Monoamniotic Twin Pregnancy Research Articles

Perinatal Outcome of Monoamniotic Twin Pregnancies

To study perinatal mortality and neonatal morbidity in a large cohort of monoamniotic twin pregnancies with special emphasis to the gestational age-specific mortality. The study included monoamniotic twin pregnancies delivered in 10 perinatal centers in the Netherlands between January 2000 and December 2007. A total of 98 monoamniotic pregnancies were included. The perinatal mortality rate (20 weeks of gestation through 28 days of life) was 19%; after exclusion of fetuses with lethal anomalies, the rate was 17%. After 32 weeks of gestation, only two pregnancies were complicated by perinatal mortality (4%). The incidence of twin-twin transfusion syndrome was 6%. The incidence of congenital heart anomalies and cerebral injury was 4% and 5%, respectively. The current incidence of perinatal mortality in monoamniotic twins is considerably lower than in previous decades, but it is still high and occurs throughout pregnancy. III.

Placental Characteristics of Monoamniotic Twin Pregnancies in Relation to Perinatal Outcome

Objective To study placental characteristics in relation to perinatal outcome in 55 pairs of monochorionic monoamniotic (MA) twins. Methods Between January 1998 and May 2008 55 pairs of MA twins were delivered in 4 tertiary care centers and analysed for mortality, birth weight discordancy and twin-to-twin transfusion syndrome (TTTS) in relation to type of anastomoses, type and distance between cord insertions and placental sharing. Five acardiac twins, 2 conjoined twins, 4 higher order multiples and one early termination of pregnancy were excluded, leaving 43 MA placentas for analysis. Of these 43, one placenta could not be analysed for placental vascular anastomoses due to severe maceration after single intra-uterine demise leaving 42 placentas for analysis of anastomoses. Results Arterio-arterial (AA), venovenous (VV) and arteriovenous (AV) anastomoses were detected in 98%, 43% and 91% of MA placentas, respectively. Velamentous cord insertion was found in 4% of cases. Small distance between both umbilical cord insertions (<5 cm) was present in 53% of MA placentas. Overall perinatal loss rate was 22% (19/86). We found no association between mortality and type of anastomoses, type and distance between cord insertions and placental sharing. The incidence of TTTS was low (2%) and occurred in the only pregnancy with absent AA-anastomoses. Conclusion Perinatal mortality in MA twins was not related to placental vascular anatomy. The almost ubiquitous presence of compensating AA-anastomoses in MA placentas appears to prevent occurrence of TTTS.

Intrauterine programming of the cardiovascular system

Intrauterine programming of the cardiovascular system

Actitud ante el diagnóstico prenatal de las complicaciones del cordón umbilical en gemelos monoamnióticos

Monoamniotic twin pregnancies are rare (1/10,000 pregnancies), but are associated with a high perinatal mortality rate (30-70%). Fetal death usually results from cord entanglement and/or knots, which are the most representative and hazardous complications. Currently, early and accurate ultrasound diagnosis of this type of twinning can be performed. Furthermore, several ultrasound signs have recently been reported that aid recognition of umbilical cord abnormalities and identification of blood flow compromise. Intensive monitoring with nonstress tests and ultrasonographic follow-up combined with improved neonatal care can decrease the mortality rate in monoamniotic pregnancies by 10%. However, the management of these pregnancies remains controversial. We report a case of knotting of the cords, prenatally detected at 31 weeks. The ultrasonographic findings allowed the obstetric management to be reconsidered, with excellent neonatal outcomes.

Prenatal Diagnosis of Ascites With Hydrometrocolpos and Uterus Didelphys in a Monoamniotic Twin Pregnancy

Hydrometrocolpos is a rare congenital disorder very rarely reported on prenatal sonography. A female fetus may have a dilated vagina and uterus due to accumulation of mucous secretions in the genital tract. The sonographic appearance is of cystic dilatation of these organs due to genital tract obstruction secondary to an imperforate hymen, a transverse vaginal membrane, or some degree of vaginal atresia. 1 Although the neonatal presentation is known, to our knowledge, no clear data exist regarding the fetal presentation. Few reports on the prenatal diagnosis of hydrometrocolpos by sonography have been published in which diagnosis and even in utero treatment were suggested. 2 In this report, we aim to describe the prenatal sonographic appearance and prenatal evaluation of a unique case of hydrometrocolpos associated with ascites and uterus didelphys in one fetus of a monochorionic, monoamniotic gestation.

Discrepancy of prenatal findings in a monochorionic monoamniotic twin pregnancy – Infantile myofibromatosis

Introduction: Monoamniotic twin pregnancies are characterized by an increased rate of cord injuries due to entanglement and of prenatal malformations.

Inpatient versus Outpatient Management of Monoamniotic Twins and Outcomes

A recent literature review holds that approximately one in 10 cases of monoamniotic twinning ends with perinatal death. An entangled umbilical cord may be fatal and is not a predictable complication. This multicenter retrospective records review was undertaken to learn whether outcomes might be improved by hospitalization when monoamniotic twins are at 24 to 28 weeks gestation and close fetal surveillance is maintained until delivery at 32 to 34 weeks. Review of a recent 10-year period at 4 centers totaling approximately 15,000 deliveries annually yielded 23 sets of monoamniotic twins, 11 managed as inpatients and 12 given outpatient care. Women in the inpatient group had continuous external fetal monitoring and underwent ultrasound (to monitor fetal growth) and Doppler flow studies at 4-week intervals. Outpatient management included nonstress testing or biophysical profiling at least 3 times a week. There were no fetal deaths in the inpatient group, but 3 such deaths occurred with outpatient management. Inpatients had gestational ages of 30 to 36 weeks when delivered. There were 7 elective operative deliveries in the inpatient group, and 4 sections were done because of a nonreassuring fetal heart tracing. Eleven infants had respiratory distress syndrome; 3, intraventricular hemorrhage; 3, anomalies; and one, sepsis. Two infants were apparently free of complications. In the outpatient group, gestational ages at delivery ranged from 27 to 34 weeks. Three cesarean sections were done electively and 6 others because of a nonreassuring fetal heart tracing. There were 2 cases each of preterm labor and intrauterine fetal demise and one each of severe preeclampsia, increased liver enzymes, and abruption. Sixteen infants in this group had respiratory distress syndrome, 4 had sepsis, and one each had intraventricular hemorrhage and atrial septal defect. Three infants each had patent ductus arteriosis and retinopathy of prematurity, whereas 4 were free of complications. It is not likely that a randomized trial comparing inpatient with outpatient management of monoamniotic twin pregnancies will prove feasible. Pending such a study, the investigators propose that inpatient management be considered.

High perinatal survival in monoamniotic twins managed by prophylactic sulindac, intensive ultrasound surveillance, and Cesarean delivery at 32 weeks' gestation

Increased perinatal mortality in monoamniotic twin pregnancies is attributed to cord accidents in utero and at delivery. We evaluated the following parameters in monoamniotic pregnancies: (1) the incidence of cord entanglement; (2) the effect of sulindac on amniotic fluid volume and stability of fetal lie; and (3) the perinatal outcome with our current management paradigm. This is a retrospective review of monoamniotic pregnancies of >or=20 weeks' gestation managed with serial ultrasound surveillance, medical amnioreduction and elective Cesarean delivery at 32 weeks' gestation. Mean amniotic fluid index (AFI) and change in AFI in monoamniotic pregnancies managed with oral sulindac was compared with 40 gestation-matched monochorionic-diamniotic controls. Among 44 monoamniotic pregnancies, 20 with two live structurally normal twins at 20 weeks' gestation satisfied the inclusion criteria. All fetuses survived to 28 days postnatally despite early prenatal cord entanglement in all but one case. Whereas AFI remained stable throughout gestation in the controls, the AFI fell in those patients on sulindac from a mean value of 21.0 cm (95% CI, 18.5-23.6 cm) at 20 weeks to a mean of 12.4 cm (95% CI, 10.1-14.6 cm) at 32 weeks (ANOVA P across gestation = 0.001) but mainly remained within normal limits. Fetal lie was stabilized in 11/20 cases in the monoamniotic group compared with 13/40 in the control group (P < 0.0001). Cord entanglement appears unpreventable, as it typically occurs in early pregnancy. Sulindac therapy reduces AFI, leads to more stable fetal lie, and may prevent intrauterine death by diminishing the risk of constricting cords that are already entangled. Perinatal survival in monoamniotic pregnancies managed by a regime of sulindac from 20 weeks' gestation, close ultrasound surveillance and elective abdominal delivery at 32 weeks' gestation seems empirically higher than that in the literature.

P05.16: Monoamniotic twins discordant for anencephaly managed expectantly with amnioreduction: case report

Monoamniotic twin pregnancy discordant for anencephaly (MATDA) is a rare occurrence with only nine prior reported cases. Selective termination has been advocated in managing this kind of twins. We report the case, including expectant management with serial amniocentesis and a good outcome. The case was a 22-year-old primigravida woman diagnosed with MATDA at 24 weeks. Ultrasound findings included anencephaly, cervical rachischisis, a single placenta, absent membrane, severe polyhydramnios. Cordo- and placentocentesis showed a normal karyotype for the twins. Serial amnioreductions were performed. Amniotic fluid samples were submitted to the shake (Clements) test for fetal lung maturity assessment. The woman was managed expectantly until 35 weeks when a preterm labor began and Cesarean section was performed. The surviving male infant weighed 2100 g. and had a deformed right auricle and atresia of the auditory canal. He was discharged home in good condition one month later.

EMBARAZO GEMELAR MONOAMNIÓTICO: EXPERIENCIA DE UNA SERIE DE CASOS EN EL HOSPITAL PADRE HURTADO

SUMMARY The perinatal outcome of 7 cases of monoamniotic twin pregnancies is analysed. All cases with live foetus were resolved by caesarean section at 32 week. The perinatal mortality rate of this series was 143/ 1000 live birth.

Monoamniotic twin pregnancy: a review of contemporary practice

Monoamniotic twins represent an uncommon manifestation of the monozygotic twinning process (1% of monozygotic twins). They are the result of ovum division beyond 8 days postconception and are characterised by a single amnion and a single yolk sac. There may be two or one (conjoined twins) embryos present. This form of twinning is notable for an increase in perinatal loss (10-15% in contemporary series of prenatally recognised cases). Congenital anomalies, umbilical cord entanglement/accidents, preterm birth and intrauterine growth restriction primarily account for this increased perinatal mortality rate. Diagnosis is most typically by ultrasound, with the inability to distinguish a dividing membrane between the fetuses the most typical feature. There are diagnostic pitfalls (oligohydramnios in one twin with closely adherent membrane) and accuracy in diagnosis is central to appropriate pregnancy management. Obstetric management protocols are based on several retrospective case series, and there is a paucity of large well-controlled studies to provide guidance in the management of monoamniotic twin pregnancies. The prevention of antepartum death from umbilical cord entanglement is one of the central management issues; however, the available techniques of antepartum surveillance have a variable performance in predicting this event.

Monoamniotic Twin Pregnancy Discordant for Body Stalk Anomaly

Journal of Ultrasound in MedicineVolume 24, Issue 12 p. 1739-1744 Case Report Monoamniotic Twin Pregnancy Discordant for Body Stalk Anomaly Case Report With Nosologic Implications Alex C. Vidaeff MD, MPH, Corresponding Author Alex C. Vidaeff MD, MPH alex.c.vidaeff@uth.tmc.edu Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Address correspondence to Alex C. Vidaeff, MD, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, 6431 Fannin St, Suite 3.604, Houston, TX 77030 USA.Search for more papers by this authorAdam N. Delu MD, Adam N. Delu MD Department of Radiology, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this authorJeannie B. Silva RDMS, Jeannie B. Silva RDMS Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this authorEdward R. Yeomans MD, Edward R. Yeomans MD Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this author Alex C. Vidaeff MD, MPH, Corresponding Author Alex C. Vidaeff MD, MPH alex.c.vidaeff@uth.tmc.edu Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Address correspondence to Alex C. Vidaeff, MD, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, 6431 Fannin St, Suite 3.604, Houston, TX 77030 USA.Search for more papers by this authorAdam N. Delu MD, Adam N. Delu MD Department of Radiology, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this authorJeannie B. Silva RDMS, Jeannie B. Silva RDMS Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this authorEdward R. Yeomans MD, Edward R. Yeomans MD Division of Maternal-Fetal Medicine, Department of Obstetrics, Gynecology, and Reproductive Sciences, University of Texas-Houston Medical School, Houston, Texas USA.Search for more papers by this author First published: 01 December 2005 https://doi.org/10.7863/jum.2005.24.12.1739Citations: 12Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume24, Issue12December 2005Pages 1739-1744 RelatedInformation

Prenatal Evaluation of an Extremely Rare and Bizarre Case of Cephalothoracopagus Monosymmetros Janiceps Twins

Es wird ein sehr seltener Fall eineiiger Zwillinge vorgestellt. Die Diagnose von Cephalothoracopagus-Zwillingen wurde in der 18. Schwangerschaftswoche durch Ultraschalluntersuchung gestellt. Das Szintigramm zeigte eine eineiige Zwillingsschwangerschaft mit nur einem Fruchtwassersack. Die Feten hatten einen gemeinsamen Kopf mit nur einem Gesicht, einen Brustkorb mit zwei Herzen, zwei getrennte Becken mit vier Nieren, zwei Blasen und acht normale Glieder. Die innere Schädelstruktur wies zwei Gehirnhemisphären mit zwei normalen lateralen Hirnkammern im Supratentorium auf, während die hintere Schädelgrube doppelt vorhanden war mit insgesamt vier Kleinhirnhemisphären. Die eineiigen Zwillinge hatten eine verschmolzene Nabelschnur mit fünf Gefäßen und bei einem der Zwillinge wurde ein Herzfehler festgestellt. Die Schwangerschaft wurde abgebrochen und eine anschließende Autopsie der Zwillinge bestätigte alle mit Ultraschall gefundenen Befunde. Dieser Fall stellt einen der seltensten Fälle von Cephalothoracopagus-Zwillingen dar: Janiceps monosymmetros syncephalus mit einem einzigen, normalen Gesicht.

Monoamniotic twins discordant for anencephaly managed conservatively with good outcomes: two case reports and a review of the literature

Monoamniotic twin pregnancy discordant for anencephaly (MATDA) is a rare occurrence with only seven prior reported cases. Selective termination has been advocated in managing discordant monoamniotic twins. We report two cases managed expectantly with good outcomes and review other previously reported cases. The first case was a primigravid woman diagnosed with MATDA at 18 weeks. She was managed expectantly until 32 + 5 weeks when a Cesarean section was performed for preterm labor. The surviving female infant weighed 1610 g. The second case was a multigravid woman who was diagnosed with MATDA at 17 + 5 weeks and was managed as an outpatient. An emergency Cesarean section was performed at 31 weeks for non-reassuring monitoring and the surviving male infant weighed 1790 g. In both cases, the survivors were discharged home in good condition. A review of these two cases and those in the literature suggests that expectant management should be considered among management options for this rare condition.

Intensive management and early delivery reduce antenatal mortality in monoamniotic twin pregnancies

Intensive management and elective delivery between 32 and 35 weeks of monoamniotic twin pregnancies were suggested as improving perinatal outcome. We sought to evaluate this management as viewed by the outcome of monoamniotic twin pregnancies in our population. A retrospective systematic chart review of all monoamniotic twin pregnancies, diagnosed from January 1986 to June 2002, was performed in three medical centers. Demographics, pregnancy course, and perinatal outcome were evaluated. The management and outcome were compared between the group of survivors and the groups of intrauterine fetal demise (IUFD) and miscarriage. Thirty-three pairs of monoamniotic twins were identified. Excluded were three women, who chose to terminate the pregnancy. Total survival rate was 60% (of 60 fetuses, 36 were born alive, but one neonate died due to sepsis). None of the IUFD occurred in hospitalized patients, and two pairs of twins died after 32 weeks. In the 10 twin pairs who died in utero, cord entanglement was documented in eight (80%). There were two cases of twin discordance and two cases of twin-to-twin transfusion syndrome. One twin of the live-born group had congenital transposition of the great arteries. Furthermore, one of the hospitalized patients was delivered by means of an emergency cesarean section because of a non-reassuring non-stress test at 30 weeks. Women with monoamniotic twin pregnancies should be advised about the very high mortality and morbidity rate. Early diagnosis, close in-hospital antenatal surveillance starting at fetal viability, and elective delivery at 32 weeks would reduce the antenatal mortality.

Ultrasonographic signs of twin–twin transfusion syndrome in a monoamniotic twin pregnancy

Twin–twin transfusion syndrome (TTTS) is a complication of monochorionic pregnancies usually described in diamniotic but also in monoamniotic pregnancies1, 2. The syndrome is defined sonographically by the presence of polyhydramnios in one twin's sac (recipient twin) and oligohydramnios in the sac of the other twin (donor twin)3, 4. Other sonographic parameters include discordant bladder sizes, hydrops and abnormal Doppler studies of the arterial or venous circulation5. We report the case of a 24-year-old woman, gravida 2 para 1, who was referred to our department at 16 weeks of gestation with polyhydramnios in a monoamniotic monochorionic twin pregnancy. Ultrasound examination revealed discordant biometries, cord diameters and bladder sizes. Both cords were inserted on the placental margin and close to one another. Color Doppler and three-dimensional power Doppler showed large superficial anastomoses (Figure 1). An HDI 5000 (ATL, Courtaboeuf, France) ultrasound machine equipped with a 8–5 MHz broadband array was used. Doppler waveforms (umbilical artery and ductus venosus) were normal in Twin 1 (recipient) and indicated high-impedance flow in Twin 2 (donor). Follow-up at 19 weeks showed increased amniotic fluid index (32 cm) and reversed flow in the umbilical artery of Twin 2. Spontaneous resolution of polyhydramnios occurred at 26–28 weeks but biometries and bladder sizes remained discordant although the fetuses exhibited good activity and no effusion. At 29 + 4 weeks we observed biventricular cardiac hypertrophy in Twin 1 associated with tricuspid regurgitation and pulmonary artery hypertension (right ventricular pressure increased to 110 mmHg). A Cesarean section was performed at 30 weeks. Twin 1 weighed 1640 g with a 17 g/dL hemoglobin rate and he died postnatally at 22 h because of cardiac failure related to myocardial hypertrophy. Twin 2 weighed 1270 g with a 13 g/dL hemoglobin rate and he survived. Pathological examination of the placenta confirmed the monochorionic monoamniotic pregnancy with numerous vascular anastomoses (Figure 2). Three-dimensional power Doppler imaging demonstrating anastomosis (arrow) and the positions of the donor (D) and recipient (R) cords. Postnatal examination of the placenta demonstrating the discordant sizes of the donor (D) and recipient (R) cords. In this case we observed the main ultrasonographic signs of TTTS (polyhydramnios, discordance in bladder sizes and cord diameters and Doppler waveforms, arteriovenous placental anastomoses) and the evolution was consistent with an unbalanced blood flow (myocardial overload and polyglobulia (hemoglobin = 17 g/dL) in the recipient twin). In monoamniotic twin pregnancies the classical ultrasonographic sign of discordant amniotic sacs with deviated interfetal membrane can obviously not be observed. Nevertheless, polyhydramnios and discordant bladder sizes are currently considered to be sufficient evidence for the presence of unbalanced blood flow4. Some authors have attempted to explain why such a complication is rarely described in the literature. Monoamniotic and diamniotic-monochorionic placentas have different anastomotic patterns6, 7. The higher incidence of arterio-arterial anastomoses in monoamniotic twin pregnancies leads to more balanced anastomotic patterns and predicts that TTTS will occur approximately five times less often. We suggest close monitoring with fortnightly scans for all monochorionic pregnancies to detect the onset of TTTS. The first signs of TTTS based on polyhydramnios and discordant bladder sizes are easy to diagnose and warrant further investigation in a referral center to decide on the most appropriate management (observation, invasive procedures such as photocoagulation of the anastomoses, selective feticide, labor induction or Cesarean section). D. Gallot* , J.-P. Saulnier , D. Savary*, H. Laurichesse-Delmas* , D. Lemery* , * Maternal Fetal Medicine Unit, Maternité Hôtel-Dieu, CHU de Clermont-Ferrand, Boulevard Léon Malfreyt, 63003 Clermont-Ferrand cédex, France, Department of Pediatrics, Université d'Auvergne Clermont I, Hôtel-Dieu, CHU de Clermont-Ferrand, Boulevard Léon Malfreyt, 63003 Clermont-Ferrand cédex, France, JE 2447 ARDEMO, Université d'Auvergne Clermont I, Hôtel-Dieu, CHU de Clermont-Ferrand, Boulevard Léon Malfreyt, 63003 Clermont-Ferrand cédex, France

Prenatal diagnosis of an acardiac amorphous twin and the anomalous co-twin in a monoamniotic twin pregnancy

Prenatal diagnosis of an acardiac amorphous twin and the anomalous co-twin in a monoamniotic twin pregnancy

Intensive management and early delivery reduce antenatal mortality in monoamniotic twin pregnancies

Intensive management and early delivery reduce antenatal mortality in monoamniotic twin pregnancies

Successful selective termination at 17 weeks' gestation in monochorionic monoamniotic twin pregnancy affected by twin-twin transfusion syndrome and discordant for hypoplastic left heart syndrome

To report a successful selective feticide in a complicated monochorionic monoamniotic (MCMA) pregnancy. A case of MCMA pregnancy with severe twin-twin transfusion syndrome and discordant for hypoplastic left heart syndrome was diagnosed at 16 weeks' gestation. A complete ultrasound and fetoscopic surveillance was performed, ruling out cord entanglement and, thus, precluding the necessity of transecting the cord. The selective feticide was successfully performed by bipolar coagulation of the umbilical cord of the abnormal fetus under ultrasound guidance. The survivor twin developed normally during the rest of the pregnancy and was born at term. At 6 months of age, the infant was healthy. Selective feticide in complicated monoamniotic pregnancies can be safely performed. Cord entanglement can be confidently excluded by both ultrasound and fetoscopy, thus making the systematic transection of the umbilical cord unnecessary.

Umbilical cord entanglement in monoamniotic twins.

Monochorionic–monoamniotic twin pregnancies are a rare obstetric high-risk situation with an estimated frequency of 1 per 25 000 pregnancies. They occur when the division of the morula into two similar totipotent parts takes place between days 9 and 12 after conception. Perinatal mortality is extremely high, ranging between 28% and 70%1. Fetal mortality is caused by prematurity, cord complications and associated congenital anomalies. These days, with the widespread application of sophisticated first-trimester ultrasound, the detection of monoamniotic twin pregnancies can occur earlier and be more precise. Sonographic criteria include single placenta, absence of separating membrane and concordant sex. However, this improved diagnosis has little impact on the regime of surveillance, management and outcome of such pregnancies. While intensive surveillance of monoamniotic twin pregnancies is generally performed, the right time for and mode of delivery are still under discussion. Delivery by Cesarean section at 32 weeks' gestation is recommended by some groups2 in order to avoid intrauterine complications in late pregnancy. However, whether there is excess mortality after 30–32 weeks is questionable. A recent study by Demaria et al.3 of 19 monoamniotic twin pregnancies documented that there were no double fetal deaths after 26 weeks. Delivery of monoamniotic pregnancies by Cesarean section can also help avoid intrapartum accidents of collision and impaction. However, Demaria et al.3 report a 40% rate of uncomplicated vaginal deliveries. The Picture of the Month (Figure 1a) demonstrates prenatal color Doppler imaging of a monoamniotic twin pregnancy in week 26 showing the two very close cord insertions. Under strict surveillance the pregnancy was successfully continued until week 32. Two healthy newborns were delivered via primary Cesarean section after systematic pulmonary maturation. Part (b) illustrates the large umbilical cord entanglement with a very short section of ‘free’ cord in both twins. In this case a cord accident with a tight clinch and entanglement with impaired umbilical perfusion seems probable if the pregnancy had been prolonged. Furthermore, this situation excludes a normal vaginal delivery. In retrospect, a planned Cesarean section in the 32nd week was justified since both newborns showed a normal neonatal adaptation period. (a) Prenatal color Doppler ultrasound image of a monoamniotic twin pregnancy in week 26 showing the two very close cord insertions. (b) Postnatal photograph showing the large umbilical cord entanglement (black arrows) with a very short section of ‘free’ cord (white arrow) in both twins. Knowing that no optimal protocol for the management of monoamniotic pregnancies has been defined, we believe that sonographic investigation and documentation of the umbilical cord may contribute helpful information to the decision-making process.