Objectives To report the outcome of selective fetal growth restriction (sFGR) diagnosed according to the new Delphi consensus definition, and determine potential predictors of survival, in a cohort of unselected monochorionic diamniotic twin pregnancies. Methods This was a retrospective study of monochorionic diamniotic twin pregnancies followed from the first trimester onward, which were diagnosed with sFGR at 16, 20 or 30 weeks' gestation. sFGR was defined according to the new Delphi consensus criteria as presence of either an estimated fetal weight (EFW) < 3rd centile in one twin or at least two of the following: EFW of one twin < 10th centile, abdominal circumference of one twin < 10th centile, EFW discordance ≥ 25% or umbilical artery pulsatility index of the smaller twin > 95th centile. The primary outcomes were the overall survival rate (up to day 28 after birth) and risk of loss of one or both twins. We further determined possible predictors of survival using uni‐ and multivariate generalized estimated equation modeling. Results We analyzed 675 pregnancies, of which 177 (26%) were diagnosed with sFGR at 16, 20 or 30 weeks. The overall survival rate was 313/354 (88%) with 146/177 (82%) pregnancies resulting in survival of both twins, 21/177 (12%) in survival of one twin and 10/177 (6%) in loss of both twins. Subsequent twin anemia–polycythemia sequence (TAPS) developed in 6/177 (3%) and twin–twin transfusion syndrome (TTTS) in 17/177 (10%) pregnancies. All TAPS fetuses survived. The survival rate in sFGR pregnancies that subsequently developed TTTS was 65% (22/34), compared with 91% (279/308) in those with isolated sFGR (no subsequent TAPS or TTTS) (P < 0.001). The majority of sFGR cases were Type I (110/177 (62%)) and had a survival rate of 96% (212/220), as compared with a survival of 55% (12/22) in those with Type‐II (P < 0.001) and 83% (55/66) in those with Type‐III (P = 0.006) sFGR. The majority of sFGR pregnancies (130/177 (73%)) were first diagnosed at 16 or 20 weeks (early onset), with a survival rate of 85% (221/260), as compared with a survival of 98% (92/94) in sFGR first diagnosed at 30 weeks (late onset) (P = 0.04). A major anomaly in at least one twin was present in 28/177 (16%) sFGR cases. In these pregnancies, survival was 39/56 (70%), compared with 274/298 (92%) in those without an anomaly (P < 0.001). Subsequent development of TTTS (odds ratio (OR), 0.18 (95% CI, 0.06–0.52)), Type‐II sFGR (OR, 0.06 (95% CI, 0.02–0.24)) and Type‐III sFGR (OR, 0.21 (95% CI, 0.07–0.60)) and presence of a major anomaly in at least one twin (OR, 0.12 (95% CI, 0.04–0.34)), but not gestational age at first diagnosis, were independently associated with decreased survival. Conclusions Isolated sFGR is associated with a 90% survival rate in monochorionic diamniotic twin pregnancies. The subsequent development of TTTS, absent or reversed end‐diastolic flow in the umbilical artery of the smaller twin and the presence of a major anomaly adversely affect survival in sFGR. Copyright © 2020 ISUOG. Published by J...

1 December 2003.

Velamentous cord insertion in one or both twins increases the risk of adverse outcome and TTTS, irrespective of discordance in the insertion sites, whereas the risk of discordant growth is determined by both discordance in insertion sites and velamentous cord insertion in one twin. Copyright © 2017 ISUOG. Published by John Wiley & Sons Ltd.

In this multicenter study of 328 twin pregnancies with Type-III selective intrauterine growth restriction (sIUGR), fetal death complicated 11% of them. At viability, mortality rates were very low (< 2% at 28 weeks). Delivery at 32 weeks was associated with a high rate of adverse neonatal outcome, which substantially decreased at 34 weeks (11%), with a very low risk of fetal death (0.7%). What are the clinical implications of this work? With close fetal surveillance, the risk of unexpected fetal death in Type-III sIUGR may be lower than reported previously. Further multicenter studies are needed to assess which factors truly predict fetal death, in order to allow for optimal pregnancy management.

Objective To compare the outcome of monochorionic diamniotic (MCDA) twin pregnancies conceived by in‐vitro fertilization (IVF) or intracytoplasmic sperm injection (ICSI) with that of spontaneously conceived MCDA twins. Methods This was a retrospective cohort study of MCDA twin pregnancies conceived after IVF/ICSI or spontaneously, followed from the first trimester onwards at a single center between January 2002 and September 2018. The primary outcome was survival per fetus from the first trimester until 28 days after birth. Secondary outcome measures were number of survivors, miscarriage, termination of pregnancy, intrauterine and neonatal death, major congenital anomalies, twin–twin transfusion syndrome, selective fetal growth restriction, gestational age at birth, delivery before 32 weeks' gestation, mode of delivery, admission to the neonatal intensive care unit, birth weight and birth‐weight discordance. Results Of the 654 MCDA pregnancies included in the analysis, 80 were conceived by IVF/ICSI and 574 spontaneously. Overall fetal and neonatal survival was significantly lower in the IVF/ICSI group than in the spontaneous‐conception group (79% vs 90%; P = 0.001). In the IVF/ICSI group, compared with the spontaneous‐conception group, loss of one or both twins occurred twice as often (29% vs 14%; P = 0.001) and there was a higher risk of second‐trimester miscarriage (8% vs 1%; P = 0.002). Conclusions MCDA twins conceived after IVF/ICSI have lower overall survival rates and higher rates of second‐trimester miscarriage than do spontaneously conceived MCDA twins. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Twin-to-twin transfusion syndrome (TTTS) and twin anemia polycythemia sequence (TAPS) are complications unique to monochorionic twin pregnancies and their shared circulation. Both are the result of the transfusion imbalance in the intertwin circulation. TTTS is characterized by an amniotic fluid discordance, whereas in TAPS, there is a severe discordance in hemoglobin levels. The article gives an overview of the typical features of TTTS and TAPS placentas.

Due to the increased risk of antenatal brain lesions, we offer a third-trimester magnetic resonance imaging (MRI) scan to all patients who underwent an in utero intervention for twin-twin transfusion syndrome (TTTS). However, the usefulness of such a policy has not been demonstrated yet. Therefore, we determined the prevalence of antenatal brain lesions detected on third-trimester MRI and the proportion of lesions detected exclusively on MRI. Materials and MethodsWe conducted a retrospective cohort study of monochorionic diamniotic twin pregnancies complicated by TTTS that underwent laser coagulation of the vascular anastomoses or fetal reduction by umbilical cord occlusion between 2010 and 2017. We reviewed the third-trimester MRI findings and compared those with the prenatal ultrasonography. ResultsOf the 141 patients treated with laser coagulation and 17 managed by cord occlusion, 112/141 (79%) and 15/17 (88%) patients reached 28 weeks. Of those, 69/112 (62%) and 11/15 (73%) underwent an MRI between 28 and 32 weeks. After laser coagulation, MRI detected an antenatal brain lesion in 6 of 69 pregnancies (9%) or in 6 of 125 fetuses (5%). In 4 cases (67%), the lesion was detected only on MRI.In the 11 patients treated with cord occlusion, no brain lesions were diagnosed. ConclusionThe prevalence of brain lesions detected by third-trimester MRI is higher compared to prenatal ultrasonography alone, making MRI appears a useful adjunct to detect antenatal brain lesions in twin pregnancies after in-utero treatment for TTTS.Third-trimester MRI TTTS Aertsen et al.

Novel transvaginal ultrasound (TVU) markers have been proposed to improve spontaneous preterm birth (sPTB) prediction. Preliminary results of the cervical consistency index (CCI), uterocervical angle (UCA), and cervical texture (CTx) have been promising in singletons. However, in twin pregnancies, the results have been inconsistent. In this prospective cohort study of asymptomatic twin pregnancies assessed between 18+0–22+0 weeks, we evaluated TVU derived cervical length (CL), CCI, UCA, and the CTx to predict sPTB < 34+0 weeks. All iatrogenic PTB were excluded. In the final cohort of 63 pregnancies, the sPTB rate < 34+0 was 16.3%. The CCI, UCA, and CTx, including the CL was significantly different in the sPTB < 34+0 weeks group. The best area under the receiver operating characteristic curve (AUC) for sPTB < 34+0 weeks was achieved by the CCI 0.82 (95%CI, 0.72–0.93), followed by the UCA with AUC 0.72 (95%CI, 0.57–0.87). A logistic regression model incorporating parity, chorionicity, CCI, and UCA resulted in an AUC of 0.91 with a sensitivity of 55.3% and specificity of 88.1% for predicting sPTB < 34+0. The CCI performed better than other TVU markers to predict sPTB < 34+0 in twin gestations, and the best diagnostic accuracy was achieved by a combination of parity, chorionicity, CCI, and UCA.