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The diagnosis of esophageal atresia may be suspected on prenatal ultrasonography in fetuses with absent or small stomach, upper esophageal dilatation and unexplained polyhydramnios. However, the diagnostic value of these findings is relatively poor. Two cases are reported where MRI appeared to be accurate for establishing the diagnosis of this congenital anomaly.
We report a case of acute renal failure due to bilateral ureteral obstruction that rapidly resolved after delivery. Acute renal failure secondary to bilateral ureteral obstruction is rare; to our knowledge, only 18 cases have been reported in the English literature. Review of these cases reveals that twin pregnancies, polyhydramnios, and obstruction of the solitary kidney seem to increase the risk of obstructive renal failure. Measures including induced delivery, amniocentesis, and insertion of ureteral stents or nephrostomy tubes undertaken to relieve the ureteral obstruction usually lead to rapid improvement in urine flow and renal function. Acute renal failure secondary to bilateral ureteral obstruction is a rare but reversible complication of pregnancy.
The outcome of pregnancy in patients with end-stage renal failure has long been considered to be extremely poor, and the literature concerning pregnancy while on dialysis is rather scarce. We reviewed the records of five pregnancies in dialysis patients and performed a national survey on this topic. The dialysis technique and dialysis dose, the effects of erythropoietin (EPO), and the evolution of blood pressure levels in our patients are presented. The dose of EPO had to be increased to maintain the hemoglobin level at 10 to 11 g/dL. There was no case of EPO-related hypertension and no need for transfusion. The obstetric data of the national survey, including our own patients, were analyzed. The incidence of pregnancy going beyond the first trimester was 0.3 per 100 patient-years (15 cases in 1,472 females of childbearing age treated, for a total of 4,545 patient-years). In all but one patient initiating pregnancy while already on dialysis, the frequency and dose of dialysis were increased (to a weekly Kt/V of six to eight in our personal cases). The outcome was successful in 50% of pregnancies occurring in hemodialyzed patients and in 80% of patients who started dialysis after initiation of pregnancy. Polyhydramnios was found in eight of 13 cases and growth retardation in two of nine cases. The incidence of low birth weight and prematurity was 100%, and cesarean section was performed in 66% of successful pregnancies. In successful pregnancies, we found a correlation between birth weight and dose of dialysis. Our findings confirm the remarkable improvement in the prognosis of pregnancy in dialysis patients in recent years.
OBJECTIVE: Monochorionic twins with circulatory sharing have an incompletely understood response to acute hemodynamic events. We relate placental vascular anatomy with, first, the response to (a) acute fetal demise and (b) laser interrupted placental anastomoses and, second, the efficacy of current and possibly future therapeutic interventions in twin-twin transfusion syndrome. DESIGN: Hemodynamic response to acute fetal demise and laser interrupted anastomoses is analysed using the model previously developed for monochorionic twins. Efficacy of therapeutic interventions in twin-twin transfusion syndrome is analysed by combining the estimated incidence of placental anastomotic patterns with three previously proposed pathophysiologic mechanisms. RESULTS: Fetal demise may cause sequelae for the co-twin in all anastomotic patterns except unidirectional arteriovenous and single venovenous anastomoses which are predicted to be hemodynamically harmless. In twin-twin transfusion syndrome, laser interruption of all anastomoses mitigates further transfusion. This is of benefit for the twins in equally but not in unequally shared placentas. Analysis predicts that approximately 75% fetal survival could be achieved interrupting only arteriovenous anastomoses. Amniocentesis may only prolong pregnancies that lack progressively increasing discordance, assuming that placental anastomoses remain patent following polyhydramnios. This proposed mechanism of action predicts current therapeutic efficacy accurately and could explain the significantly higher reported serious morbidity compared with laser (15/81 = 19+/-5% versus 4/146=3%, P=0.00004). However, if therapeutic interventions could match the syndrome's individual placental anatomy, the analysis suggests approximately 10-15% laser related mortality (premature rupture of membranes) and <3% severe morbidity could possibly become achievable goals. CONCLUSION: Our predictions allow clinical testing. This information may contribute to an improved management of monochorionic twins.
Fetal biometry, amniotic fluid volume distribution and perinatal outcome were determined in a retrospective, cross-sectional matched-control study design, including 20 monochorionic (MC) twin pregnancies and 20 dichorionic (DC) twin pregnancies (historic controls). Intertwin differences for fetal abdominal circumference were larger in the MC subset than in the DC subset. Fetofetal transfusion syndrome, based upon a combination of oligohydramnios in one sac and polyhydramnios in the other sac, existed in 40% (8 of 20) of the MC twin pregnancies, but in none of the DC twin pregnancies. Mean gestational age at delivery was significantly shorter in the MC subset (30.9 weeks) than in the DC subset (34.3 weeks). The perinatal death rate was significantly higher in MC twin pregnancies (50%) than in DC twin pregnancies (15%). No differences were established for intertwin weight estimates by ultrasound and birth weight between both subsets. The poor perinatal outcome in monochorionicity is mainly a result of the degree of premature delivery.
The developing fetal upper aerodigestive system provides the structural support for respiratory and ingestive functions necessary to sustain life at birth. This study investigated prenatal development of upper aerodigestive anatomy and the association of emerging functions as predictors of postnatal feeding skills. Biometric measures of oral, lingual, pharyngeal and laryngeal structures were obtained in fetuses 15-38 weeks gestational age using a four-plane sonographic technique. Accompanying ingestive behaviors were tallied across development. The data from 62 healthy controls were compared to seven cases at risk for postnatal feeding and swallowing dysfunction (Type II Arnold Chiari Malformation, trisomy 18, polyhydramnios, intrauterine growth restriction, Brachmann-de Lange Syndrome). Significant (p<0.001) linear regressions occurred in pharyngeal and lingual growth across gestation while ingestive behavior such as suckling emerged in a sequence of basic to complex movement patterns. Jaw and lip movements progressed from simple mouth opening to repetitive open-close movements important for postnatal suckling. Lingual movements increased in complexity from simple forward thrusting and cupping to anterior-posterior motions necessary for successful suckling at term. Laryngeal movements varied from shallow flutter-like movements along the lumen to more complex and complete adduction-abduction patterns. Fetal swallowing primarily occurred in the presence of concomitant oral-facial stimulatory activity. Significant variations (p<0.01) in the form and function of the ingestive system occurred in comparisons of gestational age-matched controls to at-risk cases. We postulate that prenatal developmental indices of emerging aerodigestive skills may guide postnatal decisions for feeding readiness and, ultimately, advance the care of the premature, medically fragile neonate.
Ultrasonography has expanded the capabilities of perinatologists to examine,test, and treat the fetus. Amniocentesis and CVS are safe and widely available procedures, which can be used to diagnose a multitude of abnormalities through karyotype analysis and molecular studies. CVS allows earlier diagnosis, but both procedures can provide highly accurate results in the first half of pregnancy. Cordocentesis has fewer indications, but allows direct laboratory testing of fetal blood. Fetocentesis and fetal biopsy are reserved for limited indications, but can play a crucial role in the diagnosis of some conditions, which cannot be assessed less invasively. Fetal transfusion is an important tool in the treatment of isoimmunization, some other forms of fetal anemia, and alloimmune thrombocytopenia. Amnioreduction is a commonly used procedure for the treatment of polyhydramnios and TTTS. Multifetal reduction and selective termination offer previously unavailable options to patients carrying multiple gestations. Fetal shunts can reduce perinatal morbidity and mortality in cases of bladder outlet obstruction and hydrothorax. The limited experience with cord ligation procedures and balloon valvuloplasty suggests these relatively new procedures may serve a greater role in the future as techniques are improved. By providing guidance for all of these procedures, real-time ultrasonography has revolutionized prenatal diagnosis and therapy; it will continue to be a crucial component in evaluating and treating complicated pregnancies.
Primary prevention of PPH is advocated at all levels of obstetric care. This implies active management of the third stage of labour also at the first and most peripheral levels of obstetric care. Active management includes the use of an oxytocic, early cord clamping and active delivery of the placenta. The oxytocic drug of choice at this moment is oxytocin 5 IU given intramuscularly. Women with high-risk factors for PPH (polyhydramnios, previous complications in third stage, APH or multiple pregnancies) should be delivered in hospital. Timely antepartum referral is necessary. In these women, prevention and anticipatory management includes the availability of intravenous treatment, as well as active management with an oxytocic. Evidence for the effectiveness of active management of the third stage of labour in women at low risk of PPH is not yet available. Whether women delivering at home with easy accessibility to hospital, or those at low risk delivering in hospital, should be actively managed remains controversial, and such an approach is not supported by us until a clinical trial in this particular group of women has shown the effectiveness of the active management.
Since the metabolic changes in normal pregnancy are diabetogenic, pregnancy imposes a severe stress on the metabolic milieu of diabetic patients. Moreover, many patients with long-standing diabetes have vascular complications, including retinopathy, renal insufficiency, nephrotic syndrome and hypertension, that represent separate risk factors for optimal fetal development. Recent experience has suggested that maternal hyperglycaemia, and associated fetal hyperinsulinaemia, may represent an important factor in the development of fetal complications. During the past two to three decades the incidence of perinatal deaths has been reduced in all cases of diabetics to a level that approaches the rate in healthy gravidas when severe congenital anomalies are excluded. Fetal and neonatal morbidity have also been reduced, although rates of congenital anomalies, polyhydramnios and respiratory distress syndrome remain high. In patients with significant vascular complications, especially nephropathy and retinopathy, there is no evidence that pregnancy alters the natural course of these complications. Although the morbidity associated with oedema formation and hypertension is elevated, with meticulous management of patients with diabetic nephropathy, especially in the absence of severe renal insufficiency and/or severe hypertension, pregnancy performance and outcome can be similar to other insulin-dependent diabetics.
Monochorionic (MC) placentation occurs in two-thirds of monozygous twins and approximately 0.3% of all spontaneous conceptions. Vascular anastomoses within the placenta allow intertwin transfusion to occur, which is in most cases a normal event. However, imbalance in this flow may lead to the clinical sequelae observed, with acute, chronic or reverse intertwin transfusion. Acute transfusion describes the events following the death of one of an MC twin pair in utero, with an approximately 1 in 4 chance of demise or neurological damage in the co-twin. Chronic intertwin transfusion, otherwise termed feto-fetal transfusion syndrome, arises following the gradual flux of blood from one twin (the donor) to its sibling fetus (the recipient). The ensuing polyhydramnios places the pregnancy at risk of preterm amniorrhexis and/or labour, notwithstanding the specific sequelae seen in these fetuses following chronic in utero insult. Reverse transfusion describes the most bizarre form of intertwin transfusion: acardiac twinning. Retrograde perfusion of one of the twins with deoxygenated blood leads to the formation of a non-viable acardiac parasite and a 'pump twin' struggling to maintain the cardiac output required to perfuse both twins.
OBJECTIVE: We evaluated the feasibility of a new instrument for continuous fetal pulse oximetry during labor. The measuring sensor can be placed on the fetal back before or after rupture of membranes. METHODS: One hundred adult women who had completed 32 weeks of gestation and had an anticipated duration of labor greater than 30 minutes were included in the study. Patients with premature rupture of membranes for 24 hours or more, low placental localization, placenta previa or abruption, vaginal bleeding, acute infection, polyhydramnios, oligohydramnios, or uterine or congenital abnormalities were excluded. RESULTS: All sensors were placed successfully. The mean continuous recording time was 276 minutes. Peripheral oxygen saturation as measured by pulse oximeter values were obtained during a median of 64.05% of the recording time. No chorioamnionitis or endometritis was noted. CONCLUSION: The new sensor instrumentation was safe for mother and fetus and was well accepted by parents and physicians.
Sacrococcygeal teratoma is a rare fetal neoplasm with an incidence of 1 in 40,000 births. Antenatal diagnosis is usually made after 22 weeks of gestation. Fetuses with this malformation are at risk of significant perinatal morbidity and mortality. Malignant components, coexisting with life-threatening anomalies, and chromosomal abnormalities are rare. Postulated causes of perinatal death include hydrops, dystocia, tumor rupture, preterm labor secondary to polyhydramnios, and anemia due either to hemorrhage or hemolysis within the tumor. Herein, we present a case of fetal sacrococcygeal teratoma diagnosed as early as 17 weeks of gestation.
The twin reversed arterial perfusion (TRAP) sequence is a very rare complication of multiple gestations and is associated with a high mortality rate, reaching more than 50% in pump twins. The four common complications are preterm labor, polyhydramnios, fetal congestive heart failure, and fetal death of the pump twin in utero. Prenatal diagnosis during early pregnancy is possible using detailed ultrasonographic examination. Therapies, including conservative treatment and invasive procedures, are directed toward achieving optimal maintenance of pump twins based on clinical presentation. Risk factors for pump twin mortality include a high twin-to-twin weight ratio, acardiacus anceps, low umbilical artery pulsatility index, and a rapid growth rate in the acardiac twin. Herein, we present a case of TRAP sequence in a patient who underwent conservative treatment and had a poor neurologic outcome during long-term follow-up. Although the experience is still limited, early diagnosis of TRAP sequence and more aggressive treatment, instead of an expectant approach, might be a better option.
OBJECTIVE: To identify key demographic, lifestyle, and medical indicators for preterm births in women aged 20 to 34. METHODS: A population-based, case-control study consisting of 987 women aged 20 to 34, who delivered a liveborn singleton infant at <37 weeks' gestation in Alberta between May 1999 and August 2000. Controls delivered liveborn infant(s) at > or =37 weeks' gestation. Information was obtained from computer-assisted telephone interviews, and the provincial Physician Notice of Stillbirth/Birth database. Analysis included bivariate and logistic regression techniques. RESULTS: Logistic regression modelling indicated that significant risk factors for preterm delivery included poor past pregnancy outcome (odds ratio [OR] 6.4), poor emotional health (OR 1.8), more than 3 years or less than 1 year between pregnancies (OR 1.4 and 1.9, respectively), polyhydramnios and oligohydramnios (OR 4.1), bleeding at greater than 20 weeks' gestation (OR 10.4), malpresentation (OR 2.9), gestational hyper- tension (OR 2.2), and gestational hypertension with proteinuria (OR 4.4). Women who had fewer than 10 prenatal visits, regardless of attending prenatal classes, were at highest risk of preterm delivery (OR 6.7). CONCLUSIONS: In this population of women aged 20 to 34 years, few prenatal visits, poor emotional health prior to pregnancy, and conditions of the current pregnancy were strongly associated with preterm singleton birth.
OBJECTIVE: To assess the risk factors for preterm birth in twin pregnancies, particularly monochorionicity. METHODS: A cohort study of 767 sets of twins, each twin weighing more than 500 g, born between January 1, 1992, and December 31, 2001, at St. Joseph's Health Care in London, Ontario. Statistical analysis was performed using forward stepwise logistic regression models, with gestational age at birth less than 28 or 32 weeks as the outcome. RESULTS: Polyhydramnios and chorioamnionitis were significant risk factors for preterm birth prior to 28 or 32 weeks' gestation. Monochorionicity was a risk factor for preterm birth prior to 32 weeks' gestation. Past term birth and maternal age over 30 years were associated with reduced risk for preterm birth. CONCLUSION: Monochorionic placentation is a significant risk factor for preterm twin birth.
PURPOSE: To demonstrate the ocular histopathologic findings in Fryns syndrome, a multiple congenital anomaly syndrome, with characteristic features including Dandy-Walker malformation, cleft palate, diaphragmatic hernia, lung hypoplasia, distal limb anomalies and polyhydramnios. The prevalence is about 0.7 per 10,000 births. Reported ocular features include microphthalmus, "cloudy cornea", irregularities of Bowman's layer, thickened posterior lens capsule and retinal dysplasia. METHODS: Case report. The ocular histopathologic and ultrastructural findings in a male fetus with Fryns syndrome who died immediately after his birth at 26th week of gestation are shown. RESULTS: An abnormal Descemet's membrane was found in addition to "cloudy corneae". Electron microscopy demonstrated absence of the banded collagen fibrils in Descemet's membrane, indicating corneal endothelial dysfunction. Otherwise, the eye was morphologically normal for its age; none of the other reported ocular features of Fryns syndrome were found. CONCLUSION: Corneal endothelial dysfunction might cause abnormal composition of anterior Descemet's membrane and could contribute to the "cloudy cornea" known to occur in Fryns syndrome.
The gene IGF2, which encodes a fetal insulin-like growth factor, is imprinted, so only one of two parental copies of the gene is expressed. The altered expression of IGF2 has been implicated in Beckwith-Wiedemann syndrome, a human fetal overgrowth syndrome, which is characterized by overgrowth of several organs and an increased risk of developing childhood tumours. We have introduced Igf2 transgenes into the mouse genome by using embryonic stem cells, which leads to transactivation of the endogenous Igf2 gene. The consequent overexpression of Igf2 results in most of the symptoms of Beckwith-Wiedemann syndrome, including prenatal overgrowth, polyhydramnios, fetal and neonatal lethality, disproportionate organ overgrowth including tongue enlargement, and skeletal abnormalities. These phenotypes establish Igf2 overexpression as a key determinant of Beckwith-Wiedemann syndrome.
OBJECTIVE: The purpose of this study was to evaluate the prognostic value of sonographic and clinical parameters to develop a staging classification of twin-twin transfusion syndrome (TTTS). STUDY DESIGN: Severe TTTS was defined as the presence of polyhydramnios (maximum vertical pocket of > or = 8 cm) and oligohydramnios (maximum vertical pocket of < or = 2 cm). Nonvisualization of the bladder in the donor twin (-BDT) and absence of presence of hydrops was also noted. The middle cerebral artery, umbilical artery, ductus venosus, and umbilical vein in both fetuses were assessed with pulsed Doppler. Critically abnormal Doppler studies (CADs) were defined as absent/reverse end-diastolic velocity in the umbilical artery, reverse flow in the ductus venosus, or pulsatile flow in the umbilical vein. TTTS was staged as follows: stage I, BDT still visible; stage II, BDT no longer visible, no CADs; stage III, CADs; stage IV, hydrops; stage V, demise of one or both twins. Laser photocoagulation of communicating vessels (LPCV) or umbilical cord ligation was performed depending on the severity of the condition. The study was approved by the Institutional Review Board of St. Joseph's Hospital in Tampa and by the Fetal Therapy Board at Hutzel Hospital, Detroit, and all patients gave informed consent. RESULTS: A total of 80 of 108 referred patients met criteria for surgery, but only 65 were treated surgically: 48 with LPCV and 17 with umbilical cord ligation. Complete Doppler data were obtainable in 41 of 48 LPCV patients. Survival rates by stage for one or two fetuses were statistically different (chi-squared analysis = 12.9, df = 6, p = 0.044). Neither percent size discordance nor gestational age at diagnosis were predictive of outcome. CONCLUSION: Staging of TTTS using the proposed criteria has prognostic significance. This staging system may allow comparison of outcome data of TTTS with different treatment modalities.