Triple pregnancy - etiology and early diagnosis.

OBJECTIVE: To provide an overview of the etiology and early dia-gnosis of triple pregnancy, with emphasis on the possibilities of ultrasound and magnetic resonance (MR) imaging. METHODOLOGY: Processing of data from the available literature on the issue of triple pregnancy. CONCLUSION: Spontaneous triple pregnancy conception is rare. In most cases, it is a concept associated with assisted reproduction methods. Multiple pregnancy is associated with a higher incidence of complications during pregnancy and childbirth, but it also has its own specific complications. Chorionicity and amnionicity of multiple pregnancies are two important parameters in determining the strategy of dispensary care in pregnancy and management of childbirth. The use of ultrasound and MR imaging is crucial for their accurate determination in early pregnancy.

Rare spontaneous monochorionic dizygotic twins: a case report and a systematic review.

BACKGROUND: Monochorionic dizygotic twins are a rare condition, mostly related to assisted reproductive technology. This type of twinning is burdened by the same risk of pregnancy complications found in monochorionic monozygotic pregnancies. CASE PRESENTATION: We report a case of spontaneous monochorionic dizygotic twins sharing situs inversus abdominalis and isolated levocardia, with only one twin affected by biliary atresia with splenic malformation syndrome. We also conducted a literature review of the 14 available documented monochorionic dizygotic twin gestations spontaneously conceived. CONCLUSIONS: It is still unclear how this unusual type of twinning can occur in spontaneous conception. The evidence so far suggest the importance to timely diagnose the chorionicity, in order to adequately manage the typical complications associated with monochorionicity.

Determining chorionicity and amnionicity in twin pregnancies: Pitfalls.

Although the accuracy of chorioamnionicity determination in multiple pregnancy is nearly 100%, some pitfalls do exist. These pitfalls may arise from some confusing sonographic appearance or because of certain rare variations of twinning going against the general principles. Pitfalls in chorionicity determination include (1) the disappearance of the twin peak sign with the regression of chorion frondosum and thinning of the intertwin membrane with advancing gestation; (2) fake twin peak sign because of other structures creeping into the intertwin membrane-placental junction; (3) intrauterine septum or synechia being mistaken as a thick intertwin membrane; (4) bipartite placenta in monochorionic twin being misinterpreted as two separate placentas of dichorionic twin; (5) erroneous fetal sex determination in sex chromosome mosaicism, monogenic disorders, and malformed genitalia in one fetus; and (6) rare twinning types such as dizygotic monochorionic twin and sesquizygotic twin. Pitfalls in amnionicity determination are (1) the lack of correlation between the number of yolk sacs and amnionicity and (2) failure to visualize the intertwin membrane because of technical issues.

ULTRASOUND CHARACTERISTIC OF EMBRYO, FETAL EGG AND CHORIONIC STRUCTURES IN PREGNANT WOMEN WITH MISCARRIAGE.

OBJECTIVE: The aim: The aim of the study was to assess the peculiarities of the formation and development of the fetoplacental system, to study the structures of the embryo, gestational sac, chorion in pregnant women with miscarriage. PATIENTS AND METHODS: Materials and methods: A comprehensive ultrasound examination of 50 pregnant women was carried out in the period from 5 to 16 weeks of pregnancy, of which 25 - with a history of miscarriage (main group), and 25 - with an unremarkable medical history (control group). RESULTS: Results: We have identified the following echographic markers of adverse course and outcome of pregnancy in women with miscarriage in embryonic and early fetal periods:- lag of CRL of an embryo by 2 weeks and more at ultrasound examination in terms up to 9 weeks of gestation;- corporal or basal (near the stem of the embryo body) location of chorionic detachment with the formation of retrochorial hematoma with a volume of more than 25 ml;- pronounced progressive decrease in the volume of the gestational sac and amniotic cavity;- pronounced polyhydramnios with the presence of a coarse echopositive suspension in the amnioticcavity. The likelihood of spontaneous miscarriage and the formation of placental dysfunction is higher with the simultaneous detection of 2 or more echographic markers. CONCLUSION: Conclusions: Ultrasound examination is necessary to assess the echographic parameters of the formation and development of the embryo and extraembryonic structures in the first trimester with a history of miscarriage in order to the subsequent choice of rational tactics of pregnancy management.

Case report: Chorionic bump detected in the third trimester.

A chorionic bump (CB) is a focal irregular bulge in the surrounding choriodecidual due to hematoma. The incidence of CB is between 1.5 and 7 per 1000 pregnancies. The presence of a chorionic bump is associated with a significantly higher risk of adverse perinatal outcomes. CB often decreases in size with time and rarely persists beyond the first trimester. Our case report presents and discusses a chorionic bump diagnosed in the third trimester. To our knowledge, this is the first case of CB to reported in the third trimester.

Comparative evaluation of three different formulas for predicting the parturition date of German Shepherds following somatic cell nuclear transfer.

Several studies have reported methods to estimate the parturition date of dogs using ultrasonographic measurements. However, these prediction models were mainly determined using ultrasonographic measurements of naturally pregnant small- and medium-sized dogs, and no such studies have been performed using dogs carrying cloned fetuses produced via somatic cell nuclear transfer. The present study evaluated the abilities of three reference formulas (Luvoni and Grioni, Milani et al., and Groppetti et al.), all of which were developed using data from naturally occurring pregnancies, to accurately predict the parturition date in surrogates carrying cloned German Shepherd (GS) fetuses. All three formulas were based on the use of inner chorionic cavity diameter (ICC) measurements, obtained via ultrasonography. For evaluation, a total of 54 ICC measurements were collected from 14 pregnant bitches carrying cloned GS fetuses. We found that the clinical accuracy of the breed-specific Groppetti et al. formula was highest among those of the three formulas tested, with 87% and 100% of the estimated parturition dates (calculated based on the ICC measurements) being within 1 and 2 days, respectively, of the actual delivery date. By contrast, the Luvoni and Grioni formula showed relatively low accuracy, and the Milani et al. formula showed higher accuracy than that reported previously for natural pregnancies.

When diamniotic twins suddenly become monoamniotic twins: spontaneous septostomy of the dividing membrane.

In twin pregnancies, amnionicity and chorionicity are crucial as they strongly determine prenatal and perinatal management. First trimester ultrasound allows a highly reliable diagnosis of amnionicity and chorionicity, making it an internationally accepted standard in antenatal care. However, in rare cases, amnionicity can change from diamniotic to monoamniotic throughout pregnancy, substantially impacting perinatal management. We report the case of a confirmed monochorionic diamniotic twin pregnancy with a diagnosis of spontaneous septostomy of the dividing membrane (SSDM) at 28 weeks of gestation, resulting in a pseudomonoamniotic pregnancy. Even though SSDM is a rare condition and its sonographic diagnosis might be challenging, it should be considered if, in a known diamniotic pregnancy, there is a sudden failure to visualise the intertwin membrane truly separating both twins.

Horizontal Guided Bone Regeneration Using a Dehydrated Amnion/Chorion Membrane: A Case Report.

This article describes a novel approach for horizontal guided bone regeneration (GBR) using a dehydrated amnion/chorion membrane (dHACM) in conjunction with a composite mixture of cortical autogenous particulate bone scrapings and mineralized bovine bone particulate in the anterior maxilla, allowing for placement of dental implants in a previously deficient alveolar ridge. The grafted region was reentered 8 months after GBR surgery, and a substantial increase in horizontal bone width was observed. Endosseous dental implants were placed with excellent primary stability in a prosthetically driven manner (which could not have been done prior to GBR) and successfully restored with a screw-retained bridge prosthesis. To the authors' knowledge, this is the first reported documentation of successful horizontal GBR using dHACM with subsequent implant placement and restoration, and the first to demonstrate the excellent clinical potential of this biomaterial.

Intermembrane distances at the feto-maternal interface in epitheliochorial placentation.

INTRODUCTION: In an epitheliochorial placenta, the apical membranes of trophoblast cells and of uterine epithelial cells are in contact to each other (feto-maternal contact). In addition, there are also folds in which the trophoblast membrane is in contact with itself (feto-fetal contact) and areas where apical uterine epithelial membrane is in contact with itself (materno-maternal contact). METHODS: We use transmission electron microscopy of placental samples from pigs. (n = 3), cows (n = 2), sheep (n = 2), goat (n = 2) and roe deer (n = 1) to study the intermembrane distance in these three contact types. RESULTS: The measured intermembrane distances vary between 8 and 25 nm. One common feature is that the distance at feto-fetal contact sites is about 6-10 nm wider than at materno-maternal sites and feto-maternal sites show intermediate values. DISCUSSION: This finding suggests that the membrane distance at feto-maternal contact sites is determined by heterophilic binding of larger fetal to smaller maternal binding molecules. Homophilic binding of smaller maternal or larger fetal molecules lead to the smaller or wider intermembrane distances at materno-maternal or feto-fetal contact sites respectively. The observation that this similar pattern of membrane distances is present in pigs and in ruminants suggest that an evolutionary mechanism is involved in determining the intermembrane distance in epitheliochorial placentas.

Multifetal Gestations: Twin, Triplet, and Higher-Order Multifetal Pregnancies: ACOG Practice Bulletin, Number 231.

The incidence of multifetal gestations in the United States has increased dramatically over the past several decades. For example, the rate of twin births increased 76% between 1980 and 2009, from 18.9 to 33.3 per 1,000 births (1). However, after more than three decades of increases, the twin birth rate declined 4% during 2014-2018 to 32.6 twins per 1,000 total births in 2018 (2). The rate of triplet and higher-order multifetal gestations increased more than 400% during the 1980s and 1990s, peaking at 193.5 per 100,000 births in 1998, followed by a modest decrease to 153.4 per 100,000 births by 2009 (3). The triplet and higher-order multiple birth rate was 93.0 per 100,000 births for 2018, an 8% decline from 2017 (101.6) and a 52% decline from the 1998 peak (193.5) (4). The long-term changes in the incidence of multifetal gestations has been attributed to two main factors: 1) a shift toward an older maternal age at conception, when multifetal gestations are more likely to occur naturally, and 2) an increased use of assisted reproductive technology (ART), which is more likely to result in a multifetal gestation (5). A number of perinatal complications are increased with multiple gestations, including fetal anomalies, preeclampsia, and gestational diabetes. One of the most consequential complications encountered with multifetal gestations is preterm birth and the resultant infant morbidity and mortality. Although multiple interventions have been evaluated in the hope of prolonging these gestations and improving outcomes, none has had a substantial effect. The purpose of this document is to review the issues and complications associated with twin, triplet, and higher-order multifetal gestations and present an evidence-based approach to management.

Performance and Diagnostic Value of Genome-Wide Noninvasive Prenatal Testing in Multiple Gestations.

OBJECTIVE: To evaluate the accuracy and diagnostic value of genome-wide noninvasive prenatal testing (NIPT) for the detection of fetal aneuploidies in multiple gestations, with a focus on dichorionic-diamniotic twin pregnancies. METHODS: We performed a retrospective cohort study including data from pregnant women with a twin or higher-order gestation who underwent genome-wide NIPT at one of the eight Belgian genetic centers between November 1, 2013, and March 1, 2020. Chorionicity and amnionicity were determined by ultrasonography. Follow-up invasive testing was carried out in the event of positive NIPT results. Sensitivity and specificity were calculated for the detection of trisomy 21, 18, and 13 in the dichorionic-diamniotic twin cohort. RESULTS: Unique NIPT analyses were performed for 4,150 pregnant women with a multiple gestation and an additional 767 with vanishing gestations. The failure rate in multiple gestations excluding vanishing gestations ranged from 0% to 11.7% among the different genetic centers. Overall, the failure rate was 4.8%, which could be reduced to 1.2% after single resampling. There were no common fetal trisomies detected among the 86 monochorionic-monoamniotic and 25 triplet cases. Two monochorionic-diamniotic twins had an NIPT result indicative of a trisomy 21, which was confirmed in both fetuses. Among 2,716 dichorionic-diamniotic twin gestations, a sensitivity of 100% (95% CI 74.12-100%) and a specificity of 100% (95% CI 99.86-100%) was reached for trisomy 21 (n=12). For trisomy 18 (n=3), the respective values were 75% (95% CI 30.06-95.44%) sensitivity and 100% (95% CI 99.86-100%) specificity, and for trisomy 13 (n=2), 100% (95% CI 20.65-100%) sensitivity and 99.96% (95% CI 99.79-99.99%) specificity. In the vanishing gestation group, 28 NIPT results were positive for trisomy 21, 18, or 13, with only five confirmed trisomies. CONCLUSION: Genome-wide NIPT performed accurately for detection of aneuploidy in dichorionic-diamniotic twin gestations.

Changes in the Ultrasonographical Appearance of Intertwin-Dividing Membrane of Monochorionic Diamniotic Twin Pregnancy.

Ultrasound determination of chorionicity in the first trimester has a high accuracy, but it is associated with some pitfalls. This report presents changes in ultrasound findings during a monochorionic pregnancy with chorionic membrane folding (CMF). The patient was a 32-year-old woman, gravida 2 para 0. Her transvaginal ultrasonography identified two gestational sacs (GSs) and two embryos at 7 weeks of gestation. At 9 weeks' gestation, an ultrasound image showed a lambda sign at both sides and the interruption of chorionic membranes, resulting in the diagnosis of a monochorionic diamniotic (MCDA) twin pregnancy with CMF. At 11 weeks' gestation, an ultrasound image showed a lambda sign at one portion of the septum and a T sign at another portion. This change suggested that the folded chorionic membrane had partially flattened. At 35 weeks' gestation, an emergency cesarean section was performed. Two healthy male neonates were delivered. Histological placental examination confirmed that the intertwin membrane was composed of two amniotic membranes without a folded chorionic membrane, confirming the diagnosis of a MCDA twin pregnancy. This case presents two important ultrasound chorionicity findings: a monochorionic pregnancy with CMF can show two GSs and a lambda sign and the CMF can flatten or change during the pregnancy.

Lacunar-like changes of the chorion: can it be a first-trimester ultrasound sign in predicting worse clinical outcome in cesarean scar pregnancy termination?

OBJECTIVE: To observe the lacunar-like changes in cesarean scar pregnancy (CSP) ultrasonography in first trimester and to explore its relationship with clinical outcome in early pregnancy termination. METHODS: This is a retrospective case-control study. Patients who were diagnosed as CSP and chose to terminate pregnancy from January 2017 to April 2020 were enrolled. According to occurrence of lacunar-like change in chorion membrane, patients were divided into case and control group. The clinical manifestation, laboratory test, ultrasound data, and outcome were compared. RESULTS: Fifty-five CSP patients were enrolled with 20 (36.4%) in case group and 35 (63.6%) in control group. As for ultrasound features, the maximum outer diameter of gestational mass (5.6 ± 2.5 cm vs. 3.9 ± 1.5 cm), the maximum thickness of the chorion membrane (median number 1.1 cm vs. 0.7 cm), the longitudinal diameter of the implanting part of gestational mass in uterine lower segment (3.3 ± 1.8 cm vs. 1.2 ± 0.5 cm), uterine lower segment protrusion incidence (12, 60% vs. 2, 5.7%), and the crown-rump length of fetus (median number 1.7 cm vs. 0.7 cm) were bigger or higher in case group than that of the control group; the minimum thickness of the uterine lower segment myometrium (median number 0.08 cm vs. 0.20 cm) was significantly thinner in case group. CDFI grading of case group was different from control group with more cases in higher grades. As for clinical outcome, the patients of case group showed more frequency of CSP lesion resection under open surgery or laparoscopy (7, 35% vs. 1, 2.86%) rather than suction curettage, more blood loss in surgery (median number 35 ml vs. 20 ml) and more hospitalization days (median number 7.5 d vs. 3.5 d) than control group. CONCLUSIONS: Lacunar-like change of chorion can be detected in early gestation and may act as a predictor of complicated and worse clinical outcome.

Twin chorionicity and zygosity both vary with maternal age.

Objective: To determine the ratio of dichorionic (DC) to monochorionic (MC) twins by maternal age. Methods: We reviewed all twin pregnancies undergoing first trimester screening (FTS) with nuchal translucency from April 2009 to December 2012 with sonographic determination of chorionicity. Cases were linked to newborn screening (NBS) results and zygosity estimated based on rates of fetal sex discordance. The ratio of DC to MC placentation by maternal age was calculated. Results: We identified 11,351 twin pregnancies with FTS and documented chorionicity. Among these, 7,861 (64.2%) had linked data on FTS and NBS to allow estimation of zygosity based on neonatal sex. Of these, 1,464 (18.6%) were MC and 6,406 (81.4%) DC. The MC twin rate remained constant while the DC twin rate increased with maternal age until 40y. At < 20y, 55% of twin pregnancies were monozygotic (MZ), as compared to 29% at ≥ 40y. Of MZ twins, 38% were DC at < 20y, while 53% were DC at ≥ 40y. Conclusions: Our data suggest a relationship of both zygosity and chorionicity with maternal age. DZ twinning increased with maternal age, while among MZ twins, the proportion that were DC also increased with maternal age.

Prenatal Sonographic Detection of Monochorionic Twins with Bipartite Placenta.

Background Determination of placentation and amnionicity is important for antenatal and intrapartum management in twin gestations. We present an typical monozygotic twin placenta and underscore the sonographic features and diagnostic pitfalls that may interfere with antenatal diagnosis. Case report: A 35-year-old G4P2 with a spontaneous pregnancy applied for routine second trimester anomaly screening. Upon prenatal ultrasonography at 20 weeks, an anatomically normal, same sex twin pregnancy was detected. A thin dividing membrane and a T-sign suggestive of a monochorionic diamniotic pregnancy were visualized. Antenatal follow-up was uneventful. Cesarean delivery was performed at 37 week. Postpartum examination revealed two distinct placental discs connected with each other through membranes. Microscopic examination of the membranes supported monochorionicity. Short Tandem Repeat Profile Analysis revealed identical pattern and confirmed monozygosity. Conclusion: Two separate placentas with a T-sign in same-sex twins should raise the suspicion of monozygosity, and should be followed accordingly.

A cohort study of fetal growth in twin pregnancies by chorionicity: comparison with European and American standards.

OBJECTIVE: To develop fetal growth standards for twin gestations by placental chorionicity in a Spanish population and compare them with European and American standards to estimate the suitability of their use in clinical practice. STUDY DESIGN: This was a retrospective cohort study of 518 twin pregnancies, 435 dichorionic-diamniotic and 83 monochorionic-diamniotic, performed between January 2012 and December 2017. A total of 4,783 and 1,455 estimated fetal weights were considered from the 17th to the 37th week of gestation, using multilevel models, to build dichorionic-diamniotic and monochorionic-diamniotic standards, respectively. The percentages of small and large for gestational age were calculated as a model adjustment measure and adjustment to the studied data and the values provided by our model were compared against those of six European and American twin standards and three singleton standards. Correlation analyses between percentile predictions were performed using Cohen kappa coefficient. The predictive ability to detect small for gestational age was also provided by the sensitivity and positive predictive value. RESULTS: We found slight differences between standards by chorionicity, being dichorionic-diamniotic percentiles slightly higher than monochorionic-diamniotic ones from the 17th to 37th weeks' gestation. For dichorionic-diamniotic cases, both our standard (9.8-8.2) and that of Grantz (8.2-10.5) showed good adjustments for the 10th and 90th percentiles while the other compared standards underestimated or overestimated them. For monochorionic-diamniotic cases, both our standard (10.2-8.5) and that of Shivkumar (11.4-6.8) had the most suitable adjustment. The correlation analysis between small and large for gestational age cases provided by standards, showed clear differences among them. Kappa's coefficient showed a substantial agreement between both Ananth (0.7) and Stirrup (0.69) dichorionic-diamniotic cases and our standard. There was also a substantial agreement between the Shivkumar (0.77) standard and our results for monochorionic-diamniotic cases. The correlation was moderate for all other comparisons. CONCLUSIONS: Our model showed a good adjustment to the studied population. There are clear differences among small and large for gestational age cases provided by twin standards in our studied population. The twin growth standards depend on the population characteristics and model structure. We found the use of singleton standards for twin pregnancies inadequate.

Amnion-Chorion Allograft Barrier Used on Root Surface for Regenerative Procedures: Case Report.

INTRODUCTION: Guided tissue regeneration (GTR) has been well documented with combination of bone graft substitutes and biologic modifiers to improve the outcomes of periodontal regenerative procedures. Amnion-chorion allograft membrane (ACM) is a placenta-derived resorbable allograft membrane which contains growth factors found in the placenta. The primary purpose of the barrier membranes for GTR was to exclude the epithelial down-growth along with the root surface, however, the ACM can be used as an additional biologic modifier because of the release of growth factors from the ACM after placement. The aim of this case report is to evaluate the efficacy and the application of ACM on the previously diseased root surface to treat periodontal intrabony defect. CASE PRESENTATION: A 60-year-old Caucasian male with deep and wide intrabony defect on mesial #19 was treated with a regenerative procedure with combination of application of ACM on the root surface and filling the intrabony defect with the corticocancellous freeze-dried bone allograft. The bone substitute was covered with another layer of ACM and primary closure was achieved. Wound healing process was uneventful, and the clinical and radiographic outcomes were favorable up to 18 months after the surgical procedure. CONCLUSION: This case report demonstrated that the application of ACM on the root surface with a combination of bone substitute might enhance to the radiographic bone fill and the clinical attachment level gain and minimize the risk of post-operative gingival recession.