Maternal pseudo primary hyperaldosteronism in twin-to-twin transfusion syndrome.

OBJECTIVE: To monitor changes in the maternal renin-angiotensin-aldosterone system following laser therapy and amnioreduction in severe twin-to-twin transfusion syndrome (TTTS). DESIGN: Observational prospective study. SETTING: Single university hospital in Poissy, France. POPULATION: Sixty cases of TTTS at 16-26 weeks of gestation. METHOD: Maternal blood sampling before, 6 and 24 hours following the procedure. MAIN OUTCOME MEASURES: Plasma levels of aldosterone, renin, angiotensin II (AII), atrial natriuretic peptide (ANP), vasopressin, sodium, potassium and plasma proteins together with full blood count were measured before, 6 and 24 hours following the procedure. RESULTS: TTTS is associated with maternal hyperaldosteronism dissociated from renin-angiotensin changes. Correcting TTTS by placental surgery and amnioreduction triggers incomplete correction of hyperaldosteronism, as early as 6 hours following the procedure, without changes in AII but an increase in the levels of ANP in plasma. Electrolyte concentrations remained stable despite haemodilution, while vasoactive hormone levels such as that of vasopressin remained unchanged. CONCLUSION: Mechanisms involved in marked fluid retention in TTTS are rapidly corrected by laser therapy followed by amnioreduction while maintaining electrolyte homeostasis.

Familial diseases revealed by a fetal anomaly.

OBJECTIVES: The recognition of a fetal anomaly can lead to the same diagnosis being made in one of the asymptomatic parents unaware of the problem. We analyzed cases in which the discovery of a fetal anomaly led to the discovery of a genetic familial disorder. METHODS: Families in which the recognition of a fetal anomaly led to the same diagnosis being made in one of the asymptomatic parents were included. RESULTS: Twenty couples were included in the study. The fetal anomalies were cleft lip and palate (4), cardiac anomalies (2), cerebral anomalies (1), bilateral club feet with polyhydramnios, akinesia or camptodactily (5), nuchal anomalies (2), micromelia (3), polydactyly (2), and limited elbow extension (1). Genetic counselling helped establish nine maternal diseases as follows: Steinert disease (3), spinal muscular atrophy (1), antecubital pterygium (1), DiGeorge (1), Wardenburg type II (1), Charge (1) and Greig syndromes (1). Eleven paternal diseases were discovered, which were Noonan-like syndrome (1), paternal cervical anomalies (1), Goldenhar syndrome (1), dominant autosomal arthrogryposis (1), osteogenesis imperfecta (3), tuberous sclerosis (1), dominant transposition of great vessels (1), Weyers acrofacial dysostosis (1), and autosomal dominant holoprosencephaly (1). Twelve couples continued with pregnancy and eight opted for termination of pregnancy. CONCLUSION: The fetus is central in giving the first insight into a familial disorder. It can reveal familial diseases undiscovered in the parent and help understand the mode of transmission of an anomaly, mainly the autosomal dominant diseases with variable expressions.

Intrauterine fetal demise following laser treatment in twin-to-twin transfusion syndrome.

OBJECTIVE: To evaluate the incidence, risk factors and consequences of intrauterine fetal demise (IUFD) of at least one twin in twin-to-twin transfusion syndrome (TTTS) treated by laser. DESIGN: Retrospective analysis. SETTING: Experience of a single centre between 1999 and 2004. POPULATION: A subgroup of 45 cases with fetal demise of one or both twins from a series of 120 cases of TTTS treated by laser. METHODS: All cases were entered prospectively into a dedicated database and the results were analysed retrospectively. MAIN OUTCOME MEASURES: Fetal demise prognostic factors, survival, fetal anaemia, brain lesions, neonatal death and intact survival. RESULTS: IUFD of one twin occurred in 40 of 120 cases (19 donors and 21 recipients). IUFD of both twins occurred in another five cases. From these 40 cases, miscarriage occurred in two and pregnancy termination was requested in another two cases because of antenatal brain lesions. Two neonates died and two presented severe morbidity, survivors were therefore neurologically normal at 6-44 months of life in 89% (32/36) of the cases. Univariate analysis showed that preoperative abnormal umbilical artery Doppler in the donor before laser treatment and in the recipient following laser treatment was associated with their demise. Incomplete coagulation was suspected in cases where anaemia or cerebral lesions developed following the death of the first twin (10). CONCLUSIONS: IUFD of one or both twins occurred in 45 of 120 (38%) cases of severe TTTS treated by laser. In these, separation of the placental circulations was incomplete in at least 22% (10/45) of the cases. Umbilical artery Doppler abnormalities before laser were found to be risk factors for the donors' demise following the procedure.

Inter- and intraobserver variability in sonographic measurement of the lower uterine segment after a previous Cesarean section.

OBJECTIVE: To evaluate the reproducibility of sonographic measurement of the lower uterine segment in pregnant women at term. METHODS: Two independent observers performed transabdominal sonography on 129 women between 36 and 38 weeks of gestation who had had a previous Cesarean section. Sonography was performed when the patients had a full and a half-full bladder; in 100 patients, the measurements were also performed transvaginally, with the patients having an empty bladder. Agreement was quantified by the intraclass correlation coefficient and, using a cut-off of 3.5 mm, by the kappa coefficient. RESULTS: The intraobserver agreement was generally high (intraclass correlation coefficient > 0.90). The interobserver agreement was higher on transvaginal (intraclass correlation coefficient, 0.94) compared with transabdominal (0.70 and 0.84, with full and half-full bladder, respectively) ultrasound. The kappa coefficient was 0.75 transvaginally, compared with 0.34 and 0.54 using the transabdominal approach, with full and half-full bladder, respectively. CONCLUSION: The agreement between two observers for sonographic transvaginal measurement of the lower uterine segment can be considered good, compared with poor to moderate agreement using the transabdominal approach.

Management of fetofetal transfusion syndrome.

Feto-fetal transfusion syndrome contributes heavily to high rates of perinatal mortality and morbidity in monochorionic multiple pregnancies. Its prenatal management has been controversial for at least 25 years. We review the recent literature in order to present the basis for a pragmatic reappraisal of the management of this condition. Laser surgery of the chorionic plate inter-twin anastomoses is the best first-line treatment when the syndrome develops before 26 weeks' gestation. Survival (including quality of survival) and gestational age at delivery are improved when compared to serial amnioreduction. Second-line treatment options include repeat-laser, intra-uterine blood transfusion, serial amnioreduction, selective feticide using bipolar cord coagulation or elective delivery, depending upon gestational age and the severity of the disease and its complications. We have found that fetoscopic placental surgery has proven itself over simplicity of amnioreduction. There is no evidence that treatment should be customized according to the stage of the disease at diagnosis. Early recognition of the syndrome through fortnightly serial ultrasound follow-up of all monochorionic pregnancies should ensure timely referral and make up for geographical constraints. Laser surgery should now be available in fetal medicine units that are managing at least 20 cases per year.

Correlation between ultrasound and anatomical findings in fetuses with lower urinary tract obstruction in the first half of pregnancy.

OBJECTIVE: The prognosis of fetal lower urinary tract obstruction (LUTO) depends upon renal function and also upon the underlying etiology. Precise identification of the latter remains a challenge antenatally. Our objective was to examine the underlying pathology in male fetuses with sonographic evidence of severe and isolated LUTO. METHODS: Detailed postmortem examination was carried out after termination of pregnancy in 24 male fetuses presenting before 25 weeks of gestation with ultrasound evidence of isolated severe LUTO. RESULTS: All fetuses had megacystis and hyperechogenic kidneys. There was anhydramnios/oligohydramnios and pelvicalyceal dilatation in 20 and 15 cases, respectively. Posterior urethral valves (PUV) were suspected antenatally in 20 cases and urethral atresia was not suspected antenatally. However, postmortem examination of the urethra demonstrated atresia in six cases, severe stenosis in eight cases, PUV in nine cases and an apparently normal urethra in one case. Renal dysplasia was found in all cases but one. Urethral atresia was the most common urethral anomaly at 12-17 weeks. Hydronephrosis was more frequent in cases with PUV (8/9) and urethral stenosis (6/8) than with urethral atresia (0/6). In LUTO presenting in the first and second trimester, hyperechogenic kidneys were predictive of renal dysplasia in 95% of cases. The association of a sagittal diameter of the bladder of at least 40 mm with hydronephrosis before 28 weeks was predictive of PUV with a positive (PPV) and negative (NPV) predictive value of 44.4% and 66.6%, respectively. Absence of hydronephrosis and a sagittal diameter of the bladder of less than 40 mm were predictive of urethral atresia or stenosis with a PPV and NPV of 100% and 47.6%, respectively. The absence of hydronephrosis was predictive of urethral atresia with a PPV and NPV of 66.6% and 100%, respectively. CONCLUSION: LUTO in a male fetus presenting with megacystis in the first or second trimester of pregnancy is as likely to reflect urethral atresia or stenosis as it is PUV. The size of the bladder and the presence of hydronephrosis should be considered in order to improve prenatal diagnosis and counseling.

Dandy-Walker syndrome and corpus callosum agenesis in 5p deletion.

5p deletion syndrome commonly known as cri du chat is well described in affected neonates with catlike cry and hypotonia. Karyotyping will usually show a deletion of the short arm of one chromosome 5 with variable breakpoints. Only a few cases have been reported prenatally, and the fetal form of the syndrome has not been clearly individualised. We report a new case of 5p deletion syndrome diagnosed prenatally in association with Dandy-Walker syndrome and agenesis of the corpus callosum. Other brain anomalies have been reported previously, but this unusual association suggests the use of a specific probe in the investigation of these malformations.

Cervical length as a prognostic factor for preterm delivery in twin-to-twin transfusion syndrome treated by fetoscopic laser coagulation of chorionic plate anastomoses.

OBJECTIVE: To evaluate the risk of spontaneous preterm delivery in relation to cervical length in severe cases of twin-to-twin transfusion syndrome (TTTS) diagnosed before 26 weeks of gestation and treated by laser coagulation of the intertwin placental anastomoses. METHODS: This was an observational study of cases of severe TTTS diagnosed before 26 weeks of gestation and treated by fetoscopic laser coagulation between January 2002 and December 2003 in three centers. Laser was the first-line treatment in all cases. Elective preterm deliveries before 34 weeks' for maternal or fetal indications, including intrauterine death of both fetuses, were excluded. Transvaginal sonographic measurement of cervical length prior to laser treatment and other risk factors of preterm delivery were evaluated by univariate and logistic regression analysis. RESULTS: Among the 137 women included, the mean cervical length was 32 and 38 mm in women delivering before and at or after 34 weeks, respectively (P < 0.001). For a cervical length of < 30 mm, the risk of delivery before 34 weeks was 74%. Severity of the disease, deepest vertical pool of amniotic fluid and amniotic fluid volume drained after the procedure were not associated with preterm delivery. Logistic regression analysis identified three independent factors to predict preterm delivery: short cervical length (increased risk), parity (increased risk) and intrauterine death of one twin (decreased risk). CONCLUSION: In TTTS treated by laser, without indications for elective preterm birth, cervical length before treatment is significantly associated with gestational age at delivery, and this is independent of parity, intrauterine death of one fetus and other risk factors.