Neonatal respiratory complications in twins at 36-38 weeks of gestation.

BACKGROUND: Twin pregnancies are associated with a high risk of perinatal mortality and morbidity. Late preterm or early term delivery is frequently performed to avoid unexpected fetal death in uncomplicated twin pregnancies. Nonetheless, delivery before full term is associated with neonatal respiratory complications. This study aimed to evaluate perinatal respiratory complications in twins delivered between 36 and 38 weeks of gestation. METHODS: A retrospective cohort study was conducted on twins delivered between 36 and 38 weeks of gestation from January 2008 to June 2020. The primary outcomes were the incidence of composite neonatal respiratory morbidity, which included respiratory distress syndrome, transient tachypnea of the newborn, meconium aspiration syndrome, mechanical ventilation or continuous positive airway pressure according to gestational age at delivery, and chorionicity. The relationship between gestational age at delivery and composite neonatal respiratory morbidity was evaluated using multivariate logistic regression analysis adjusted for potential confounders. RESULTS: This study included 1608 twins (614 monochorionic diamniotic twins, 994 dichorionic diamniotic twins). At 36, 37, and 38 weeks of gestation, the frequencies of composite neonatal respiratory morbidity were 19.4%, 10.7%, and 9.2% in dichorionic diamniotic twins and 13.6%, 8.7%, and 9.4% in monochorionic diamniotic twins, respectively. In dichorionic diamniotic twins, the composite neonatal respiratory morbidity rate was higher for twins delivered at 36 weeks of gestation than for those delivered at 37 weeks. No significant differences between monochorionic diamniotic twins were detected. CONCLUSIONS: In uncomplicated dichorionic diamniotic twin pregnancies, delivery should be considered after 37 weeks of gestation to reduce neonatal respiratory complications.

Pregnancy outcomes of cerclage in twin gestations: a multicenter retrospective cohort study.

OBJECTIVES: To determine the effects of cerclage on twin pregnancies. METHODS: A multicenter, retrospective, cohort study was conducted at 10 tertiary centers using a web-based data collection platform. The study population included twin pregnancies delivered after 20 weeks of gestation. Patients with one or two fetal deaths before 20 weeks of gestation were excluded. Maternal characteristics, including prenatal cervical length (CL) and obstetric outcomes, were retrieved from the electronic medical records. RESULTS: A total of 1,473 patients had available data regarding the CL measured before 24 weeks of gestation. Seven patients without CL data obtained prior to cerclage were excluded from the analysis. The study population was divided into two groups according to the CL measured during the mid-trimester: the CL ≤2.5 cm group (n = 127) and the CL >2.5 cm group (n = 1,339). A total of 127 patients (8.7%) were included in the CL ≤2.5 cm group, including 41.7% (53/127) who received cerclage. Patients in the CL >2.5 cm group who received cerclage had significantly lower gestational age at delivery than the control group (hazard ratio (HR): 1.8; 95% confidence interval (CI): 1.11-2.87; p = .016). Patients in the CL ≤2.5 cm group who received cerclage had a significantly higher gestational age at delivery than the control group (HR: 0.5; 95% CI: 0.30-0.82; p value = .006). CONCLUSIONS: In twin pregnancies with a CL ≤2.5 cm, cerclage significantly prolongs gestation. However, unnecessary cerclage in women with a CL >2.5 cm may result in a higher risk of preterm labor and histologic chorioamnionitis although this study has a limitation originated from retrospective design.

Risk Factors for Postpartum Hemorrhage in Severe Pre-Eclampsia: A Retrospective Single-Centre Study of 1953 Cases.

BACKGROUND Severe pre-eclampsia (sPE) and postpartum hemorrhage (PPH) in pregnancy have serious impact on maternal and fetal health and life. Co-occurrence of sPE and PPH often leads to poor pregnancy outcomes. We explored risk factors associated with PPH in women with sPE. MATERIAL AND METHODS This retrospective study included 1953 women with sPE who delivered at the Women's Hospital of Nanjing Medical University between April 2015 and April 2023. Risk factors for developing PPH in sPE were analyzed, and subgroups were analyzed by delivery mode (cesarean and vaginal). RESULTS A total of 197 women with PPH and 1756 women without PPH were included. Binary logistic regression results showed twin pregnancy (P<0.001), placenta accreta spectrum disorders (P=0.045), and placenta previa (P<0.001) were independent risk factors for PPH in women with sPE. Subgroup analysis showed risk factors for PPH in cesarean delivery group were the same as in the total population, but vaginal delivery did not reduce risk of PPH. Spinal anesthesia reduced risk of PPH relative to general anesthesia (P=0.034). Vaginal delivery group had no independent risk factors for PPH; however, magnesium sulfate (P=0.041) reduced PPH incidence. CONCLUSIONS Women with twin pregnancy, placenta accreta spectrum disorders, placenta previa, and assisted reproduction with sPE should be alerted to the risk of PPH, and spinal anesthesia should be preferred in cesarean delivery. Magnesium sulfate should be used aggressively in women with sPE; however, the relationship between magnesium sulfate and PPH risk needs further investigation.

Changes in cytokine and sequestosome-1 levels during twin pregnancy progression: Association with outcome.

BACKGROUND: Twin pregnancies are associated with complications and adverse outcomes. The number of twin pregnancies has increased in the last decades, due to the use of assisted reproductive techniques and delayed childbearing. Analysis of changes that occur during twin pregnancy progression and their association with outcome will lead to improved clinical interventions. OBJECTIVE: We evaluated if the plasma concentration of select cytokines and the level of sequestosome-1 (p62) in peripheral blood mononuclear cells (PBMCs) during each trimester of twin gestations was predictive of pregnancy outcome. STUDY DESIGN: This prospective, observational study was conducted at Careggi University Hospital, Florence, Italy. Plasma from 82 women with twin pregnancies was collected in each trimester for measurement of interleukin (IL)-1ß, IL-6, IL-10, IL-12 and tumor necrosis factor (TNF)-α. The intracellular PBMC concentration of p62, a protein involved in autophagy, kinase activity and cell differentiation, was also determined. RESULTS: IL-1ß (p < 0.001), IL-6 (p < 0.001), TNF-α (p < 0.001) and p62 (p < 0.05) increased from the 1st to the 2nd to the 3rd trimester. The TNF-α level was correlated with the IL-1ß concentration in the 1st and 3rd trimesters p < 0.01) and with the IL-6 concentration in each of the three trimesters (p < 0.01). The intracellular p62 level in PBMCs was negatively correlated with the concentration of IL-1ß in the 2nd trimester (p < 0.05) and negatively correlated with the IL-6 level in the 3rd trimester (p < 0.05). The TNF-α level was significantly higher in the 2nd (p < 0.05) and 3rd (p < 0.001) trimester in women with a spontaneous preterm delivery. The TNF-α concentrations in the 2nd (p < 0.05) and 3rd (p < 0.01) trimester, respectively, and 3rd trimester IL-6 (p < 0.01), were negatively associated with gestational age at delivery. The concentration of IL-6 was highest in the 2nd (p < 0.05) and 3rd (p < 0.05) trimesters in women who utilized assisted reproductive technologies. An elevated IL-1ß level in the 3rd trimester was associated with gestational diabetes mellitus (p < 0.05). CONCLUSION: Variations in cytokine levels between individual women during the three trimesters of twin gestations are predictive of spontaneous preterm delivery and the onset of gestational diabetes.

Prognosis of remaining fetus in twin pregnancy after demise of one fetus according to its location.

BACKGROUND: To investigate the prognosis of the remaining fetus in twin pregnancy after experiencing one fetal demise in the first trimester according to the location of the demised fetus. METHODS: This was a retrospective study of twin pregnancies with one fetal demise after the first trimester (14 weeks of gestation) delivered between September 2004 and September 2022. The study population was divided into two groups based on the location of the demised fetus as determined by the last recorded ultrasonography results: Group 1 included twin pregnancies where the presenting fetus was demised (n = 36) and Group 2 included twin pregnancies where the non-presenting fetus was demised (n = 44). The obstetric and neonatal outcomes were also reviewed. RESULTS: A total of 80 pregnant women were included. The median gestational age for the diagnosis of fetal demise was 24.1 weeks. The gestational age of the demised fetus was not different between Groups 1 and 2; however, the gestational age of the remaining fetus at delivery was significantly earlier in Group 1 than it was in Group 2 (33.8 vs. 37.3 weeks, P = .004). The rate of preterm birth before 28 weeks was almost five times higher in Group 1 than in Group 2 (22.2% vs. 4.5%, P = .037). Regression analysis demonstrated significant differences between Groups 1 and 2. Respiratory distress syndrome, bronchopulmonary dysplasia, patent ductus arteriosus, retinopathy of prematurity, and jaundice were more common in Group 1 than in Group 2; however, the association was not significant after adjusting for gestational age at delivery. CONCLUSIONS: When the presenting fetus is demised in a twin pregnancy, the remaining fetus tends to be delivered earlier than when the non-presenting fetus is demised.

Dichorionic diamniotic twin pregnancy after preimplantation genetic testing and single blastocyst transfer.

BACKGROUND: In addition to the potential for multiple pregnancies, natural conception occurring in preimplantation genetic testing (PGT) increases undesired genetic risk. Some studies showed that a dichorionic diamniotic twin pregnancy after a single blastocyst transfer could be caused by embryo splitting or concurrent spontaneous conception. CASE: We describe a patient undergoing PGT who had a dichorionic diamniotic twin pregnancy after single blastocyst transfer in a natural cycle. In this case, we recommended to determine genetic status of the twins by prenatal diagnosis. The results showed that karyotype, chromosome copy number variation, and parental ACAT1 variation of the twins were all normal and similar. To investigate the origin of pregnancy, we used the genotype data of single-nucleotide polymorphisms typical of genome-wide association studies. Dizygotic twins were inferred by robust estimation of kinship coefficients, which confirmed the occurrence of a spontaneous conception. CONCLUSIONS: This case strengthens the importance of genetic counseling to inform couples with reproductive genetic risk, such as those who undergo PGT, that intercourse should be avoided, especially in natural transfer cycles. Moreover, prenatal diagnosis remains essential and is strongly recommended to avoid genetic risks.

Cesarean section prior to 28 weeks' gestation: which type of uterine incision is optimal?

OBJECTIVE: The purpose of this study was to determine the factors that influence physician preference for type of hysterotomy incisions in gravidas with a singleton or twin pregnancy undergoing cesarean section under 28 weeks, and to assess factors that result in delivery complications, defined as either intraoperative dystocia or hysterotomy extension. We hypothesized that compared to those with non-cephalic presentations, gravidas with a presenting fetus in cephalic presentation would have higher rates of low-transverse cesarean section, and reduced rates of delivery complications with low-transverse hysterotomy. METHODS: This was a retrospective cohort chart analysis of 128 gravidas between 23 0/7 and 27 6/7 weeks undergoing cesarean section at a single academic institution between August 2010 and December 2022. Data was abstracted for factors that might influence the decision for hysterotomy incision type, as well as for documentation of difficulty with delivery of the fetus or need for hysterotomy extension to affect delivery. RESULTS: There was a total of 128 subjects, 113 with a singleton gestation and 15 with twins. The presenting fetus was in cephalic presentation in 43 (33.6%), breech presentation in 71 (55.5%), transverse/oblique lie in 13 (10.2%), and not documented in 1 (0.8%). Sixty-eight (53.1%) had a low-transverse cesarean section (LTCS), 53 (41.4%) had a Classical, 5 (3.9%) had a low-vertical hysterotomy and 2 (1.6%) had a mid-transverse incision. There was a significantly higher rate of LTCS among gravidas with the presenting fetus in cephalic presentation (30/43, 69.8%) compared to those with breech (31/71, 43.7%) or transverse/oblique presentations (7/13, 53.8%), p = .03. No other significant associations were related to hysterotomy incision, including nulliparity, racially or ethnically minoritized status, plurality, indication for cesarean delivery, or pre-cesarean labor. Twenty (15.6%) subjects experienced either an intraoperative dystocia or hysterotomy extension. For the entire cohort, there was a greater median cervical dilatation in those with delivery complications (4.0 cm, IQR .5 - 10 cm) compared to those without complications (1.5, IQR 0 - 4.0), p = .03, but no significant association between delivery complications and fetal presentation, hysterotomy type, plurality, or other demographic/obstetrical factors. However, among gravidas undergoing low-transverse cesarean section, only 2/30 (6.7%) with cephalic presentations had a delivery complication, compared to 9/31 (29.0%) with breech presentations and 3/7 (42.9%) with a transverse/oblique lie, p = .03. CONCLUSION: In pregnancies under 28 weeks, the performance of a low-transverse cesarean section was significantly associated only with presentation of the presenting fetus. Among those with cephalic presentations, the rate of intrapartum dystocia or hysterotomy extension was low after a low-transverse hysterotomy, suggesting that in this subgroup, a low-transverse cesarean section should be considered.

Longitudinal hematological change in uncomplicated twin pregnancies: The white blood cell count decreases through pregnancy after the first trimester.

OBJECTIVE: Longitudinal hematological changes throughout twin pregnancies have not been reported. This study aimed to reveal longitudinal changes in hematological indices in twin pregnancies. MATERIALS AND METHODS: We conducted a retrospective chart review of hematological changes in uncomplicated twin pregnancies delivered at ≥37 weeks of gestation between 2010 and 2013 and randomly selected uncomplicated singletons during the same period. A complete blood count and hemogram were performed as blood examinations in the first trimester (9-13 weeks), late second trimester (22-27 weeks), mid-third trimester (33-35 weeks, only in twin pregnancies), and late third trimester (36-38 weeks). We evaluated inter-trimester differences in hematological indices and compared the values between twin and singleton pregnancies in each trimester. RESULTS: The final analysis group included 60 twin pregnancies and 63 singleton pregnancies. The white blood cell (WBC) count in twin pregnancies decreased throughout the pregnancy after the first trimester and became significantly lower than that in singletons in the late third trimester. The WBC count showed only a slight decrease in the third trimester in singleton pregnancies, whereas it showed a marked decrease throughout the pregnancy in twin pregnancies. The marked decrease in the total WBC count in twin pregnancies is mainly due to a decrease in neutrophils. The red blood cell count and hemoglobin and hematocrit values in twin pregnancies showed more marked decreases in the second trimester than in singletons. No decrease was observed after the second trimester of pregnancy. The platelet count decreased in the third trimester of twin pregnancies. CONCLUSION: We clarified the longitudinal hematological changes in twin pregnancies that showed augmentation of or differed from those of singleton pregnancies. It should be specifically mentioned that the WBC count markedly decreased through pregnancy after the first trimester, which is a characteristic change in twin pregnancies.

Pregnancy outcomes of monochorionic diamniotic and dichorionic diamniotic twin pregnancies conceived by assisted reproductive technology and conceived naturally: a study based on chorionic comparison.

OBJECTIVE: To evaluate monochorionic diamniotic (MCDA) and dichorionic diamniotic (DCDA) twin pregnancies conceived by assisted reproductive technology (ART) and conceived naturally. METHODS: We retrospectively analyzed the data on twin pregnancies conceived by ART from January 2015 to January 2022,and compared pregnancy outcomes of MCDA and DCDA twins conceived by ART with those of MCDA and DCDA twins conceived naturally, pregnancy outcomes between MCDA and DCDA twins conceived by ART, and pregnancy outcomes of DCT and TCT pregnancies reduced to DCDA pregnancies with those of DCDA pregnancies conceived naturally. RESULT: MCDA pregnancies conceived by ART accounted for 4.21% of the total pregnancies conceived by ART and 43.81% of the total MCDA pregnancies. DCDA pregnancies conceived by ART accounted for 95.79% of the total pregnancies conceived by ART and 93.26% of the total DCDA pregnancies. Women with MCDA pregnancies conceived by ART had a higher premature delivery rate, lower neonatal weights, a higher placenta previa rate, and a lower twin survival rate than those with MCDA pregnancies conceived naturally (all p < 0.05). Women with DCDA pregnancies conceived naturally had lower rates of preterm birth, higher neonatal weights, and higher twin survival rates than women with DCDA pregnancies conceived by ART and those with DCT and TCT pregnancies reduced to DCDA pregnancies (all p < 0.05). CONCLUSION: Our study confirms that the pregnancy outcomes of MCDA pregnancies conceived by ART are worse than those of MCDA pregnancies conceived naturally. Similarly, the pregnancy outcomes of naturally-conceived DCDA pregnancies are better than those of DCDA pregnancies conceived by ART and DCT and TCT pregnancies reduced to DCDA pregnancies.

Pregnancy Outcomes and Obstetrical Complications of Twin Pregnancies with Endometriosis: A Single-Center Cohort Study.

PURPOSE: There are many studies regarding the increased relationship between pregnancy outcomes of singleton with endometriosis. However, there was limited evidence of twin pregnancies with endometriosis. This study aimed to compare the pregnancy outcomes and complications in twin pregnancies with or without endometriosis in a single institution. MATERIALS AND METHODS: From January 2011 to July 2022, a retrospective analysis of twin pregnancies was conducted. The endometriosis group included patient with histological or visual confirmation before pregnancy or during cesarean section. Pregnancy outcomes and complications were compared between the two groups. RESULTS: Out of 1714 patients examined, 127 (7.4%) were included in the endometriosis group. Maternal body mass index (BMI) was lower in the endometriosis group (p<0.001). There were no significant differences in maternal age, mode of conception, chorionicity, and pregnancy outcomes, such as gestational age at delivery (p=0.835) and the preterm birth rate (p=0.579). The endometriosis group had a significantly higher rate of obstetrical complication: small for gestational age (SGA) <10% (p=0.029). However, after adjustment for BMI, the endometriosis group showed no statistical significance in obstetrical complications, including SGA (adjusted odds ratio, 1.568; 95% confidence interval, 0.984-2.499; p=0.059). CONCLUSION: Twin pregnancies with endometriosis were not related to adverse effects on pregnancy outcomes and obstetrical complications. To confirm these outcomes, further large prospective studies are required.

Abnormal maternal apolipoprotein levels during pregnancy are risk factors for preterm birth in women with dichorionic twin pregnancies: A retrospective study.

OBJECTIVE: In singleton-pregnant women, abnormal maternal apolipoprotein levels have been confirmed as a risk factor for preterm birth. However, there are currently no studies on the relationship of the related research in twin-pregnant women. METHODS: This single-center retrospective study included 743 dichorionic twin-pregnant women who delivered between January 2019 and December 2020. Twins delivered before 37 weeks gestation were categorized as the preterm group, while those delivered at or after 37 weeks gestation were classified as the term group. Maternal serum apolipoprotein A1 (ApoA1) levels, apolipoprotein B (ApoB) levels, and the ApoB/ApoA1 ratio were measured in the first trimester(6-14 weeks), the second trimester(18-28 weeks) and the third trimester(after 28 weeks). We conducted SPSS analysis to evaluate the correlation between ApoA1 levels, ApoB levels, the ApoB/ApoA1 ratio and preterm birth. RESULTS: Among the 743 included dichorionic twin-pregnant women, 53.57 % (398/743) delivered preterm. Compared with the term group, the ApoA1 levels in the third trimester were lower (p < 0.001), while the Apo B/ApoA1 ratio was higher in the second (p = 0.01) and third trimesters in the preterm group (p = 0.001). When preterm birth was categorized as iatrogenic and spontaneous preterm birth, the results were similar. In the analysis stratified by prepregnancy BMI, a higher risk of preterm birth was associated with low ApoA1 levels and a high Apo B/ApoA1 ratio in the second and third trimesters only among the subgroup of overweight/obese dichorionic twin-pregnant women. CONCLUSIONS: Low ApoA1 levels and a high Apo B/ApoA1 ratio during the second and third trimesters were associated with a high incidence of preterm birth for overweight/obese dichorionic twin-pregnant women.

Maternal and fetal outcomes after planned cesarean or vaginal delivery in twin pregnancy: a comparison between 2 third level birth centers.

BACKGROUND: Twin pregnancy is associated with higher risks of adverse perinatal outcomes for both the mother and the babies. Among the many challenges in the follow-up of twin pregnancies, the mode of delivery is the last but not the least decision to be made, with the main influencing factors being amnionicity and fetal presentation. The aim of the study was to compare perinatal outcomes in two European centers using different protocols for twin birth in case of non-cephalic second twin; the Italian patients being delivered mainly by cesarean section with those in Belgium being routinely offered the choice of vaginal delivery (VD). METHODS: This was a dual center international retrospective observational study. The population included 843 women with a twin pregnancy ≥ 32 weeks (dichorionic or monochorionic diamniotic pregnancies) and a known pregnancy outcome. The population was stratified according to chorionicity. Demographic and pregnancy data were reported per pregnancy, whereas neonatal outcomes were reported per fetus. We used multiple logistic regression models to adjust for possible confounding variables and to compute the adjusted odds ratio (adjOR) for each maternal or neonatal outcome. RESULTS: The observed rate of cesarean delivery was significantly higher in the Italian cohort: 85% for dichorionic pregnancies and 94.4% for the monochorionic vs 45.2% and 54.4% respectively in the Belgian center (p-value < 0.001). We found that Belgian cohort showed significantly higher rates of NICU admission, respiratory distress at birth and Apgar score of < 7 after 5 min. Despite these differences, the composite severe adverse outcome was similar between the two groups. CONCLUSION: In this study, neither the presentation of the second twin nor the chorionicity affected maternal and severe neonatal outcomes, regardless of the mode of delivery in two tertiary care centers, but VD was associated to a poorer short-term neonatal outcome.

Vaccination in twin pregnancies: comparison between immunization before conception and during pregnancy.

To evaluate the development of neutralizing Anti-Spike Protein IgG (Anti-S-IgG) during twin pregnancies before conception vs. during pregnancy. In this prospective study, three blood samples were collected from pregnant women and subjected to anti-S-IgG immunodiagnostics. The patient's medical records, including vaccination and PCR test results, were collected from the hospital's electronic database. Age-matched non-pregnant women were used as a control group. We enrolled 83 women with twin pregnancies. 49 women were vaccinated before conception, 21 women were vaccinated during pregnancy, and 13 were not vaccinated. Of the 13 women who weren't vaccinated, three became positive during pregnancy, and all three were severely ill. By contrast, in women who were vaccinated during or before pregnancy, COVID-19 infection during pregnancy caused only mild symptoms. A ten-fold lower level of neutralizing Anti-S-IgG in the 3rd trimester was observed in healthy women who were vaccinated before conception and remained healthy until discharge from the hospital after delivery 1605 (IQR: 763-2410) compared to the healthy women who were vaccinated during pregnancy 152 AU/mL (IQR: 54-360). This difference was higher among women who were infected by COVID-19 (as verified by a positive PCR test). The third-trimester level of neutralizing Ant-S-IgG in the infected group was 4770 AU/mL (4760-6100) in infected women vaccinated before conception compared to those vaccinated during pregnancy who had 70 AU/mL (IQR: 20-170) (p < 0.001). In women vaccinated at 13-16 weeks gestation, neutralizing Anti-S-IgG at 20-22 weeks went up to 372 AU/mL (IQR: 120-1598) but rapidly dropped to 112 AU/mL (IQR: 54-357) at 28-30 weeks, (p < 0.001), a faster decline than in women vaccinated at a median 22 weeks before conception. Being infected by COVID-19 before conception was linked to having low Anti-S-IgG levels during pregnancy, whereas being infected by COVID-19 during pregnancy led to a very high response in the 3rd trimester. In twin pregnancies, significantly lower neutralizing Anti-S-IgG levels were observed in women vaccinated during pregnancy compared to those vaccinated before conception, whether infected or not infected by COVID-19. A full course of vaccination before conception is recommended.Trial registration. ClinicalTrials.gov Protocol Registration and Results System (PRS) Receipt Release Date: October 4, 2021. https://clinicaltrials.gov/ ID: NCT04595214.

Magnetic resonance imaging of intracranial anomalies in pregnancies complicated by twin anemia-polycythemia sequence.

PURPOSE: To describe fetal brain Magnetic Resonance Imaging (MRI) findings in a large series of monochorionic (MC) pregnancies complicated by Twin Anemia-Polycythemia Sequence (TAPS) prenatally diagnosed, so to characterize the potential intracranial complications associated with this condition, their frequency and potential treatment options. METHODS: This is a retrospective study of MC twin pregnancies complicated by TAPS and undergone fetal MRI in a single institution from 2006 to 2023. MRI control was performed and post-natal ultrasound (US) or MRI were available. RESULTS: 1250 MC pregnancies were evaluated in our institution. 50 pregnancies (4%) were diagnosed with TAPS, 29 underwent a fetal brain MRI. 13/29 pregnancies (44.8%) demonstrated brain findings at MRI in at least a twin. Neuroradiological findings were detected in 14/57 twins (24.6%). We detected four main categories of findings: hemorrhagic lesions, T2-weighted white-matter hyperintensities (WMH), brain edema-swelling and venous congestion. Nineteen findings were present in the anemic and three in the polycythemic twins, with a statistically significant ratio between the two groups (p-value = 0.01). Intrauterine MRI follow-up demonstrated the sequalae of hemorrhagic lesions. A complete regression of brain swelling, veins prominence and T2-WMHs was demonstrated after treatment. Postnatal imaging confirmed prenatal features. CONCLUSIONS: Our work demonstrates that TAPS-related MRI anomalies consisted in edematous/hemorrhagic lesions that occur mostly in anemic rather than in polycythemic twins. Fetoscopic laser surgery could have a potential decongestant role. Therefore, prenatal MRI may help in counselling and management in TAPS pregnancies, especially for the planning of therapy and the monitoring of its efficacy.

First-trimester serum biomarkers in twin pregnancies and adverse obstetric outcomes-a single center cohort study.

PURPOSE: This study aimed to determine the association of first-trimester maternal serum biomarkers with preterm birth (PTB), fetal growth restriction (FGR) and hypertensive disorders of pregnancy (HDP) in twin pregnancies. METHODS: This is a retrospective cohort study of twin pregnancies followed at Maternidade Dr. Alfredo da Costa, Lisbon, Portugal, between January 2010 and December 2022. We included women who completed first-trimester screening in our unit and had ongoing pregnancies with two live fetuses, and delivered after 24 weeks. Maternal characteristics, pregnancy-associated plasma protein-A (PAPP-A) and ß-human chorionic gonadotropin (ß-hCG) levels were analyzed for different outcomes: small for gestational age (SGA), gestational hypertension (GH), early and late-onset pre-eclampsia (PE), as well as the composite outcome of PTB associated with FGR and/or HDP. Univariable, multivariable logistic regression analyses and receiver-operating characteristic curve were used. RESULTS: 466 twin pregnancies met the inclusion criteria. Overall, 185 (39.7%) pregnancies were affected by SGA < 5th percentile and/or HDP. PAPP-A demonstrated a linear association with gestational age at birth and mean birth weight. PAPP-A proved to be an independent risk factor for SGA and PTB (< 34 and < 36 weeks) related to FGR and/or HDP. None of the women with PAPP-A MoM > 90th percentile developed early-onset PE or PTB < 34 weeks. CONCLUSION: A high serum PAPP-A (> 90th percentile) ruled out early-onset PE and PTB < 34 weeks. Unless other major risk factors for hypertensive disorders are present, these women should not be considered candidates for aspirin prophylaxis. Nevertheless, close monitoring of all TwP for adverse obstetric outcomes is still recommended.

Cervical elastography using E-Cervix™ for prediction of preterm birth in twin pregnancies with threatened preterm labor.

OBJECTIVE: To evaluate the prediction performance of E-Cervix™ for preterm birth in twin pregnancies with threatened preterm labor. METHODS: This was a single-center retrospective cohort study of twin pregnancies presenting to obstetrics triage for threatened preterm labor (PTL) between 23 0/7 - 33 6/7 weeks who received screening for PTL with transvaginal ultrasound cervical length (TVU CL) and cervical elastography with E-Cervix™ at the time of triage. Cervical elastography parameters were examined and compared between women who delivered preterm and those who did not. The quantification of cervical strain was calculated by a data analysis system that directly analyzes raw data from the region of interest (ROI) and described as hardness ratio (HR), mean strain level within 1 cm from internal (IOS) and external (EOS) os. RESULTS: 63 twin gestations without prior preterm birth and with threatened PTL between 23 0/7 - 33 6/7 weeks of gestation were included in the study. 27 (42.9 %) had cervical length < 25 mm, and were admitted for true PLT. Out of the 36 women with cervical length ≥ 25 mm, 6 (16.7 %) were admitted. Women with threatened PTL had significantly higher HR compared to those with true PTL (p < 0.01), and significantly lower IOS and EOS. Women who delivered preterm had significantly higher HR compared to those who did not delivery preterm and significantly lower IOS and EOS, in overall cohort, and in the subset of women with true PTL. Incidences of HR < 50 % and < 35 % were statistically significantly higher in women who delivered preterm compared to those who did not (p < 0.01). CONCLUSION: Cervical elastography with E-Cervix™ may be useful for assessment of twin gestations presenting to obstetrics triage for threatened PTL.

Outcomes of dichorionic twin pregnancies with fused versus separate placentas.

PURPOSE: In a certain proportion of dichorionic twin pregnancies, the two placentas are fused. The clinical significance of this finding remains unclear. Our objective was to compare outcomes of dichorionic twin pregnancies with fused versus separate placentas as determined on first-trimester ultrasound. METHODS: Retrospective study of patients with dichorionic twins followed at a tertiary center between 2014 and 2022. The co-primary outcomes were fetal growth restriction and preeclampsia. Associations between fused placentas and the study outcomes were estimated using multivariable Poisson regression and were reported as adjusted relative risk (aRR) with a 95%-confidence interval (CI). RESULTS: Of the 328 eligible patients, 175 (53.4%) and 153 (46.6%) had fused and separate placentas, respectively. Compared with pregnancies with separate placentas, patients with fused placentas had a lower risk of preeclampsia [aRR 0.48 (95%-CI 0.24-0.97)] but a higher risk of fetal growth restriction [aRR 1.23 (95%-CI 1.02-1.48)] and admission to the neonatal intensive care unit [aRR 1.31 (95%-CI 1.01-1.71)]. In addition, pregnancies with fused placentas were more likely to have a total placental weight below the 10th percentile than those with separate placentas [aRR 1.93 (95%-CI 1.16-3.21)]. DISCUSSION: Dichorionic twin pregnancies with fused placentas have a lower risk of preeclampsia but are more likely to be complicated by fetal growth restriction, observations that may be attributed to the lower total placentas mass in pregnancies with fused compared with separate placentas. Fused placentas can be used as a potential biomarker for the prediction of pregnancy complications in dichorionic twin pregnancies.

Study protocol for two randomised controlled trials evaluating the effects of Cerclage in the reduction of extreme preterm birth and perinatal mortality in twin pregnancies with a short cervix or dilatation: the TWIN Cerclage studies.

INTRODUCTION: Twin pregnancies have a high risk of extreme preterm birth (PTB) at less than 28 weeks of gestation, which is associated with increased risk of neonatal morbidity and mortality. Currently there is a lack of effective treatments for women with a twin pregnancy and a short cervix or cervical dilatation. A possible effective surgical method to reduce extreme PTB in twin pregnancies with an asymptomatic short cervix or dilatation at midpregnancy is the placement of a vaginal cerclage. METHODS AND ANALYSIS: We designed two multicentre randomised trials involving eight hospitals in the Netherlands (sites in other countries may be added at a later date). Women older than 16 years with a twin pregnancy at <24 weeks of gestation and an asymptomatic short cervix of ≤25 mm or cervical dilatation will be randomly allocated (1:1) to both trials on vaginal cerclage and standard treatment according to the current Dutch Society of Obstetrics and Gynaecology guideline (no cerclage). Permuted blocks sized 2 and 4 will be used to minimise the risk of disbalance. The primary outcome measure is PTB of <28 weeks. Analyses will be by intention to treat. The first trial is to demonstrate a risk reduction from 25% to 10% in the short cervix group, for which 194 patients need to be recruited. The second trial is to demonstrate a risk reduction from 80% to 35% in the dilatation group and will recruit 44 women. A cost-effectiveness analysis will be performed from a societal perspective. ETHICS AND DISSEMINATION: This study has been approved by the Research Ethics Committees in the Netherlands on 3/30/2023. Participants will be required to sign an informed consent form. The results will be presented at conferences and published in a peer-reviewed journal. Participants will be informed about the results. TRIAL REGISTRATION NUMBER: ClinicalTrials.gov, NCT05968794.