M. Essaoui

Laser therapy for twin-to-twin transfusion syndrome (TTTS).

Monochorionic twins are subjected to specific complications which originate in either imbalance or abnormality of the single placenta serving two twins including twin‐to‐twin transfusion syndrome. The diagnosis is well established in overt clinical forms with the association of polyuric polyhydramnios and oliguric oligohydramnios. The best treatment of cases presenting before 26 weeks of gestion is fetoscopic laser ablation of the intertwin anastomoses on the chorionic plate. Although subjected to subtle variations, the core technique follows robust guidelines which could help understanding and acquiring the required skills and experience to perform this procedure. However appropriate and tailored hands‐on training and appropriate perinatal set‐up are critical not only for surgical management but also for the follow‐up and management of related complications. Copyright

Active management of selective intrauterine growth restriction with abnormal Doppler in monochorionic diamniotic twin pregnancies diagnosed in the second trimester of pregnancy.

This study aims to compare outcomes of active management of monochorionic diamniotic twin pregnancies complicated with severe intrauterine growth restriction (IUGR) of one twin before 24 weeks with continuous or intermittent absent or reversed end‐diastolic flow (AREDF) in the umbilical artery, with or without twin‐to‐twin transfusion syndrome (TTTS).

Pulmonary stenosis in complicated monochorionic twin pregnancies: prevalence, management and outcome

To review prevalence, management and prognostic factors of pulmonary stenosis (PS) in monochorionic diamniotic (MCDA) pregnancies complicated by twin‐to‐twin transfusion syndrome (TTTS).

OC22.08: Brain lesions diagnosed prenatally following laser coagulation for twin‐twin transfusion syndrome

Objectives: (i) To describe the types of fetal brain lesions developing following fetoscopic laser ablation of communicating vessels in twintwin transfusion syndrome (TTS) and (ii) to analyse the lesions based on gestational age at diagnosis of TTS and at surgery to understand further the underlying pathophysiology. Methods: Retrospective study of all cases of laser ablation for TTTS performed between January 1999 and March 2012. The cases were retrieved via interrogation of ASTRAIA database. The fetoscopy was performed within 48 hours of diagnosis of TTTS. Weekly surveillance was implemented up until delivery. In addition fetal MRI was routinely performed at 32 weeks in all cases unless lesions were suspected on ultrasound earlier. Results: 948 laser ablations were performed. Of these, 27 (3%) were followed by the development of brain lesions. Eight different types of lesions were observed, including: ischemic (1), hemorrhagic (8), ventriculomegaly (7), white matter calcifications (1), schizencephaly (5), atrophy (4), periventricular leukomalacia (1), massive dysgenesis (1). In 7 cases (25.9%) the cerebral lesions were visible within two weeks of the fetoscopy. 4 cases (14.8%), were only diagnosed by MRI. The recipient was more likely to be affected than the donor twin. Conclusions: Brain lesions developed in 3% compared to 10–20% reported in the literature. One quarter were visible within two weeks of the procedure. Underlying pathophysioogyl include prematurity, growth restriction, anaemia and hemodynamic imbalance. The multiple contributing factors may explain the diversity of these lesions.

OC22.06: Discordant anomalies in monochorionic twins

Methods: Retrospective cohort of 453 twin pregnancies in two tertiary centers over an 11-year period. All women had serial ultrasound assessment of CL from 11–13+6 weeks through to 14–15+6, 16–17+6, 18–19+6 and 20–21+6 weeks as part of routine antenatal care. A total of 720 serial CL measurements were recorded. Monochorionic twin pregnancies complicated with twin to twin transfusion syndrome and monoamniotic pregnancies were excluded. We estimated the association between cervical length at each of the five study periods and preterm delivery before 28, 32 and 34 weeks’ respectively. Results: The cumulative incidence of preterm delivery was 6.8%, 13.2% and 26.1% before 28, 32 and 34 weeks’ respectively. A CL below 50 mm at 11–13+6 weeks was associated with preterm delivery before 28 weeks (RR = 1.63, 95% CI = 1.21–2.18, P 45 mm for delivery before 28 (LR− 0.33) and 34 weeks (LR− 0.29) respectively. CL 50 mm at this gestation reflects a low likelihood of preterm delivery.

OP17.03: Perinatal outcome of monochorionic twins with severe selective IUGR

Objectives: To determine whether a previous good response to IVIG treatment in pregnant women with neonatal alloimmune thrombocytopenia (NAIT) predicts a similar response in the next affected pregnancy. Methods: Thirty-six pregnancies in 24 women were managed by weekly administration of IVIG without monitoring platelet counts. Seven women had more than one pregnancy treated by IVIG resulting in 18 consecutive treated pregnancies. Results: The mean platelet count at the first affected pregnancy was 28,000/μL and the mean platelet count at birth following IVIG treatment was 126,000/μL. Four (11%) of the treated fetuses had a platelet count of < 30,000/ μL at birth. Four women with two pregnancies treated by IVG and one woman with three pregnancies treated by IVIG had a good response with platelet count at birth above 50,000/μL in all their pregnancies. One woman had an adequate response in her first two treated pregnancies but in her third pregnancy the platelet count at birth was 11,000/μL. Similarly, another patient delivered a thrombocytopenic infant with platelet count of 39,000/μL following 3 previous pregnancies in which a good response to IVIG has been achieved. None of pregnancies in our cohort has been complicated by intra-cerebral hemorrhage. Conclusions: A good response to IVIG in one pregnancy with NAIT does not guarantee effectiveness of treatment in the next affected pregnancy. The possibility of developing intolerance to IVIG treatment following recurrent pregnancies, which were successfully treated by IVIG, should be considered.