Uncomplicated Monochorionic Research Articles

Long-Term Neurodevelopmental Outcome After Selective Fetoscopic Laser Therapy for Stage I Twin-Twin Transfusion Syndrome.

Twin-twin transfusion syndrome (TTTS) is a serious complication in monochorionic (MC) pregnancies. Fetoscopic laser surgery (FLS) is the primary treatment for advanced TTTS, but managing Quintero stage I TTTS is still controversial. We conducted an observational study evaluating the 2-year neurodevelopment of fetuses, which underwent FLS for stage I TTTS, compared with advanced TTTS and uncomplicated monochorionic diamniotic twins (MCDTs). The study included 156 children: 14 in stage I TTTS group, 28 in advanced TTTS group, and 114 in uncomplicated twin group. In stage I TTTS, 92.9% showed normal neurodevelopment, with no severe neurological impairments observed. These results were comparable with uncomplicated twins (92.1% normal neurodevelopment, P = .921, adjusted odds ratio [aOR] = 1.56, 95% confidence interval [CI] = 0.42-5.79; 1.8% severe impairment, P = .617). Advanced TTTS had a non-significant lower rate of normal neurodevelopment (89.3%, P = .710, aOR = 1.31, 95% CI = 0.12-14.87). In conclusion, FLS for stage I TTTS shows favorable long-term neurodevelopmental outcomes, similar to uncomplicated MC pregnancies.

Two Year Neurodevelopmental Outcome after Fetoscopic Laser Therapy for Twin-Twin Transfusion Syndrome: Comparison with Uncomplicated Monochorionic Diamniotic Twins.

Twin-twin Transfusion Syndrome (TTTS) represents a significant complication in monochorionic twin pregnancies, caused by an unbalanced shunting of blood through intertwin placental vascular anastomoses. Despite advances in fetoscopic laser surgery, TTTS is still associated with a high rate of cerebral injury. However, there are no studies comparing these pregnancies with uncomplicated monochorionic diamniotic (MCDA) twin pregnancies, establishing the baseline risk of neurodevelopmental impairment. The aim of this study is to evaluate the odds of neurodevelopmental impairment in MCDA twins who undergo fetoscopic laser surgery for twin-twin transfusion syndrome, in comparison to a cohort of uncomplicated MCDA twin pregnancies. This is a retrospective cohort study of children born from MCDA twin pregnancies at a single center between 2008 and 2019. A routine, standardized follow-up assessment was conducted at a minimum of 2 years after delivery. The primary outcome of this was a 2 year neurodevelopmental impairment. Neurological, motor, and cognitive development was assessed by using the revised Brunet-Lézine scale. 176 children met the enrolment criteria. Of these, 42 (24%; TTTS group) underwent fetoscopic laser surgery for TTTS during pregnancy, and 134 (76%; uncomplicated MCDA group) were uncomplicated MCDA pregnancies. The primary outcome was found in four children (9.52%) in the TTTS group and ten children (7.46%) in the uncomplicated MCDA group (p = 0.67, aOR 2.82, 95% CI 0.49-16.23). Major neurologic impairment was found in 2.38% after fetoscopic laser surgery and 1.49% in uncomplicated MCDA twins (p = 0.70, aOR 0.97, 95% CI 0.22-4.24). The data were adjusted by birth order, birth weight, and gestational age at birth. The outcome in MCDA twins who underwent fetoscopic laser surgery for TTTS is comparable to the outcome in uncomplicated MCDA twins. Our findings emphasize the need for long-term neurodevelopmental follow-ups in all children from monochorionic twin gestations.

Comparative Study of Perinatal Outcome in Uncomplicated Monochorionic Diamniotic versus Dichorionic Diamniotic Twins at a Specialized Twin Clinic—A Prospective Study

Abstract Background Monochorionic twins have higher perinatal morbidity and mortality than dichorionic twins. However, there is conflicting data on outcomes of uncomplicated monochorionic twins. Purpose of the Study The aim of this study is to compare the outcomes of apparently uncomplicated monochorionic twins to dichorionic twins. Methods This is a prospective study conducted from August 2019 to December 2020 at a specialized twin clinic. All twins, whose chorionicity was determined before 14 weeks with two live fetuses at 24 weeks, were recruited. Complicated monochorionic diamniotic (MCDA) twins with twin-to-twin transfusion syndrome, twin anemia polycythemia syndrome, selective fetal growth restriction before 24 weeks and single or double fetal demise before 24 weeks were excluded. Other exclusion criteria were major congenital and chromosomal abnormalities, higher order multiples, monoamniotic twins, and twins with undetermined chorionicity antenatally. Both the groups were followed till delivery and neonates followed till 28 days. Maternal and neonatal outcomes were studied and compared. Results One-hundred forty-eight mothers with dichorionic diamniotic (DCDA) and 74 with uncomplicated MCDA were studied. Mean gestational age at delivery was 35 weeks in both the groups. Maternal, fetal, and neonatal morbidities were similar in both, except early onset preeclampsia that was higher in the DCDA group. Prospective risk of stillbirth for DCDA and MCDA after 24 weeks was 1.35 and 4.05%, respectively. Prospective risk of stillbirth for DCDA and MCDA after 30 weeks was 1.49 and 0%, respectively. Conclusion The maternal and perinatal outcomes in uncomplicated MCDA twins are similar to DCDA twins. Prospective risk of stillbirth after 30 weeks is extremely low. Hence, uncomplicated MCDA twins should not be delivered electively before 36 weeks.

460: Additional value of delta MCA-PSV to predict TAPS

The aim of this study was to investigate the predictive value of delta Middle Cerebral Artery- Peak Systolic Velocity (MCA-PSV) > 0.5 compared to currently used cut-off MCA-PSV for the postnatal diagnosis of Twin Anemia Polycythemia sequence (TAPS). This retrospective study involved a consecutive cohort comprising uncomplicated monochorionic (MC) twins and twins with a postnatal TAPS diagnosis between 2004 and 2016 in a Dutch national referral center for fetal therapy. The accuracy to predict postnatal TAPS with currently used cut-off MCA-PSV or delta MCA-PSV (measured within a week prior to cord or neonatal blood sampling) was assessed using 2x2 tables. In total, 45 uncomplicated MC and 35 TAPS twins were analyzed. The sensitivity and specificity of cut-off MCA-PSV to predict a postnatal TAPS diagnosis were 46% (95% CI, 29-63%) and 100% (95% CI, 92-100%), respectively; positive predictive value was 100% and negative predictive value 70% (95%, 64-76%). Delta MCA-PSV showed a sensitivity of 83% (95% CI, 66-93%) and a specificity of 98% (95% CI, 88-100%); the positive predictive value and negative predictive value were 97% (95% CI, 81-100%) and 88% (95%, 88-94%), respectively. Out of the 35 cases with postnatal TAPS, 13 twin pairs had only a delta MCA-PSV diagnosis and no cut-off MCA-PSV diagnosis. Out of these 13 TAPS twins, 9 donors and 4 recipients had normal MCA-PSV. This study shows that delta MCA-PSV > 0.5 MoM is of additional value for predicting postnatal TAPS. In case of delta MCA-PSV > 0.5 in Doppler ultrasound, obstetricians should be aware of the therapeutic implications and neonatal morbidities associated with TAPS.

C4. Maternal cardiac changes during uncomplicated twin pregnancy: does the chorionicity matter?

Objectives: To assess longitudinally the echocardiographic findings in a cohort of women carrying an uncomplicated monochorionic (MC) twin pregnancy and compare them with those obtained from dichorionic (DC) twin gestations.Methods: Healthy women with MC twin pregnancies were submitted to serial transthoracic maternal echocardiography during the first, second and third trimester. Cases with severe obstetric complications after enrollment were eventually excluded. The cardiac findings obtained at different time frames within the MC group were compared. Moreover, these data were compared with those obtained longitudinally in a cohort of uncomplicated DC twin pregnancies.Results: From 2012 to 2016, 19 women with an uncomplicated MC twin pregnancy were included in this study group. Among this group no significant changes were documented from 1st to 3rd trimester with the exception of an ejection fraction decrease. In respect of 48 DC uneventful twin gestations in the MC set the following significant differences were observed: reduced cardiac output (midtrimester) and ejection fraction (1st and 2nd trimester), increased total vascular resistance (1st trimester). Regarding the diastolic function in the MC versus DC twins a significant increase of the following parameters was noted: mitral valve E/A (early diastolic – atrial contraction) ratio (3rd trimester); MSE1 (1st and 2nd trimester), MS E1/A1 (3rd trimester); ML E1 (2nd and 3rd trimester); ML E1/A1 (3rd trimester). The longitudinal trend of the following data showed a significant difference between the MC and the DC set: increase of ML E1 and MLE1/A1, decrease of ML A1.Conclusions: In uncomplicated MC twin pregnancies maternal cardiac changes seem to differ significantly from the DC set. In particular, in the former group the diastolic function impairment is less pronounced presumably due to the lower circulating volume.

Impact of Monochorionicity and Twin to Twin Transfusion Syndrome on Prenatal Attachment, Post Traumatic Stress Disorder, Anxiety and Depressive Symptoms.

Monochronioric (MC) twin pregnancies are considered as high-risk pregnancies with potential complications requiring in-utero interventions. We aimed to assess prenatal attachment, anxiety, post-traumatic stress disorder (PTSD) and depressive symptoms in MC pregnancies complicated with Twin-To-Twin-transfusion syndrome (TTTS) in comparison to uncomplicated monochorionic (UMC) and dichorionic pregnancies (DC). Auto-questionnaires were filled out at diagnosis of TTTS and at successive milestones. Prenatal attachment, PTSD, anxiety and perinatal depression were evaluated respectively by the Prenatal Attachment Inventory (PAI) completed for each twin, the Post-traumatic Checklist Scale (PCLS), the State-Trait Anxiety Inventory (STAI) and the Edinburgh Perinatal Depression Scale (EPDS). There was no significant difference in the PAI scores between the two twins. In the DC and UMC groups, PAI scores increased throughout pregnancy, whilst it didn’t for TTTS group. TTTS and DC had a similar prenatal attachment while MC mothers expressed a significantly higher attachment to their fetuses and expressed it earlier. At the announcement of TTTS, 72% of the patients present a score over the threshold at the EPDS Scale, with a higher score for TTTS than for DC (p = 0.005), and UMC (p = 0.007) at the same GA. 30% of mothers in TTTS group have PTSD during pregnancy. 50% of TTTS- patients present an anxiety score over the threshold (STAI-Scale), with a score significantly higher in TTTS than in UMC (p<0.001) or DC (p<0.001). The proportion of subject with a STAI–State over the threshold is also significantly higher in TTTS than in DC at 20 GW (p = 0.01) and at 26 GW (p<0.05). The STAI-state scores in UMC and DC increase progressively during pregnancy while they decrease significantly in TTTS. TTTS announcement constitutes a traumatic event during a pregnancy with an important risk of PTSD, high level of anxiety and an alteration of the prenatal attachment. These results should guide the psychological support provided to these patients.

Neonatal outcome of late preterm uncomplicated monochorionic twins: what is the optimal time for delivery?

Objective: To determine the neonatal outcome at late prematurity of uncomplicated monochorionic (MC) twin pregnancies.Methods: A retrospective cohort study of 166 patients with uncomplicated MC diamniotic twins delivered between 34 and37 weeks of gestation at a single tertiary center. The study population was classified into four groups according to the gestational age at delivery: (1) 34 weeks, (2) 35 weeks, (3) 36 weeks and (4) 37 weeks. Neonatal outcome measures were compared between the groups.Results: Neonatal morbidity was significantly higher at 34 weeks of gestation compared to the other three groups including respiratory distress syndrome, oxygen requirement, hypothermia and hyperbilirubinemia. Moreover, the rate of admission to the special care unit and need for phototherapy were significantly higher in newborns born at 36 weeks compared to 37 weeks of gestation (p = 0.02 and 0.03 respectively). Multiple regression analysis revealed that the risk for adverse neonatal outcome was significantly associated with gestational age at delivery. Of note, there were no fetal or neonatal deaths in our cohort.Conclusions: The risk of neonatal morbidity of uncomplicated MC twins delivered at 34–37 weeks of gestation significantly decreases with advanced gestation. Therefore, under close fetal surveillance, uncomplicated MC twin pregnancies should be delivered at 37 weeks of gestation.

Uncomplicated Monochorionic Twins––Is Elective Preterm Delivery Mandatory?

AbstractOften (50 % times), twin pregnancy is complicated by preterm vaginal delivery which may be due to spontaneous labor or due to medical conditions. However, it remains a debatable issue as what to do in a situation of continuing uncomplicated twin pregnancy. Some investigators suggest that because of increased risk of unexplained fetal demise after 32 weeks, elective preterm delivery should be carried out. However, there is no conclusive evidence to support or refute this suggestion and there is always a dilemma whether to allow these patients to go in spontaneous labor till term or to deliver before that. In the absence of clear evidence, it is reasonable to keep uncomplicated monochorionic twin pregnancies under close follow-up and to deliver them at 38 weeks of gestation.

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

OBJECTIVE:To determine the optimum timing for planned delivery of uncomplicated monochorionic and dichorionic twin pregnancies.METHODS:Unselected twin pregnancies were recruited for this prospective cohort study (N=1,028), which was conducted in eight tertiary referral perinatal centers in Ireland.

Mode of delivery and neonatal outcome in uncomplicated monochorionic twin pregnancies

Objective: The association between of mode of delivery and perinatal morbidity in monochorionic (MC) twins is not clear. Thus there is no agreement regarding the optimal mode of delivery of MC twins. The aim of this study is to determine the impact of the mode of delivery on neonatal outcome of uncomplicated MC twins in a tertiary center with a strict policy of delivering MC twins by 37 weeks’ gestation. Methods: Retrospective analysis of all uncomplicated MC twin deliveries at a tertiary referral hospital during a 5-year period. Complicated MC pregnancies (fetal death, selective reduction, twin to twin transfusion syndrome, fetal growth restriction of one or both twins or major fetal anomalies) were excluded. Induction of labor or planned caesarean sections of uncomplicated MC pregnancies was conducted between 35 and 37 weeks of gestation. Neonatal outcomes of MC twins were compared according to the mode of delivery. Moreover, mode of delivery was compared with a control group of 1934 dichorionic (DC) twin pregnancies delivered during the same period. Results: The rate of Caesarean section was 63.4% in uncomplicated MC/DA twins pregnancies and this was similar to our rate in DC twins (61%, p = 0.65). Multivariate analysis revealed that adverse neonatal outcome was significantly associated with gestational age at delivery, neonatal birth weight discordance and male gender but not with the intended or actual mode of delivery. Conclusion: Delivering MC twin pregnancies by 37 weeks’ gestation is associated with similar rate of vaginal deliveries compared with DC twin pregnancies. The neonatal outcome was not affected by the mode of delivery, and therefore vaginal delivery seems safe in MC twins.

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

Department of Obstetrics and Gynecology, Dartmouth-Hitchcock Medical Center, Lebanon, New Hampshire Financial Disclosure: The authors did not report any potential conflicts of interest.

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

Royal College of Surgeons in Ireland, Rotunda Hospital, Dublin, Ireland Financial Disclosure: The authors did not report any potential conflicts of interest.

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

To determine the optimum timing for planned delivery of uncomplicated monochorionic and dichorionic twin pregnancies. Unselected twin pregnancies were recruited for this prospective cohort study (N=1,028), which was conducted in eight tertiary referral perinatal centers in Ireland. Perinatal mortality and a composite measure of perinatal morbidity (respiratory distress, necrotizing enterocolitis, hypoxic ischemic encephalopathy, periventricular leukomalacia, or sepsis) were compared between uncomplicated twins that underwent planned preterm delivery compared with monochorionic twins that continued in utero beyond 34 weeks of gestation, and dichorionic twins who continued beyond 36 weeks. Perinatal outcome data were recorded for 100% of the 1,001 twin pairs that completed the study (n=200 monochorionic and n=801 dichorionic). Overall perinatal mortality was 30 per 1,000 in monochorionic twins and 3.8 per 1,000 among dichorionic twins. The prospective risk of in utero death was 1.5% after 34 weeks of gestation for uncomplicated monochorionic pregnancies, with no deaths among dichorionic twins after 33 weeks. The risk of a composite measure of perinatal morbidity for uncomplicated monochorionic twins fell from 41% (13/32 neonates, 3/6 among elective deliveries) at 34 weeks to 5% (4/84) at 37 weeks (P<.001). Among dichorionic twins, the risk of morbidity fell from 4% (2/52) among elective deliveries at 36 weeks to 1% (5/344) in pregnancies continuing to 38 weeks (P=.231). Applying a strategy of close fetal surveillance, perinatal morbidity can be minimized by allowing uncomplicated monochorionic pregnancies continue to 37 weeks of gestation and dichorionic twins to 38 weeks. Among monochorionic twins, this approach must be balanced against a 1.5% risk of late in utero death.

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

Optimum Timing for Planned Delivery of Uncomplicated Monochorionic and Dichorionic Twin Pregnancies

Perinatal Outcome of Monochorionic Twins With Selective IUGR Compared With Uncomplicated Monochorionic Twins

To evaluate the perinatal outcome of MC twins with selective IUGR (sIUGR). A prospective study, which included three groups of MC twins: Group A, uncomplicated MC twin pregnancies (n = 91); group B, sIUGR with normal umbilical artery Doppler (n = 19); and group C, sIUGR with abnormal (absence or reversed EDV) umbilical artery Doppler (n = 18). The latter were routinely hospitalized in the high-risk ward under strict surveillance. Neonatal outcome of fetuses complicated with sIUGR and normal Doppler was similar to controls. Neonates born to pregnancies complicated by sIUGR and abnormal Doppler had significantly increased incidence of CNS findings, RDS, NEC, sepsis, and neonatal death compared to controls. Adverse outcome in this group was independently associated only with gestational age at birth. The perinatal outcomes of MC twins complicated with sIUGR and normal Doppler are similar to uncomplicated MC pregnancies. MC twins with sIUGR and abnormal Doppler have reasonable outcomes, yet significantly more neonatal complications compared to non-complicated MC twins.

The value of umbilical artery Doppler velocimetry in the antenatal surveillance of uncomplicated monochorionic twin pregnancies

To investigate the predictive value of abnormal umbilical artery Doppler findings on outcome in uncomplicated monochorionic (MC) twin pregnancies. Sixty-seven MC twin pregnancies, with antenatal care and delivery at the University Medical Center, Utrecht, The Netherlands, between 1999 and 2004, were studied. Pregnancies with antenatal signs of twin-to-twin transfusion syndrome were excluded. We analyzed the data according to both the last Doppler measurement of the umbilical artery before delivery and the presence of any abnormal Doppler measurement during the course of pregnancy. Risks of mortality and total neonatal morbidity were stratified according to the Doppler findings in one or both fetuses at the time of each standard ultrasound assessment in order to estimate the risk associated with an abnormal Doppler finding at or before that specific gestational age. Mortality rates were similar in the normal and abnormal Doppler groups. Using both group definitions, total neonatal morbidity was higher in the abnormal Doppler group; this was significant at > 32 weeks' gestation, and was due to lower birth weight and earlier gestational age at delivery. There was no mortality at > or = 36 weeks in the abnormal Doppler group, but there were four perinatal deaths in the normal Doppler group. Gestational age at delivery was significantly lower when one or more abnormal Doppler findings had been present (median, 34 + 1 weeks vs. 36 + 3 weeks) and infants with abnormal Doppler findings weighed on average 261 g (95% CI, 21-502 g) less than those with normal findings. In MC twins, abnormal Doppler flow of the umbilical artery identifies a subgroup at risk for preterm delivery, low birth weight and neonatal morbidity, but with a similar mortality risk to those with normal Doppler flow. At term, mortality occurred only in the group with normal Doppler findings, suggesting that fetal surveillance is insufficient in uncomplicated term MC twin pregnancies.

Twin chorionicity and the risk of adverse perinatal outcome

Objective: To evaluate the impact of chorionicity on the perinatal outcomes of twin pregnancies complicated by twin–twin transfusion syndrome (TTS) or selective intrauterine growth restriction (sIUGR). Method: Pregnancies with 127 monochorionic (MC) and 109 dichorionic (DC) twins were followed up, and TTS and sIUGR incidence as well as morbidity and mortality were evaluated. Results: The incidence of intrauterine fetal death was higher in MC than in DC pregnancies (6.5% vs. 1%), and higher in MC pregnancies complicated by TTS (5 deaths in 10 pregnancies [50%]) or sIUGR (2 in 9 [22%]). The incidence of sIUGR was similar in MC and DC pregnancies (7% vs. 5%), and the incidence of TTS was 8% in MC pregnancies (95% confidence interval, 3.2–12.8). Neonatal neurological and respiratory morbidity was higher among MC twins, and the increase in neonatal complications was linked to TTS and sIUGR. Uncomplicated MC and DC pregnancies had similar perinatal outcomes. Conclusion: The incidence of neonatal complications was higher in MC twins born of pregnancies complicated by TTS or sIUGR. Although the incidence of sIUGR was similar in MC and DC pregnancies, there was a trend towards worse outcomes in MC pregnancies affected by sIUGR.

Uncomplicated Monochorionic Diamniotic Twins and the Timing of Delivery

Cleary-Goldman and d'Alton discuss the implications of a new study in PLoS Medicine examining the risk of fetal death in uncomplicated monochorionic diamnotic twin pregnancies.