, II, and III placentas throughout gestation were determined for both smoking and nonsmoking groups. Overall, the smoking mothers had more mature placentas than the nonsmoking mothers. This was reflected by the earlier mean gestational age at appearance of each of the placental grades in the smoking group as compared with the nonsmoking group. The mean gestational ages at appearance of grades 0, I, II, and III placentas for smoking mothers were 23.5, 27.9, 32, and 34.4 weeks, respectively, as compared with 26, 31.6, 35.7, and 38.3 weeks in the nonsmoking group. Smokers had a greater frequency of grade II placentas from 22-35 weeks than nonsmokers, and a greater frequency of grade III placentas beyond 25 weeks.

Obstetrical applications of computer technology.

Computer technology and the use of personal computers in obstetrics, particularly antepartum, and intrapartum fetal evaluation, are discussed. The future direction of computer technology in fetal assessment is also addressed.

Vaginal birth after Cesarean rates are declining rapidly in the rural state of Maine.

OBJECTIVE: The American College of Obstetricians and Gynecologists (ACOG) revised its practice bulletin on vaginal birth after Cesarean (VBAC) in October 1998 and July 1999 to require the presence of a surgeon, anesthesiologist and operating personnel throughout the trial of labor for patients with prior Cesarean. This study measures the change in VBAC rates from 1998 to 2001 and examines possible reasons for this change. STUDY DESIGN: We examined birth certificate and hospital data in the State of Maine from 1998 to 2001. Hospital-specific rates for primary Cesareans, total Cesareans, repeat Cesareans and vaginal deliveries after previous Cesarean were obtained. Additionally, we surveyed current obstetric-care providers in Maine regarding reasons for change in VBAC rates at their institutions. RESULTS: VBAC rates declined by over 50% from 30.1 to 13.1%. The total Cesarean rate climbed from 19.4 to 24.0%. The most commonly reported reason for decrease in VBAC varied depending on whether a practitioner's hospital met ACOG guidelines. CONCLUSION: A marked decline in VBAC occurred after the change in ACOG vaginal birth after Cesarean policy. Multiple factors have contributed to this decline, including patients refusing VBAC after counseling and inability of institutions to meet ACOG guidelines.

Fetal atrial septal aneurysm. Prenatal diagnosis by ultrasonography.

OBJECTIVE: To assess prenatal diagnosis by ultrasonography in five cases of fetal atrial septal aneurysm. STUDY DESIGN: Five cases of fetal atrial septal aneurysm were diagnosed prenatally by ultrasound. Postpartum fetal cardiac echocardiography was performed in three of five infants from the first to the fourth day of life. The medical records of the five cases were reviewed and analyzed after delivery. RESULTS: Echocardiograms confirmed atrial septal aneurysm in two of the three neonates. One of the two infants was also found to have a patent foramen ovale, and the other infant had patent duct arteriosis in addition to a patent foramen ovale. Two had fetal cardiac arrythmias that resolved after birth. CONCLUSION: Atrial septal aneurysm in fetuses may be a natural transition in spontaneous closure of the associated patent foramen ovale or septal defect. The same phenomenon has been found in children and infants. Due to the uniqueness of the fetal circulation, atrial septal aneurysm may predispose to fetal arrythmias.

Prenatal diagnosis of fetal bladder and cloacal exstrophy by ultrasound. A report of three cases.

BACKGROUND: Bladder and cloacal exstrophy can be diagnosed with prenatal ultrasound. CASES: Three cases of bladder and cloacal exstrophy were diagnosed prenatally by ultrasound and confirmed at birth. The ultrasound findings were a soft tissue mass in the lower abdominal wall (which appeared larger and more heterogeneous in cloacal exstrophy than in bladder exstrophy), absent bladder, malformation of the external genitalia and normal kidneys along with normal amniotic fluid volume. CONCLUSION: Prenatal diagnosis of these defects will allow appropriate referrals prior to birth.

Thrombotic thrombocytopenic purpura as a cause of thrombocytopenia in pregnancy: literature review.

Thrombocytopenia complicating pregnancy occurs with four major nonmalignant conditions found in the reproductive age group: thrombotic thrombocytopenic purpura, hemolytic uremic syndrome, pregnancy-induced hypertension, and immune thrombocytopenic purpura. A case of thrombotic thrombocytopenic purpura occurring in a pregnant patient is presented, along with a review of the literature.

Hepatic vascular calcification: an early second trimester sonographic feature of idiopathic infantile arterial calcinosis.

Prenatal sonographic diagnosis of idiopathic infantile arterial calcinosis has been limited to the third trimester. We report a monozygotic twin gestation for which an 18-week ultrasound detected the unique finding of hepatic vascular calcification as the earliest feature of the disorder. In contrast to previous reports, second-trimester ultrasound may permit timely diagnosis of idiopathic infantile arterial calcinosis.

Bilateral inferior petrosal sinus corticotropin sampling with corticotropin-releasing hormone stimulation in a pregnant patient with Cushing's syndrome.

A patient was diagnosed with Cushing's syndrome during her first pregnancy. Bilateral simultaneous inferior petrosal sinus corticotropin sampling with corticotropin-releasing hormone stimulation was performed before transphenoidal pituitary adenomectomy, with successful localization of the pituitary adenoma. Her Cushing's syndrome was controlled postoperatively with resolution of hypertension. This case report demonstrates that the procedure of bilateral simultaneous inferior petrosal venous corticotropin sampling can be safely performed during pregnancy.

Measurement of fetal nasal width by ultrasonography.

OBJECTIVE: This study was designed to determine the range of normal fetal nasal width by ultrasonography, which may be beneficial for detection of trisomy 21 and other chromosomal abnormalities. We hypothesize that a wide, saddle-shaped nose, which is one of the clinical neonatal anatomic features of trisomy 21, can be diagnosed prenatally. STUDY DESIGN: Fetal nasal width diameter was measured on 782 normal white fetuses by ultrasonography. Gestational ages ranged from 13.8 to 40.4 weeks. Mean and SD of fetal width diameter was calculated weekly by gestational age to establish normal values. RESULTS: The fetal nasal width increased as a function of gestational age, showing a polynomial curve during pregnancy (r = 0.912, p = 0.002). With use of mean +/- 1 SD as a cutoff value, the results showed a sensitivity of 80% with a specificity of 67% and a positive predictive value of 2.2% with a negative predictive value of 99.7% for the diagnosis of trisomy 21. CONCLUSION: The fetal nasal width diameter may be used as a biometric measurement and may be useful to identify trisomy 21 or other chromosomal abnormalities in conjunction with other already defined parameters used in a genetic ultrasonographic screen.

Highly abnormal maternal inhibin and beta-human chorionic gonadotropin levels along with severe HELLP (hemolysis, elevated liver enzymes, and low platelet count) syndrome at 17 weeks' gestation with triploidy.

A 17-week pregnancy complicated by severe hypertension is reported. The fetus had multiple anomalies and was found to have triploidy. Assay of maternal serum markers for trisomy 21 revealed elevated levels of inhibin (137.51 multiples of the median) and human chorionic gonadotropin (41.51 multiples of the median).

Prenatal diagnosis of nonmosaic trisomy 9 and related ultrasound findings at 11.7 weeks.

Trisomy 9 is a relatively rare chromosomal abnormality. There have been no reports of first trimester ultrasound findings associated with mosaic or nonmosaic trisomy 9 in the literature. A case of nonmosaic trisomy 9 diagnosed prenatally with ultrasound findings at 11.7 weeks gestation is presented along with associated abnormal ultrasound findings.

Estimation of fetal weight: mean value from multiple formulas.

Mean fetal weight value from multiple formulas was compared to fetal weight from single formulas. Data were collected on 975 fetuses who had estimation of fetal weight by ultrasonography within 1 week before birth. Improvement in estimation of fetal weight occurred using either the mean value of multiple formulas or the Hadlock BPD/FL/AC, in comparison to fetal volume, BPD/AC, or FL/AC. BPD/FL/AC appeared to provide the best estimate of true weight in terms of overall accuracy and in terms of not showing a trend in either overestimating or underestimating true weight.

Intrauterine fetal growth in concordant twin gestations.

We longitudinally assessed intrauterine ultrasonic growth parameters (biparietal diameter, head circumference, abdominal circumference, and femur length) in 60 pairs of concordant twins. Head circumference to abdominal circumference and femur length to abdominal circumference ratios were calculated. Estimated fetal weight curves were created with the formula of Shepard et al., incorporating biparietal diameter and abdominal circumference, as well as that of Hadlock et al., incorporating femur length and abdominal circumference. Biparietal diameter was obtained in only 79% of fetuses, whereas femur length and abdominal circumference were obtained in 96% and 99% of fetuses, respectively. The intrauterine growth of abdominal circumference appears to be linear between 18 and 40 weeks, fitting the simple equation abdominal circumference = -4.5 + 0.97 gestational age (gestational age in weeks). The mean femur length to abdominal circumference ratio is 22.4 +/- 1.5 and appears to be gestational age independent between 20 and 40 weeks. The head circumference to abdominal circumference ratio decreases as gestational age advances in a linear fashion. Estimated fetal weight curves by the formulas of both Shepard et al. and Hadlock et al. fit second-order polynomial equations. Neither formula appears to be superior in estimating fetal weight in twin gestations, although that of Hadlock et al. can be used more frequently since biparietal diameter cannot always be obtained in both twins.

Cord blood gases and abnormal fetal biophysical assessment in preterm premature rupture of the membranes.

The relationship between cord blood gases and infection outcome was determined in 53 consecutive patients with preterm premature rupture of the membranes who were delivered because of abnormal fetal biophysical assessment. Measures of infection outcome included the presence of clinical amnionitis, possible neonatal sepsis, and neonatal sepsis. Fetal acidosis at birth, as defined by cord arterial pH less than 7.20, was found in six fetuses; five of these developed neonatal sepsis and the other was born to a mother who had intrapartum clinical amnionitis. The mean cord blood pH (artery and vein) of fetuses with neonatal sepsis was significantly less than in fetuses with possible neonatal sepsis or no sepsis; however, two thirds (10 of 15) of the neonates with sepsis had normal acid-base status at birth. These data suggest that the fetal biophysical assessment becomes abnormal before the development of fetal acidosis. The possible mechanisms by which fetal infection diminishes fetal biophysical activities prior to the development of acidosis are discussed.

Normal midtrimester (17-20 weeks) genetic sonogram decreases amniocentesis rate in a high-risk population.

OBJECTIVE: To evaluate a screening protocol using advanced maternal age, triple-marker screening, and genetic sonography. METHODS: We compared adverse chromosomal outcomes of pregnancy in 1556 women referred for increased risk of aneuploidy because of either advanced maternal age or triple-marker test results. Patients were counseled about the results of the triple-marker test and subsequent sonography, which led to a patient decision of whether to pursue amniocentesis. Fetal measurements and structural abnormalities were compared with chromosomal findings. When patients elected amniocentesis, karyotypes were obtained. RESULTS: Genetic sonography reduced the rate of amniocentesis by 61% overall and by 40% when compared with an alpha-fetoprotein profile alone. The sensitivity of sonography combined with the triple-marker screen for the detection of trisomy 21 was 87% compared with 91% for the triple-marker screen alone. CONCLUSIONS: This study confirmed that sonographic findings in a targeted population, in combination with other risk markers (advanced maternal age and triple-marker screening), can be used to assess the risk of aneuploidy. Biometry provides additional information for assessing the risk of aneuploidy. Combining advanced maternal age, serum triple-marker screening, and sonographic screening may provide better risk prediction for use in clinical counseling.

Comparison of six different ultrasonographic methods for predicting lethal fetal pulmonary hypoplasia.

Nomograms of six different ultrasonographic fetal parameters were established by studying uncomplicated, singleton pregnancies, with well-established dates, between 16 and 40 weeks of gestation. The studied parameters could reflect fetal lung mass and included the following: chest circumference (CC), chest area (CA), chest area minus heart area (CA - HA), chest circumference/abdominal circumference ratio (CC X 100/AC), chest area/heart area ratio (CA/HA), and chest area minus heart area divided by chest area ratio [(CA - HA) X 100/CA]. The effect of ruptured membranes on these six ultrasonographic parameters was assessed by studying patients who had premature rupture of the membranes of less than 1 week's duration. It was found that premature rupture of the membranes is associated with increased frequency of CC, CA, and CA - HA measurements at or below the 5th percentile. However, in patients with premature rupture of the membranes all measurements were within the normal range for the three ratios. The efficacy of each of the six parameters was determined by studying 13 fetuses at high risk for development of lethal pulmonary hypoplasia. The (CA - HA) X 100/CA parameter had the best diagnostic accuracy (sensitivity 85%, specificity 85%, positive predictive value 83%, and negative predictive value 85%).