Dichorionic Diamniotic Twin Anencephaly and Exencephaly.

We present a rare case of dichorionic diamniotic twin anencephaly and exencephaly discovered in a 35-year-old female at 13.1 weeks of gestation. Anencephaly and exencephaly are neural tube defects (NTD) with devastating consequences caused by the failure of the anterior neural groove closure leading to exencephaly, followed by brain disintegration causing anencephaly. While NTD themselves are common congenital anomalies, their presence in both twins of a dichorionic diamniotic gestation is exceedingly rare and has only been documented in one other instance. The uncertainty surrounding risk factors involved in this specific case underscores the importance of ongoing research to elucidate other potential determinants in the pathogenesis of NTD and to discover novel preventive strategies, particularly in twin pregnancies. Future research endeavors should explore the interplay of genetic, environmental, and other anomalous factors to deepen our understanding and improve clinical outcomes for affected pregnancies.

Perinatal outcomes between immediate vs deferred selective termination in dichorionic twin pregnancies with fetal congenital anomalies: a French multicenter study.

BACKGROUND: Because selective termination for discordant dichorionic twin anomalies carries a risk of pregnancy loss, deferring the procedure until the third trimester can be considered in settings where it is legal. OBJECTIVE: To determine whether perinatal outcomes were more favorable following deferred rather than immediate selective termination. STUDY DESIGN: A French multicenter retrospective study from 2012 to 2023 on dichorionic twin pregnancies with selective termination for fetal conditions, which were diagnosed before 24 weeks gestation. Pregnancies with additional risk factors for late miscarriage were excluded. We defined 2 groups according to the intention to perform selective termination within 2 weeks after the diagnosis of the severe fetal anomaly was established (immediate selective termination) or to wait until the third trimester (deferred selective termination). The primary outcome was perinatal survival at 28 days of life. Secondary outcomes were pregnancy losses before 24 weeks gestation and preterm delivery. RESULTS: Of 390 pregnancies, 258 were in the immediate selective termination group and 132 in the deferred selective termination group. Baseline characteristics were similar in both groups. Overall survival of the healthy co-twin was 93.8% (242/258) in the immediate selective termination group vs 100% (132/132) in the deferred selective termination group (P<.01). Preterm birth <37 weeks gestation was lower in the immediate than in the deferred selective termination group (66.7% vs 20.2%; P<.01); preterm birth <28 weeks gestation and <32 weeks gestation did not differ significantly (respectively 1.7% vs 0.8%; P=.66 and 8.26% vs 11.4%; P=.36). In the deferred selective termination group, an emergency procedure was performed in 11.3% (15/132) because of threatened preterm labor, of which 3.7% (5/132) for imminent delivery. CONCLUSION: Overall survival after selective termination was high regardless of the gestational age at which the procedure was performed. Postponing selective termination until the third trimester seems to improve survival, whereas immediate selective termination reduces the risk of preterm delivery. Furthermore, deferred selective termination requires an expert center capable of performing the selective termination procedure on an emergency basis if required.

Predictive value of maternal serum placental growth factor levels for discordant fetal growth in twins: a retrospective cohort study.

BACKGROUND: Accurate prenatal recognition of discordant fetal growth in twins is critical for deciding suitable management strategies. We explored the predictive value of the level of maternal second-trimester placental growth factor (PLGF) as a novel indicator of discordant fetal growth. METHODS: A total of 860 women pregnant with twins were enrolled, including 168 women with monochorionic twins (31 cases of discordant fetal growth and 137 without) and 692 with dichorionic twins (79 cases of discordant fetal growth and 613 without). Maternal second-trimester PLGF concentrations were measured via immunofluorescence. RESULTS: Maternal second-trimester PLGF levels were significantly lower in women pregnant with twins who subsequently developed discordant fetal growth than in those who did not (monochorionic twin pregnancy: P < 0.001; dichorionic twin pregnancy: P < 0.001). A 3-4 fold difference in median PLGF concentrations was detected between the two groups with both monochorionic and dichorionic twin pregnancies. Maternal second-trimester PLGF levels were significantly correlated with birth weight differences (monochorionic twin pregnancy: r = - 0.331, P < 0.001; dichorionic twin pregnancy: r = - 0.234, P < 0.001). A receiver operating characteristic curve was used to evaluate the predictive efficiency. In monochorionic twin pregnancies, the area under the curve (AUC) was 0.751 (95% confidence interval [CI]: 0.649-0.852), and the cutoff value was 187.5 pg/mL with a sensitivity of 77.4% and specificity of 71.0%. In dichorionic twin pregnancies, the AUC was 0.716 (95% CI; 0.655-0.777), and the cutoff value was 252.5 pg/mL with a sensitivity of 65.1% and specificity of 69.6%. Based on the above cutoff values, univariate and multivariate logistic regression analyses were performed to calculate the odds ratios (OR) for the PLGF levels. After adjustment for potential confounding factors, low PLGF concentrations still significantly increased the risk of discordant fetal growth (monochorionic twin pregnancy: adjusted OR: 7.039, 95% CI: 2.798-17.710, P < 0.001; dichorionic twin pregnancy: adjusted OR: 4.279, 95% CI: 2.572-7.120, P < 0.001). CONCLUSIONS: A low maternal second-trimester PLGF level is considered a remarkable risk factor and potential predictor of discordant fetal growth. This finding provides a complementary screening strategy for the prediction of discordant fetal growth and offers a unique perspective for the subsequent research in this field.

Longitudinal maternal hemodynamic evaluation in uncomplicated twin pregnancies according to chorionicity: physiological cardiovascular dysfunction in monochorionic twin pregnancy.

OBJECTIVE: Maternal cardiac function plays a crucial role in placental function and development. The maternal hemodynamic changes in twin pregnancy are more pronounced than those in singleton pregnancy, presumably due to a greater plasma volume expansion. In view of the correlation between maternal cardiac and placental function, it is plausible that chorionicity could influence maternal cardiac function. The aim of this study was to compare the longitudinal maternal hemodynamic changes between uncomplicated dichorionic (DC) and monochorionic (MC) twin pregnancies and in comparison to singleton pregnancies. METHODS: Included in the study were 40 MC diamniotic and 35 DC diamniotic uncomplicated twin pregnancies. These were compared with a group of 294 healthy singleton pregnancies from a previous cross-sectional study. All participants underwent a hemodynamic evaluation using an Ultrasound Cardiac Output Monitor (USCOM®), at three different stages in pregnancy (11-15 weeks, 20-24 weeks and 29-33 weeks). The following parameters were recorded: mean arterial pressure (MAP), stroke volume (SV), stroke volume index (SVI), heart rate, cardiac output (CO), cardiac index (CI), systemic vascular resistance (SVR), systemic vascular resistance index (SVRI), stroke volume variation, Smith-Madigan inotropy index (INO) and potential-to-kinetic-energy ratio (PKR). RESULTS: In the first trimester, DC and MC twin pregnancies showed lower MAP, SVR and PKR and higher CO and SV in comparison to singleton pregnancy. In the second trimester, maternal CO (8.33 vs 7.30 L/min, P = 0.03) and CI (4.52 vs 4.00 L/min/m2 , P = 0.02) were significantly higher in MC compared with DC twin pregnancy. In the third trimester, compared with in singleton pregnancy, women with MC twin pregnancy showed significantly higher PKR (24.06 vs 20.13, P = 0.03) and SVRI (1837.20 vs 1698.48 dynes × s/cm5 /m2 , P = 0.03), and significantly lower SV (78.80 vs 88.80 mL, P = 0.01), SVI (42.79 vs 50.31 mL/m2 , P < 0.01) and INO (1.70 vs 1.87 W/m2 , P = 0.03); these differences were not observed between DC twin and singleton pregnancies. CONCLUSIONS: Maternal cardiovascular function undergoes significant change during uncomplicated twin pregnancy and chorionicity influences maternal hemodynamics. In both MC and DC twin pregnancy, hemodynamic changes are detectable as early as the first trimester, showing higher maternal CO and lower SVR compared with singleton pregnancy. In DC twin pregnancy, the maternal hemodynamics remain stable during the rest of pregnancy. In contrast, in MC twin pregnancy, the rise in maternal CO continues in the second trimester in order to sustain the greater placental growth. There is a subsequent crossover, with a reduction in cardiovascular performance during the third trimester. © 2023 International Society of Ultrasound in Obstetrics and Gynecology.

A Rare Dichorionic Triamniotic Triplet Pregnancy with Spontaneous Twin Anemia-Polycythemia Sequence between Two Dichorionic Fetuses.

INTRODUCTION: This report presents a rare case of spontaneous twin anemia-polycythemia sequence (TAPS) between two dichorionic fetuses in a spontaneous, homozygotic, dichorionic, triamniotic, triplet pregnancy treated with multiple intrauterine blood transfusions (IUTs) and partial exchange transfusions (PETs). CASE PRESENTATION: The pregnancy was diagnosed with stage IV TAPS at gestational week 25+1. The patient was treated with laser surgery combined with multiple IUTs and PETs. The triplets were delivered at a planned caesarean section at gestational week 28+1 with postnatal hemoglobin values of 18.21, 26.43, and 11.92 g/dL in triplet 1, 2, and 3, respectively. At 4 years of age, triplet 1 is considered healthy, triplet 2 is diagnosed with mild mental retardation, and triplet 3 with profound mental retardation and dystonic cerebral palsy. DISCUSSION: This is an extremely rare case of TAPS between dichorionic fetuses in a triplet pregnancy, and routine surveillance with measurement of middle cerebral artery peak systolic velocity in dichorionic pregnancies may contribute to the detection of similar cases in the future. Furthermore, this case contributes with rare long-term follow-up data of children treated for high-stage TAPS with multiple IUTs and PETs.

Enhanced elimination of betamethasone in dichorionic twin pregnancies.

AIM: No study has evaluated the betamethasone pharmacokinetics in twin pregnancies according to chorionicity. This study aimed to describe and compare the betamethasone pharmacokinetic parameters in singleton and dichorionic (DC) and monochorionic twin pregnancies in the third trimester of pregnancy. METHODS: Twenty-six pregnant women received 2 intramuscular doses of 6 mg of betamethasone sodium phosphate plus 6 mg betamethasone acetate due to preterm labour. Serial blood samples were collected for 24 hours after the first intramuscular dose of betamethasone esters. Betamethasone plasma concentrations were quantified using a validated liquid chromatography-tandem mass spectrometry analytical method, and the pharmacokinetic parameters were obtained employing a noncompartmental model. Preliminary data on the betamethasone placental transfer are also presented. RESULTS: The geometric mean (95% confidence interval) of AUC0-∞ 645.1 (504.3-825.2) vs. 409.8 (311.2-539.6) ng.h/mL and CL/F 17.70 (13.84-22.65) vs. 27.87 (21.17-36.69) were significantly different, respectively, in singleton pregnancies when compared to DC twins. CONCLUSION: Data from this study suggest that the presence of 2 foetoplacental units may increase the betamethasone metabolism by hepatic CYP3A4 and/or placental 11ß-HSD2 enzymes. Pharmacokinetic-pharmacodynamic clinical studies are needed to investigate whether these betamethasone pharmacokinetic changes have clinical repercussions for the newborns and require dose adjustment in DC twin pregnancies.

Perinatal outcome after selective termination in dichorionic twins discordant for congenital anomalies.

INTRODUCTION: Our objective was to evaluate the perinatal outcome of selective termination of dichorionic twin pregnancies with discordant anomalies, according to gestational age at time of procedure. MATERIAL AND METHODS: Retrospective review of 147 dichorionic twin pregnancies referred to our Fetal Medicine Unit between 2003 and 2018 for selective termination. Gestational age at delivery, fetal loss, and overall and 28-day post-delivery survival rates, were evaluated according to gestational age at time of procedure. Selective termination procedure was defined as early, intermediate, and late when performed before 18 weeks, between 18 and 23 weeks, and after 23 weeks, respectively. Kruskal-Wallis and chi-squared test were used to compare groups. RESULTS: Overall survival at 28 days post-delivery, pregnancy loss, and preterm delivery before 32 weeks of gestation rates were 93.4%, 6.9%, and 15.5%, respectively. When stratified by gestational age at procedure, intermediate selective termination was associated with a lower survival rate than early and late procedures (86% vs. 96.9% and 100%, respectively; p = 0.035), and a nonsignificant trend for higher pregnancy loss (12% vs. 3.1%). Preterm delivery before 32 weeks of gestation occurred in 27% of late procedures, which was significantly higher than in early (9.5%) and intermediate (18.2%) procedures. CONCLUSIONS: Selective termination in dichorionic twin pregnancies with discordant fetal anomaly is associated with low pregnancy loss and preterm delivery rate, primarily when performed before 18 weeks. When legally possible, late procedures can be a good alternative, particularly in those cases diagnosed beyond the 18th week of gestation.

Fetomaternal hemorrhage occurred in one fetus of dichorionic twin pregnancy.

In a twin pregnancy, it may be difficult to notice the decreased fetal movements, which is one of the main symptoms of fetomaternal hemorrhage, in one fetus due to the movements of the other fetus.

Elective Fetal Reduction in Dichorionic Diamniotic Twin Pregnancies on Parental Request: A Single-Centre Experience.

OBJECTIVES: Our study aimed to examine a subset of electively reduced twins and compare their outcomes with those of expectantly managed twins, along with a cohort of singleton pregnancies. The secondary aim was to ascertain the procedure-related miscarriage risks. METHODS: A retrospective cohort analysis was performed at Apollo Centre for Fetal Medicine, New Delhi, comparing pregnancy outcomes in dichorionic diamniotic twin pregnancies which were reduced to singletons (group 1) with that of women with dichorionic twins managed expectantly (group 0) and women with a singleton pregnancy (group 2). Comparison of continuous and categorical variables was conducted using standard statistical tests. RESULTS: We analysed 35 twins which were reduced to singletons, 421 expectantly managed dichorionic twins and 1915 women with a singleton pregnancy. In the reduction group, the rate of procedure related pregnancy loss<24 weeks was lower, compared to the expectantly managed twins, although the difference was not statistically significant (5.71% [2/35] vs. 7.13% [30/421]; p = 1.000). The median gestational age at delivery was significantly higher in reduced twins compared to expectantly managed twin pregnancies (38.0 vs. 35.4 weeks respectively, p < 0.001) with a higher mean birth weight at delivery, both of which were comparable to that among the singleton pregnancies (38.3 weeks). The rates of preterm birth <32 weeks and <34 weeks in the expectantly managed twins were significantly higher at 19.8% (66/334) and 25.7% (86/334) compared to the reduced twins, all of whom delivered beyond 34 weeks. The rates of preterm births <32 weeks, <34 weeks, and the late preterm births in the reduced twins were comparable to those in the singleton cohort. CONCLUSIONS: The obstetric and perinatal outcomes after reduction of a dichorionic twin are better than an expectantly managed twin without an associated increase in pregnancy loss rates. Fetal reduction of dichorionic twin to a singleton appears to be a safe procedure in expert hands.

Factors associated with the development of spontaneous intertwin membrane separation in dichorionic twin pregnancy.

OBJECTIVE: We examined factors associated with the development of spontaneous intertwin membrane separation in dichorionic twin pregnancy. METHODS: Medical charts of 618 dichorionic twin pregnancies without the history of amniocentesis managed after 22 weeks' gestation at Japanese Red Cross Katsushika Maternity Hospital between 2002 and 2017 were reviewed. RESULTS: Twenty-four cases (3.9%) were diagnosed with spontaneous intertwine membrane separation. The presence of different fetal sex and separated placentae were associated with the development of spontaneous intertwin membrane separation in dichorionic twin pregnancy (different fetal sex: crude odds ratio 2.44, 95% confidence interval, 1.1-5.5, p = .03; separated placentae: crude odds ratio 4.14, 95% confidence interval, 1.3-13, p = .01). CONCLUSION: The development of spontaneous intertwin membrane separation in dichorionic twin pregnancies seemed to be associated with dizygotic.

Is it worth reducing twins to singletons after IVF-ET? A retrospective cohort study using propensity score matching.

INTRODUCTION: Many studies have shown that multifetal reduction of high-order multiple pregnancies results in improved pregnancy outcomes. However, whether conducting elective fetal reduction from dichorionic twins after in vitro fertilization (IVF) is worthwhile remains controversial. This study aimed to determine whether elective fetal reduction of dichorionic twins after IVF and embryo transfer (IVF-ET) is associated with increased take-home baby rate. MATERIAL AND METHODS: This was a retrospective cohort study of 3600 dichorionic twin pregnancies after IVF-ET. The reduced group included 71 women with transvaginal elective fetal reduction between 7 and 8 weeks of gestation. The control group (n = 3529) comprised women who were managed expectantly. Propensity score matching was conducted before pregnancy outcomes were compared. RESULTS: The take-home baby rate was significantly lower in the reduced group (83.1% vs 92.8%, P = 0.004). The total miscarriage rate was significantly higher in the reduced group (12.7% vs 6.2%, P = 0.04). Although preterm delivery rate was lower in the reduced group (P < 0.001), over 90% were over 32 weeks, whereas the proportions were equal in the reduced group. CONCLUSIONS: In dichorionic twin pregnancies after IVF-ET, elective fetal reduction to singleton significantly decreased the chance of taking home live babies.

Maternal and neonatal outcomes in dichorionic twin pregnancies following IVF treatment: a hospital-based comparative study.

AIM: To compare maternal, and neonatal outcomes in IVF/ICSI and spontaneously conceived dichorionic twin pregnancy. METHOD: We collected data regarding dichorionic twin pregnancies following in vitro fertilization/ intracytoplasmic sperm injection (IVF/ICSI, n=162) with the transfer of fresh embryos as well as data regarding spontaneously conceived pregnancies (n=213) delivered after 28 weeks of gestation at the Department of Obstetrics and Gynecology, Renmin Hospital in Wuhan in the years of 2010-2013. We then compared maternal and neonatal outcomes between IVF/ICSI and spontaneous dichorionic twin pregnancies, with a subgroup analysis separating traditional IVF from ICSI pregnancies. Odds ratios (OR) for associations between IVF/ICSI and pregnancy outcomes were adjusted for maternal factors. RESULTS: The mean maternal age and the percentage of primiparous women were significantly higher in the IVF/ICSI group. Multivariate analysis revealed that maternal outcomes were comparable in both groups with/without adjustment for maternal age and parity. However, IVF/ICSI twins were less likely to have birth weight discordance than those spontaneously conceived (unadjusted OR=0.526, 95% CI 0.297-0.932; adjusted OR=0.486, 95% CI 0.255-0.856). In subgroup analyses, these associations were confirmed in the IVF (adjusted OR=0.496, 95% CI 0.265-0.926), but not in the ICSI group (adjusted OR=0.500, 95% CI 0.139-1.807). CONCLUSION: IVF/ICSI treatment was not a risk factor for adverse maternal neonatal outcomes, but the risk for birth weight discordance is lower among IVF/ICSI twins.

[Perinatal outcome of monochorionic and dichorionic twin gestations: a study of 775 pregnancies at Reunion Island]. / Morbidité et mortalité périnatale des jumeaux et influence de la chorionicité: expérience de 10ans dans le Sud-Réunion. Étude de 775 grossesses.

OBJECTIVES: To compare the perinatal mortality and morbidity of infants born from monochorionic versus dichorionic twin pregnancies (TP). PATIENTS AND METHODS: Retrospective, comparative study of monochorionic and dichorionic TP over 10 years in the south of Reunion Island. Information regarding demographic, gestational and perinatal variables of mothers and infants was collected from the hospital perinatal database. RESULTS: Six hundred and twenty dichorionic and 155 monochorionic TP were analyzed. In case of monochorionic TP, mothers had higher rates of pregnancy-related hypertension (OR=1.82, 95%CI=[1.02-3.29] ; P=0.03) and hospitalization (OR=1.48, 95%CI=[1.02-2.16]; P=0.03). Newborns from monochorionic TP had higher morbidity for : very preterm birth (birth before 33 weeks gestation) (OR=1.65, 95%CI=[1.02-2.66]; P=0.02), very low birth weight (birth weight<1500g) (OR=1.73, 95%CI=[1.57-3.13]; P<0.001), Apgar<7 at 1 minute (OR=1.76, 95%CI=[1.18-2.61]; P<0.01) and hospitalization (OR=2.08, 95%CI=[1.58-2.73]; P<0.001). Perinatal mortality was also significantly higher (OR=2.47, 95%CI=[1.54-3.94]; P<0.001), as well intrauterine fetal death (OR=3.96, 95%CI=[1.95-8.05]; P<0.001) CONCLUSION: This study confirms that few differences exist among dichorionic and monochorionic TP with regard to maternal morbidity, while neonatal morbidity and mortality are higher in twins born from monochorionic pregnancies.