Vanishing Twin Research Articles

Comparison of perinatal outcomes of vanishing twin and twin pregnancies conceived following assisted reproductive technology: A retrospective analysis

Abstract Objective: The purpose of this study was to compare the perinatal outcomes of vanishing twin (VT) pregnancies with twin pregnancies following assisted reproductive technology treatment (ART). Design: Retrospective analysis. Setting: Infertility unit of a university level hospital. Materials and methods: We included all the women with dichorionic diamniotic twin pregnancies conceived following ART from Jan 2010 to Dec 2014 in our unit. We matched the VT group and twin group for maternal age and body mass index. Results: A total of 63 vanishing twin and 135 twin pregnancies were followed up. The vanishing twin rate was 31.8%. The live birth rate at term was significantly higher in VT group compared to twin group (69.8% vs. 16.3%, P P P = 0.0006) were significantly lower in VT group as compared to twin group. Significantly higher number of babies were born with birth weight >2500 g in VT group than in twin group (77.8% vs. 25.4%, P Conclusion: Our study finding suggests better perinatal outcomes for ART pregnancies undergoing spontaneous reduction in first trimester compared to those pregnancies which continue as twins.

The Vanishing Twin Syndrome: Two cases of extreme malformations associated with vanished twins.

Two cases of devastating fetal malformations associated with vanished monochorionic twins were identified upon review of pathology files. A 35 year-old G1P0 woman and 36 year-old G3P1 woman were both diagnosed with an intrauterine twin gestation via transvaginal ultrasound at 10 weeks. The spectrum of fetal anomalies ranged from omphalocele, bilateral upper extremity and unilateral lower extremity hypoplasia, to craniofacial malformation with diaphragmatic hernia. On histopathologic examination, the placentas demonstrated vascular anastomoses between the surviving co-twin and the "vanished" fetal sac. We propose anastomotic placental vasculature as a contributing factor to the observed fetal malformations. Additionally, genetic or teratogenic factors may have been attributed to the demise of the first twin and the anomalies seen in the other twin. While such instances are rare, they are important to consider when counseling patients regarding outcomes associated with a monochorionic vanished twin.

Analysis of pregnancy outcomes for survivors of the vanishing twin syndrome after in vitro fertilization and embryo transfer

ObjectiveThe purpose of this study was to compare pregnancy outcomes of in vitro fertilization (IVF) singletons diagnosed with vanishing twin syndrome with control pregnancies originating as singleton pregnancies and with twin pregnancies. Study designThe current research included 206 survivors of a vanished co-twin, 1730 primary singletons and 662 primary twins. The study group was subdivided according to gestational age at the time of vanishing to give groups of early (≤12 weeks, group A) and late (>12 weeks, group B) survivors. Pregnancy outcomes were compared among study groups and controls. Results10.54% of all IVF singleton deliveries originated from a twin gestation. Group A showed similar mean gestational age (P=0.148) but higher proportion of preterm delivery (P=0.000), extremely preterm delivery (P=0.000), low birth weight (P=0.000) and very low birth weight (P=0.000) when compared with singleton controls. The comparison between group B and the singleton controls revealed dramatically higher frequency of preterm delivery (P=0.000), extreme preterm delivery (P=0.000), low birth weight (P=0.000), very low birth weight (P=0.000) and neonatal mortality (P=0.000). When compared with twin controls, group A showed lower risk of adverse pregnancy outcomes; in contrast, group B still showed significant higher adverse risk. ConclusionsIVF singletons with a vanished co-twin had a higher rate of adverse pregnancy outcomes in terms of preterm delivery and low birth weight, compared with IVF pregnancies that were originally singleton and twins, and the risk is increased with increasing gestational age at the time of vanishing.

Vanishing Twin Syndrome is Associated With Adverse Perinatal Outcomes in Fresh In Vitro Fertilization Cycles [23G

INTRODUCTION: To investigate whether the presence of a vanishing sac (VS) is associated with adverse perinatal outcomes in women undergoing fresh in vitro fertilization (IVF)—embryo transfer (ET) cycles. METHODS: Retrospective cohort study of women with live singleton births with and without a VS after fresh IVF-ET between January 2004 and June 2013. Baseline demographics and ovarian stimulation response between the two groups were compared. Additional characteristics compared included incidence of preterm birth (PTB), birth weight, low birth weight (LBW), very low birth weight (VLBW), and term LBW. Odds ratios (OR) with 95% confidence intervals (CI) were calculated and adjusted with multivariate logistic regression analysis when indicated. RESULTS: 4049 patients with live singleton births met inclusion criteria—853 and 3196 with and without a VS, respectively. There was no difference in the baseline demographics or ovarian stimulation response between the groups. The VS group had a lower overall birth weight compared to the group without a VS (3279.5±369.9 grams vs 3368.6±567.5 grams; P<.01). The findings of a VS was also associated with an increased odds of overall LBW (OR 1.75, 95% CI 1.36–2.25; P<.01) and an increased odds of term LBW (OR 3.44, 95% CI 2.14–5.53; P<.01). VS was not associated with a higher incidence of PTB or overall VLBW. CONCLUSION: Our findings suggest that a VS is associated with lower overall birth weight and higher odds of overall LBW and term LBW in live singleton births after fresh IVF-ET cycles.

ISUOG Practice Guidelines: role of ultrasound in twin pregnancy.

ISUOG Practice Guidelines: role of ultrasound in twin pregnancy.

Two consecutive singleton pregnancies versus one twins pregnancy as preferred outcome of in vitro fertilization for mothers and infants: a retrospective case–control study

Objective Many infertile couples request a multiple embryo transfer because they desire more than one child. Based on this consideration, the current study aimed to compare the reproductive and perinatal outcomes of two consecutive singleton pregnancies versus one twin pregnancy in a large cohort of in vitro fertilization (IVF) patients.Research design and methods Retrospective analysis of data from patients with clinical twin pregnancy after IVF fresh cycles and from patients with two consecutive IVF fresh cycles and clinical singleton pregnancy.Main outcome measures Miscarriage rate, delivery rate, gestational age at birth, neonatal birth weight, and perinatal complications. A sub-analysis of data according to vanishing twin syndrome (VTS) was also performed.Results A total of 18,703 autologous fresh cycles were analyzed. One hundred seven patients had two consecutive singleton clinical pregnancies, whereas one clinical twin pregnancy occurred in 641 women. In patients who had two consecutive singleton clinical pregnancies the rates of overall pregnancies lost (odds ratio [OR] 4.9, 95% confidence interval [CI] 3.4, 6.9) and live births (OR 0.2, 95% CI 0.1, 0.3) were, respectively, higher and lower when compared to patients who had one clinical twin pregnancy. That data did not change after sub-analysis for VTS. The overall risk of perinatal complications was significantly higher in patients who had one twin delivery rather than patients who had two consecutive singleton deliveries (OR 31.8, 95% CI 14.1, 71.5). No difference between groups was detected in terms of intrauterine/neonatal deaths, perinatal mortality and neonatal intensive care unit admission. Data did not change after adjusting for confounders.Conclusions When compared with two consecutive singleton pregnancies, twin pregnancies are characterized by higher success rates but worse perinatal outcomes irrespectively of VTS. Well designed prospective controlled studies are needed to confirm or rebut current retrospective findings.

Perinatal Risks Associated with Early Vanishing Twin Syndrome following Transfer of Cleavage- or Blastocyst-Stage Embryos.

Objective. To investigate whether the perinatal risks associated with early vanishing twin (VT) syndrome differ between cleavage- or blastocyst-stage embryo transfers (ET) in fresh in vitro fertilization (IVF) cycles. Methods. Retrospective, single-center, cohort study of IVF cycles with fresh cleavage- or blastocyst-stage ETs resulting in a live singleton birth. The incidence of preterm birth (PTB), low birth weight (LBW), and very low birth weight (VLBW) was compared between cleavage- and blastocyst-stage ET cycles complicated by early VT. Results. 7241 patients had live singleton births. Early VT was observed in 709/6134 (11.6%) and 70/1107 (6.32%) patients undergoing cleavage-stage and blastocyst-stage ETs, respectively. Patients in the blastocyst-stage group were younger compared to the cleavage-stage group. The cleavage-stage group had a similar birth weight compared to the blastocyst-stage group. There was no difference in the incidence of PTB (9.87% versus 8.57%), LBW (11.1% versus 11.4%), or VLBW (1.13 versus 1.43%) when comparing the cleavage-stage early VT and blastocyst-stage early VT groups, even after adjustment with logistic regression. Conclusions. Our study highlights that the adverse perinatal risks of PTB, LBW, and VLBW associated with early VT syndrome are similar in patients undergoing cleavage-stage or blastocyst-stage ETs during fresh IVF cycles.

Assisted reproductive technology and pregnancy outcomes.

In 2004, two systematic reviews drew attention to the outcomes of singleton pregnancies from assisted reproductive technology (ART) (Helmerhorst et al. BMJ 2004;328:261–5; Jackson et al. Obstet Gynecol 2004;103:551–63). Although their inclusion criteria differed, the conclusions were remarkably similar, demonstrating significantly worse pregnancy outcomes compared with non-assisted pregnancies. Both raised the question of how much of the poor outcome related to the characteristics of the women relying on ART and how much related to ART itself. This has remained a puzzle (Keirse & Helmerhorst. In: Pijnenborg et al., editors. Placental Bed Disorders. Cambridge: Cambridge University Press; 2010. p. 207–28) as there are several factors that hamper a clear-cut answer. Women who undergo ART differ in many respects from those who conceive naturally, not least in age, parity and the known or unknown reasons for their subfertility. ART involves different techniques, which may influence gametes, zygotes and implantation in several ways that are not fully understood. Not all singleton pregnancies after ART start as singletons. Some suffer from a vanishing twin syndrome that is associated with poorer outcomes. All is further compounded by an obstetric tendency to intervene in such pregnancies before problems arise (Keirse et al. Paediatr Perinat Epidemiol 2009;23:522–32). The study of DoPierala (BJOG 2016;123:1320–8), is a commendable attempt to disentangle the effect of subfertility from that of its treatment. Using a unique patient identification number, they linked women in a maternity database to women in a fertility centre database over nearly two decades. Linking exposures in one database to outcomes in another is always problematic. Although data on low birthweight and gestational age were missing for less than 0.02%, data on small for dates were missing for 4.6%. Only 44% of women attending the fertility clinic had received any treatment and, for 7.9%, it was unknown whether treatment had been instituted. In women without fertility centre history, there were 21 twin pregnancies per 1000 pregnancies [95% confidence interval (CI), 19.8–22.2] compared with only 14 per 1000 (95% CI, 13.I–15.1), including assisted conceptions, in Scotland in 2004 (EURO-PERISTAT project, 2008, www.europeristat.com). Nonetheless, the study convincingly demonstrates that a history of subfertility by itself is a risk factor for several adverse pregnancy outcomes, including pre-eclampsia, antepartum haemorrhage, placenta praevia, preterm birth, low birthweight and childbirth interventions. Although these data seem to indicate no difference in outcome between treated and non-treated subfertility, such a conclusion is not warranted in view of the concerns mentioned above. There is sufficient circumstantial evidence that ovarian stimulation is at least partially responsible for poor pregnancy outcomes after ART. Differences in outcome with natural conceptions seem to be similar for ovarian stimulation with and without in vitro fertilisation (IVF), whereas pregnancies from the transfer of thawed embryos, which is usually performed in natural cycles, appear to do better (Keirse & Helmerhorst, 2010). The Scottish data do not change the findings of a systematic review (Keirse & Helmerhorst, 2010) showing that different ART techniques have differential effects on the preterm birth rate. Although little can be concluded from the twin data, they reinforce the concept that the largest potential for reducing the frequency of adverse outcomes after ART is in the avoidance of multiple pregnancies, which – at least in theory – ought to be easier than with natural conceptions (Keirse & Helmerhorst, 2010). The International Committee of Medical Journal Editors (ICMJE) disclosure form is available online as supporting information. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.

Aplasia cutis congenita: A case report and literature review.

Aplasia cutis congenita (ACC) is a rare condition with an unclear pathogenic mechanism, although the condition has been suggested to occur as a result of the disrupted development or degeneration of skin in utero. ACC associated with fetus papyraceus has been described in numerous studies. Although there have been several reports of ACC, surgical treatment of ACC using the head as a site of donor skin is rarely reported. The present study describes the case of a 1-week-old patient with ACC that was healed by skin grafting, using the scalp as the donor site. The outcome of the procedure showed that the use of the scalp as a donor skin site for grafting is an effective treatment for large and deep ACC lesions arising on sites other than the head.

THE "VANISHING TWIN" SYNDROME - A MYTH OR CLINICAL REALITY IN THE OBSTETRIC PRACTICE?

Background: A case of triplets pregnancy after IVF ET, ended with a spontaneous reduction of one of the fetuses. The patient was with secondary infertility, with two unsuccessful preceding IVF Procedures and reduced ovarian reserve. A short flare up protocol with recombinant FSH was performed and three embryos were transferred on day three. An intrauterine pregnancy and three gestational sacs with CA (cardiac activity) were visualized via transvaginal ultrasonography by the twenty-first day. After the patient refused to go through an embrioreduction, during a routine sonography by the fourteenth week, the death of one fetus was reported. The pregnancy was finalized with the Cesarean delivery of two newborn in good health by thirtyseventh week. During the regular examination of the placentas, a mummified fetus -fetus papyraceus was found Objective: To report a case of “Vanishing Twin” syndrome. Design: Case report. Methods: Clinical presentation, examination and ultrasound were consistent with diagnosis “Vanishing Twin” syndrome. Conclusion: The frequency of multi fetal births considerably increased after ART.

Fetus papyraceus causing dystocia in a rural setting: a case report

IntroductionFetus papyraceus is a rare condition which describes a mummified fetus in a multiple gestation pregnancy in which one fetus dies and becomes flattened between the membranes of the other fetus and uterine wall. We report a case of fetus papyraceus diagnosed during labor as a result of arrested descent.Case presentationA 23-year-old Sukuma woman, gravida 2, para 1 presented to an maternity emergency unit of Sengerema Designated District hospital at a gestation age of 35+5 weeks as a referral from a rural health center due to arrested descent despite being in active labor for the past 8 hours. On vaginal examination, her cervix was 6cm dilated; fully effaced, presenting part was at station −3. A sharp and solid object-like thing was felt on the right side of her cervix. Due to uncertainty of the presenting part together with arrested descent, a decision was reached to deliver her by caesarean section. A twin gestation was identified during caesarean section: one being a male baby in cephalic presentation, weighing 1.9kg with Apgar score 8 in first minute and 9 in fifth minute with its own normal placenta and membranes. There was another atrophied placenta with calcifications without a cord and with mummified fetal bones on the anterior to the lower segment at the level of the internal orifice of the uterus. The atrophied placenta and mummified fetal bones weighed 200gms. One unit of blood was transfused intraoperatively due to severe anemia prior to surgery. Both the mother and the baby were discharged home in good condition.ConclusionsThe primary concern for fetus papyraceus is its effect on the surviving fetus and on the mother. To avoid possible complications, the intrauterine diagnosis of fetus papyraceus by serial ultrasound examinations and routine placental examination to search for fetus papyraceus is mandatory.

Aplasia Cutis Congenita Association with Fetus Papyraceus

Aplazia kutis konjenita AKK derinin lokalize veya genis alanlar seklinde yoklugu ile karakterize nadir bir anomalidir. Genellikle skalpta gorulmekle birlikte, tek veya multipl lezyonlar seklinde vucudun herhangi bir yerinde bulunabilir. On bin dogumda bir gorulen AKK izole bir lezyon olarak ortaya cikabildigi gibi, yarik damak/dudak, sindaktili, parmaklarin yoklugu, goz anomalileri ve konjenital kalp hastaliklari ile birlikte gorulebilir. AKK’nin oldukca nadir gorulen bir formu da intrauterin ex olan ikiz esine bagli gelisen formudur. Buyuk lezyonlar cerrahi onarima gerek duyarken, kucuk defektler spontan re-epitelizasyon ile iyilesebilir. Bu yazida; nadir olarak gorulen, fetus papyraceus ile iliskili olarak govdesinde AKK gelisen erkek olgu sunulmustur

Aplasia Cutis Congenita Associated with Fetus Papyraceus.

Aplasia cutis congenita (ACC), or congenital absence of skin, is a heterogeneous condition that may be due to varied mechanisms. ACC has rarely been reported in association with fetus papyraceus, representing a peculiar phenotype of ACC. We present six new cases of neonates born with symmetric ACC associated with intrauterine fetal demise of co-twins during the late first or early second trimester.

Vanishing twin syndrome: is it associated with adverse perinatal outcome?

To evaluate whether vanishing twin syndrome (VTS) is associated with adverse perinatal outcome. A retrospective cohort study investigating the impact of VTS on perinatal outcome was conducted. Parturients were classified into three groups: those pregnancies that started with double fetal sacs and spontaneously reduced into one (VTS), those with dichorionic twins, and those with singleton pregnancies. Statistical analysis included multiple logistic regression models to control for possible confounders. Tertiary university medical center. The study involved 252,994 singleton deliveries between the years 1988 and2012. None. The impact of VTS on perinatal outcome. During the study period, 278 pregnancies with VTS were compared with 1,801 pregnancies of dichorionic twins and 252,994 pregnancies of singletons. A significant linear association was documented among the three groups and various adverse outcomes, including gestational diabetes mellitus (GDM), intrauterine growth restriction (IUGR), very low birth weight (VLBW), and perinatal mortality. The higher risk was noted in the VTS group, and the lowest in singletons. Using multivariable logistic regression models, while controlling for confounders such as fertility treatment and maternal age, VTS (as compared with singletons) was found to be an independent risk factor for several adverse perinatal outcomes including GDM, IUGR, VLBW, low Apgar scores, and perinatal mortality (adjusted odds ratios with their respective 95% confidence intervals, 1.4 [1.01-2.0], 2.7 [1.7-4.3], 6.9 [4.7-10.2], 1.9 [1.1-3.3], 2.4 [1.2-4.5]). Pregnancies with VTS are associated with an adverse perinatal outcome, even after controlling for confounders such as fertility treatment and maternal age.

Microchimerism and thyroid disorders: current knowledge and future prospects

This review will provide an overview of a novel phenomenon in medicine and endocrinology known as microchimerism (MC). MC is defined as the long-term presence of genetically distinct populations of cells in peripheral blood and tissues of individual. This condition may be caused by the transplacental bidirectional cell trafficking between mother and fetus during pregnancy. Other sources are the passage from a twin or a vanished twin and iatrogenic interventions such as organ transplantation and blood transfusion. Long-term consequences of MC and its influence on woman's health are under active investigation. Recent studies have shown a broad spectrum of its biological effects either beneficial or adverse. MC has been suggested to play a key role in the pathogenesis of autoimmune diseases. It is assumed that microchi-meric cells could initiate a versus or host versus graft reactions. MC has been extensively studied in autoimmune thyroid diseases (AITD). MC could explain the higher prevalence of AITD in females and frequent manifestation during the postpartum period. It is proposed that microchimeric cells could reduce the risk of cancer development and be a part of tissue repair. MC has also been investigated in papillary thyroid cancer. Further studies of this phenomenon are mandatory to get more insights about its role in thyroid cancer and AITD development. This could provide novel therapeutic, preventive or prognostic perspectives regarding these diseases.

Unexplained False Negative Results in Noninvasive Prenatal Testing: Two Cases Involving Trisomies 13 and 18.

Noninvasive prenatal testing (NIPT) validation studies show high sensitivity and specificity for detection of trisomies 13, 18, and 21. False negative cases have rarely been reported. We describe a false negative case of trisomy 13 and another of trisomy 18 in which NIPT was commercially marketed directly to the clinician. Both cases came to our attention because a fetal anatomy scan at 20 weeks of gestation revealed multiple anomalies. Karyotyping of cultured amniocytes showed nonmosaic trisomies 13 and 18, respectively. Cytogenetic investigation of cytotrophoblast cells from multiple placental biopsies showed a low proportion of nontrisomic cells in each case, but this was considered too small for explaining the false negative NIPT result. The discordant results also could not be explained by early gestational age, elevated maternal weight, a vanishing twin, or suboptimal storage or transport of samples. The root cause of the discrepancies could, therefore, not be identified. The couples involved experienced difficulties in accepting the unexpected and late-adverse outcome of their pregnancy. We recommend that all parties involved in caring for couples who choose NIPT should collaborate to clarify false negative results in order to unravel possible biological causes and to improve the process of patient care from initial counseling to communication of the result.

College-age twins: university admission policies / twin research: birth weight and neuromotor performance; transfusion syndrome markers; vanishing twins and fetal sex determination; mz twin discordance for wilson's disease / media: big at birth; planned separation of conjoined twins; x factor twins; Cinema: the identical.

There is a lack of research findings addressing the unique college admissions issues faced by twins and other multiples. The advantages and disadvantage twins face, as reported by college administrators, twins and families are reviewed. Next, recent research addressing twins' birth weight and neuromotor performance, transfusion syndrome markers, the vanishing twin syndrome and monozygotic (MZ) twin discordance for Wilson's disease is described. News items concerning the birth of unusually large twins, the planned separation of conjoined twins, twin participants in the X Factor games and a film, The Identical, are also summarized.

Detection of triploid, molar, and vanishing twin pregnancies by a single-nucleotide polymorphism–based noninvasive prenatal test

We sought to determine the ability of single-nucleotide polymorphism-based noninvasive prenatal testing (NIPT) to identify triploid, unrecognized twin, and vanishing twin pregnancies. The study included 30,795 consecutive reported clinical cases received for NIPT for fetal whole-chromosome aneuploidies; known multiple gestations were excluded. Cell-free DNA was isolated from maternal blood samples, amplified via 19,488-plex polymerase chain reaction, and sequenced. Sequencing results were analyzed to determine fetal chromosome copy number and to identify the presence of additional fetal haplotypes. Additional fetal haplotypes, indicative of fetal triploidy, vanishing twin, or undetected twin pregnancy, were identified in 130 (0.42%) cases. Clinical confirmation (karyotype for singleton pregnancies, ultrasound for multifetal pregnancies) was available for 58.5% (76/130) of cases. Of the 76 cases with confirmation, 42.1% were vanishing twin, 48.7% were viable twin, 5.3% were diandric triploids, and 3.9% were nontriploid pregnancies that lacked evidence of co-twin demise. One pregnancy had other indications suggesting triploidy but lacked karyotype confirmation. Of the 5 vanishing twin cases with a known date of demise, 100% of losses occurred in the first trimester; up to 8 weeks elapsed between loss and detection by NIPT. This single-nucleotide polymorphism-based NIPT successfully identified vanished twin, previously unrecognized twin, and triploid pregnancies. As vanishing twins are more likely to be aneuploid, and undetected residual cell-free DNA could bias NIPT results, the ability of this method to identify additional fetal haplotypes is expected to result in fewer false-positive calls and prevent incorrect fetal sex calls.

First and second trimester maternal serum markers in pregnancies with a vanishing twin.

The aim of this study was to assess the concentration of the first and second trimester maternal serum markers in pregnancies with a vanishing twin. This is a retrospective case-control study of pregnancies screened for Down syndrome in one Ontario center. Singleton pregnancies with ultrasound evidence of a vanishing twin were identified, and each was matched with five normal singleton controls for ethnicity, maternal age, gestational age, and blood sampling date. The median MoM of the first and second trimester serum markers was compared between cases and controls. The differences were assessed using the Mann-Whitney U-test. The study included 174 pregnancies that had a vanishing twin. Compared with control pregnancies, pregnancy associated plasma protein A increased by 21% (p = 0.0026), alpha-fetoprotein (AFP) increased by 10% (p < 0.0001), and dimeric inhibin A (DIA) increased by 13% (p = 0.0470) in pregnancies with a vanishing twin. Unconjugated oestriol and total human chorionic gonadotrophin were not significantly changed in these pregnancies. Pregnancy associated plasma protein A is not an adequate marker for pregnancies with a vanishing twin. The impact of elevated AFP on risk estimation is offset by that of DIA to certain extent. Further studies are needed to establish an adequate adjustment method for AFP and DIA to improve the accuracy of screening results for these pregnancies.

Pitfalls in noninvasive fetal RhD and sex determination due to a vanishing twin

What's already known about this topic? Risk of misdiagnosis in NIPT carried out by cfDNA analysis in presence of vanishing twins. Importance of ultrasound monitoring since early gestational age in case of NIPT.What does this study add? Precise monitoring of the cfDNA released from a vanishing twin in a noninvasive fetal RhD and sex determination. Exhaustive follow‐up of pregnancy since delivery.