Nearly half of all severe fetal anomalies can be detected by first-trimester screening in experts' hands.

Objective To evaluate the detection rate of severe fetal anomalies at the first-trimester screening (FTS) and, vice versa, to evaluate the follow-up of pathological results at FTS at the time of mid-trimester screening (MTS) and throughout pregnancy and delivery in a partially selected population of low-risk pregnancies. Methods We conducted a prospective study on the detection of severe fetal anomalies at routine FTS in 9891 pregnant women with 10,294 fetuses between 11 + 0 and 13 + 6 weeks of gestation. The findings of FTS were compared to the results of MTS and pregnancy and neonatal outcomes. Only cases with severe fetal anomalies were taken for statistical analysis in this study. Results There were 232 cases of fetal anomaly altogether. At the time of FTS, sonographic anomalies were diagnosed in 113 cases and further ultrasound controls arranged. In four cases, fetal anomaly was not confirmed by MTS; in the remaining 109 cases, the sonographic anomaly seen at FTS was confirmed at MTS and in the course of pregnancy with a resulting sensitivity for fetal malformation at FTS of 47.8%, a specificity of 99.96%, a positive predictive value of 96.5% and a negative predictive value of 98.8%. Conclusion FTS can detect almost half of all severe fetal anomalies at an early stage of pregnancy with positive predictive values of 90% and more. Sensitivities varied depending on the organ system and reached the highest figures for anomalies of the heart, the abdomen, the spine and the skeletal system.

A case of craniopagus parasiticus: an antenatal diagnosis by ultrasound screening at 16 weeks of gestation and a literature review of recently reported cases.

Al Yaqoubi HN, Fatema N, Al Fahdi BS. A case of craniopagus parasiticus: an antenatal diagnosis by ultrasound screening at 16 weeks of gestation and a literature review of recently reported cases. Turk J Pediatr 2019; 61: 941-945. Craniopagus parasiticus (CP) is a rare type of malformation of conjoined twins, with one degenerated or underdeveloped parasite twin united at the cranium with the other fully developed twin. Only a handful of cases have been documented in the literature to date. The incidence of this rare deformity is approximately 4 to 6 out of every 10,000,000 live births. We report on a case of CP, diagnosed at 16 weeks of gestation by ultrasound screening. To the best of our knowledge, the case that we present is the first CP case that was diagnosed at such an early gestational age. The formed fetus was found to harbour complex cardiac anomalies. In view of poor prognosis of survival after delivery and upon permission from the couple, the pregnancy was terminated at 17 weeks of gestation.

Heteropagus (parasitic) twins: a review.

Heteropagus, or "parasitic," twins are asymmetric conjoined twins in which the tissues of a severely defective twin (parasite) are dependent on the cardiovascular system of the other, largely intact twin (autosite) for survival. The estimated incidence of heteropagus twins is approximately 1 per 1 million live births. Isolated case reports comprise most of published work on this rare congenital anomaly. In the past, review articles have focused narrowly on one particular anatomical subtype of parasitic twin and/or on the anatomicopathology observed. Here, we present the epidemiology, proposed pathoembryogenic origins, anatomical abnormalities, management, and outcomes of the wide array of heteropagus twins described in the English language literature.

Prenatal diagnosis of thoracopagus fetus: a case report with brief review of literature.

Conjoined twins are uncommon and refer to monozygotic, monoamniotic and monochorionic twins with varying degree and sites of fusion between the twins. In this report, we illustrate a case of thoracopagus twins highlighting the prenatal sonographic and magnetic resonance imaging appearance. Emphasis is laid on the role of appropriate imaging strategy in prognostic assessment and postnatal surgical treatment planning of these cases.

Acardiac twin: an unusual case report.

Acardiac twinning is a rare anomaly .75% of cases occurring in monzygotic triplet pregnancies and the rest in monozygotic twins. We report an antenatally undiagnosed case of acardius amorphous. The condition results from abnormal placental vascular anastomoses termed as twin reversed arterial perfusion (TRAP) theory. Early sonographic prenatal diagnosis improves the survival of the normal twin called the pump twin.

Fetus amorphous acardious: report of a rare case and differential diagnosis from placental teratoma with review of the literature.

Fetus amorphous acardious is a rare fetal malformation, lacking a functional heart and bearing no resemblance to human embryos. The main differential diagnosis is with placental teratoma and is based on the degree of skeletal organization and umbilical cord formation. A 27-year old woman delivered a healthy newborn at 37 weeks' gestation. An amorphous mass, covered with healthy looking skin, was connected to the placenta with a short pendicle. X-ray examination of the mass revealed the presence of vertebral column associated with ribs and pelvic bones. Histopathologic examination demonstrated the presence of spinal tube inside the vertebral column. Microscopy of the pedicle was consistent with umbilical cord. Various other tissues were also discovered, such as adipose tissue, gastric and large.

Antenatal diagnosis of twin-reversed arterial perfusion sequence (acardiac amorphous) in a triplet pregnancy: case report.

Acardiac twinning is the most extreme form of twin-twin transfusion syndrome occurring in monzygotic twin pregnancies with monochorionic placentation. A case of acardiac amorphous foetus, occurring in association with spontaneously conceived triplet pregnancy, diagnosed on ultrasound in early second trimester is described and its antenatal management and brief review of literature discussed.

[Fetal thoracopagus. Echographic diagnosis at 26 weeks]. / Foetus thoracopages. Diagnostic échographique à 26 semaines.

The authors report on one case of thoracopagus discovered by echography carried out after 26 weeks of amenorrhoea. The pregnancy was terminated therapeutically by hysterotomy when common viscera were identified (heart and liver). Echographic diagnosis during the first part of pregnancy allows evacuation to be carried out by the vaginal approach. The authors summarize the criteria for echographic diagnosis and also the epidemiological and embryological data required for assessing the prognosis.

Holoacardius: antenatal diagnosis and pathogenetic evaluation: a case report.

A case of Holoacardius is reported by the authors. The literature is reviewed, and a pathogenetic sequence responsible for the syndrome is proposed on the basis of the pathologic data.

Teratoma of the placenta, a case report.

A mature solid teratoma of the placenta is presented. Like the other six, previously reported, cases it was located on the placental surface, between amnion and chorion. The nature of the tumor as well as its differential feature with fetus acardius amorphus are discussed.

[Thoracopagus fetus. Ultrasonic diagnosis at 16 weeks]. / Foetus thoracopages. Diagnostic échographique à 16 semaines.

This paper reports the ultrasound diagnosis at 16 weeks' gestation of thoracopagus conjoined twins. Ultrasound examination showed the two fetuses conjoined at the sternum, with a single heart and a single liver. After informing the couple of the extremely poor prognosis, medical termination of pregnancy was requested. Pathologic examination of the conjoined female fetuses revealed a single, non-duplicated heart, two livers connected at the right lobe, completely separate bile ducts and digestive tract, and a single placenta and umbilical cord containing two arteries and six veins. The karyotype was normal. Diagnostic ultrasound criteria for thoracopagus conjoined twins include: the relative position of the two fetuses facing each other, hyperextension of the cervical spine, continuity of the skin and mirror image body parts with limbs close together. The presence of a single heart, liver and umbilical cord, all of increased size, confirms the diagnosis. Various degrees of fetal fusion result from incomplete division of the inner cell mass 13 to 15 days after fertilization. Although the precise causes are unknown, many workers believe that the factors responsible for monozygosity may also play a role in conjoined twins. In Switzerland, 1% of all live births are twins with approximately 1/4 of these monozygotic. If incomplete division of the inner cell mass occurs in 1% of these cases, the estimated incidence of conjoined twins is 1/40000 births. Although thoracopagus twins are more frequent, omphalopagus twins are more commonly encountered at birth, due to lower fetal mortality. The overall prognosis depends on the degree of organ sharing between fetuses. Very few surgically separated thoracopagus conjoined twins have lived and those who did survive had separate hearts. Also, conjoined twins can cause dystocia with the risk of rupture of the uterus, and often require cesarean section which may have negative consequences for the obstetrical future of the mother. However, an early ultrasound diagnostic can modify prognosis and allow medical termination of pregnancy in the case of seriously malformed thoracopagus conjoined twins. The risk that the condition recurs in a subsequent pregnancy may be considered negligible.