Cervical length as a screening tool for preterm birth in twin pregnancies: a systematic review and critical evaluation of quality clinical practice guidelines.

OBJECTIVES: Twin pregnancies are at increased risk of preterm birth (PTB) compared to singletons. Evaluation of cervical length (CL) represents the optimal tool to screen PTB in singleton. Conversely, there is less evidence on the use of CL in twins. Our aim was to evaluate the methodological quality and clinical heterogeneity of clinical practice guidelines (CPGs) on the CL application in twins using AGREE II methodology. METHODS: MEDLINE, Scopus, and websites of the main scientific societies were examined. The following aspects were evaluated: diagnostic accuracy of CL, optimal gestational age at assessment and interventions in twin pregnancies with reduced CL. The quality of the published CPGs was carried out using "The Appraisal of Guidelines for REsearch and Evaluation (AGREE II)" tool. The quality of guideline was rated using a scoring system. Each considered item was evaluated by the reviewers on a seven-point scale that ranges from 1 (strongly disagree) to 7 (strongly agree). A cut-off >60 % identifies a CPGs as recommended. RESULTS: The AGREE II standardized domain scores for the first overall assessment had a mean of 74 %. The score was more than 60 % in the 66.6 % of CPGs analyzed indicating an agreement between the reviewers on recommending the use of these CPGs. A significant heterogeneity was found; there was no specific recommendation on CL assessment in about half of the published CPGs. There was also significant heterogeneity on the CL cut-off to prompt intervention. CONCLUSIONS: Despite the fact that the AGREE II analysis showed that the majority of the included guidelines are of good quality, there was a significant heterogeneity among CPGs as regard as the indication, timing, and cut-off of CL in twins as well as in the indication of interventions.

Guideline No. 428: Management of Dichorionic Twin Pregnancies.

OBJECTIVE: To review evidence-based recommendations for the management of dichorionic twin pregnancies. TARGET POPULATION: Pregnant women with a dichorionic twin pregnancy. BENEFITS, HARMS, AND COSTS: Implementation of the recommendations in this guideline may improve the management of twin pregnancies and reduce neonatal and maternal morbidity and mortality. EVIDENCE: Published literature was retrieved through searches of PubMed and the Cochrane Library using appropriate controlled vocabulary (e.g., twin, preterm birth). Results were restricted to systematic reviews, randomized controlled trials, controlled clinical trials, and observational studies. There were no date limits, but results were limited to English- or French-language materials. VALIDATION METHODS: The content and recommendations were drafted and agreed upon by the principal authors. The Board of the SOGC approved the final draft for publication. The authors rated the quality of evidence and strength of recommendations using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. See online Appendix A (Tables A1 for definitions and A2 for interpretations of strong and weak recommendations). INTENDED AUDIENCE: Obstetricians, family physicians, nurses, midwives, maternal-fetal medicine specialists, radiologists, and other health care providers who care for women with twin pregnancies. SUMMARY STATEMENTS: RECOMMENDATIONS.

Portal venous gas by ultrasound in advance of impending necrotizing enterocolitis of a very low birth weight infant.

Necrotizing enterocolitis (NEC) is a serious complication of premature infants, portal venous gas (PVG) under X-ray, and ultrasound is a typical manifestation of this disease. We report a case of a very low birth weight (VLBW) infant with PVG unexpectedly detected by ultrasound before the onset of NEC. After positive ultrasound result, clinical manifestations, X-ray, and lab tests confirmed the diagnosis of NEC. This is the first report of a similar case, demonstrating the value of ultrasonography in prediction or early diagnosis of NEC, which may change our understanding of the disease and the timing of examination.

Beware the Innocent Presentation of a Spontaneous Perforated Meckel Diverticulum: A Rare Case and Review of the Literature.

Perforation of a Meckel diverticulum in a preterm neonate is very rare. To our knowledge, only 7 cases of spontaneous Meckel perforation in a preterm neonate have previously been described in the literature. The etiology is uncertain. We present the case of a 30-week preterm female twin with a spontaneous Meckel diverticulum perforation discovered on day 3 of life and review the published cases. A possible etiological explanation for this rare entity at this age group is also suggested.

[Transcervical Embryoscopy after Missed Abortion in Monoamniotic Twins with Discordant Exencephaly]. / Transzervikale Embryoskopie nach verhaltenem Abort in monoamnioten Zwillingen mit diskordanter Exenzephalie.

INTRODUCTION: Monoamniotic twins are considered a cause of high-risk pregnancies. Thereby, discordant malformations do occur rarely. A discordant exencephaly has been described in only a few cases. Transcervical embryoscopy can be performed in cases of monoamniotic twins with missed abortion directly before the abort-curettage. CASE REPORT: The case of a 35-year-old G1/P0 women in the 12(th) week of pregnancy is described. She had a monoamniotic twin pregnancy with discordant exencephaly and missed abortion diagnosed at 11+2 weeks. A transcervical embryoscopy was performed immediately before the abort-curettage and identified the discordant exencephaly and an additional umbilical cord knot of the 2 foetuses as a probable cause for the abortion. DISCUSSION: The transcervical embryoscopy lead in our case report to the diagnosis of a umbilical cord knot in a monoamniotic twin pregnancy with missed abortion. We also identified a discordant exencephaly by embryoscopy. With blunt access to the amniotic cavity, the transcervical embryoscopy applies only a minor additional risk to the abort-curettage. However, it should only be performed when the patient explicitly asks for enhanced diagnostics. CONCLUSION: Transcervical embryoscopy can be performed as an additional diagnostic tool in cases of monoamniotic twins with missed abortion. However, a detailed risk-benefit analysis should be done upfront in consultation with the patient.

[Effect on maternal blood dilution of fetoscopic laser occlusion of chorioangiopagous vessels in treating twin to twin transfusion syndrome].

OBJECTIVE: To evaluate the effect on maternal blood dilution of fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) in treating twin to twin transfusion syndrome (TTTS). METHODS: The clinical data of 71 cases of TTTS who had FLOC in Peking University Third Hospital were reviewed. Fluid intake, blood pressure, heart rate, red blood cell count, hemoglobin and hematocrit in perioperative 24 hours were analyzed. RESULTS: (1) According to the Quintero staging, 9 cases were stage Ⅰ, 24 were stage Ⅱ, 28 were stage Ⅲ and 10 cases were stage Ⅳ. (2) The average operation time of FLOC was (64.0±16.3) minutes. One case had placental abruption after the procedure; one had placental vessel rupture and 6 women refused to take blood counting. These 8 cases were excluded and 63 cases were included in the study. (3) The perioperative bleeding volume was 3 (1, 5) ml, and the volume of fluid intake, urine, amniotic fluid drainage and net fluid intake in the perioperative 24 hours was 2 050 ml(1 530 ml, 3 700 ml), 2 300 ml (1 100 ml, 3 500 ml), 1 900 ml (1 400 ml, 2 700 ml) and -1 760 ml (-100 ml, -3 350 ml), respectively. There was no significant difference between maternal blood pressure or heart rate preoperatively and postoperatively. (4) The maternal red blood cell count [(3.47±0.36)×10(12)/L versus (3.01± 0.37)×10(12)/L, P=0.000], hemoglobin [(107.8±12.1) g/L versus (95.1±11.2) g/L, P=0.000] and hematocrit [0.313(0.238, 0.387) versus 0.276(0.213, 0.800), P=0.000] decreased significantly 24 hours after FLOC. (5) The postoperative hematocrit decreased more in the group which the amniotic fluid drainage volume was 2 000-3 000 ml than that in the group which the amniotic fluid drainage volume was 1 000-1 999 ml. CONCLUSIONS: The blood dilution can not be ignored after the FLOC in TTTS patients. The more the amniodrainage volume during the FLOC, the more the maternal blood dilution would be. It might result from amniodrainage during the FLOC, improved maternal-placenta circulation and tocolytics used after FLOC. More attention should be take about maternal cardiac function and complications related with anemia after FLOC.

[Asynchronous twin births. Case report and obstetric management review]. / Parto gemelar asincrónico. Presentación de un caso y revisión del tratamiento obstétrico.

BACKGROUND: The incidence of multiple pregnancy has increased in the last years. These pregnancies are associated with more obstetric complications regarding single pregnancies, one of the most important is prematurity. In extremely rare cases premature delivery of one fetus may occur, being retained in the uterine cavity the second fetus until birth later, producing the so-called delayed delivery of twins. CASE REPORT: We report the case of a double twin pregnancy with delayed delivery of the second fetus after birth of the first one within 22.6 weeks of gestation and the second one birth at at 24 weeks of gestation, eight days later after the first one. A review of cases published in the literature is performed and the obstetric management of delayed delivery discussed.

Twin Reversed Arterial Perfusion (TRAP) Sequence: A Case Report and Review of Treatment.

A cardiac twin or twin reversed arterial perfusion (TRAP) sequence is a rare unique complication of monozygotic multiple pregnancy. In this disorder, there is a normally formed donor (the pump twin) who has features of congestive heart failure (CHF) as well as a recipient (the acardiac twin) who lacks a well-defined a heart structure. Also evident are other structures, namely the TRAP sequencefrom pump to acardiacfetus via single artery-to-artery and vein-to-vein anastomoses directly between the two cords or indirectly on the chorionic plate. Overall, the perinatal mortality rate for the pump twin is 35-55%. Prenatal diagnosis and prognosis factors can be examined through ultrasound. The optimal management of a cardiac twin pregnancies is controversial. The expected treatment of acardiac anomaly presently relies on maximizing the chance ofterm delivery and preventing CHF in the healthy pump twin or interrupting vascularization between the two twins. This article reported the experience of acardiac twin management in Thammasat University Hospital and reviewed the current knowledge ofthe condition, prenatal diagnosis, prognosis factor and management options focusing on conservative management compared to invasive treatment.

Netherton syndrome associated with growth hormone deficiency.

Netherton syndrome (NS) is a rare autosomal recessive disorder characterized by ichthyosiform scaling, hair abnormalities, and variable atopic features. Mutations in the serine protease inhibitor Kazal type 5 (SPINK5) gene leading to lymphoepithelial Kazal-type-related inhibitor (LEKTI) deficiency cause NS. Growth retardation is a classic feature of NS, but growth hormone (GH) deficiency with subsequent response to GH therapy is not documented in the literature. It is proposed that a lack of inhibition of proteases due to a deficiency of LEKTI in the pituitary gland leads to the overprocessing of human GH in NS. Herein we report three patients with NS who had growth retardation associated with GH deficiency and responded well to GH therapy.

[Clinical management and perinatal outcome of twin reversed arterial perfusion sequence in different stage].

OBJECTIVE: To discuss the methods and outcomes of twin reversed arterial perfusion sequence in different stage. METHODS: From August 2012 to December 2013, 11 cases were diagnosed with twin reversed arterial perfusion sequence (TRAP) by 3d color Doppler ultrasound in the Maternal ang Fetal Medicine Center, Affiliated Shengjing Hospital, China Medical University, including 3 cases in stage I a, 7 in stage II a and 1 case in stage II b. We performed expected therapy to 3 cases in stage I a and 4 cases in stage II a [1 case (case 9) in stage II a developed to stage II b and was terminated by emergency cesarean section], radio frequency ablation (RFA) selective reduction to 3 cases in stage II a, emergency cesarean section to 1 case in stage II b. All cases except case 1, 4 took cesarean section to terminate pregnancy and would be followed up on the aspect of infant's growth. RESULTS: (1) 3 cases in stage I a were monitored by sequential ultrasound examination, all donors grew normally, in which 2 acardias arised spontaneous cessation of flow and were implemented of cesarean section after the normal period of gestation; 1 case suffered premature rupture of membrane and experienced the natural childbirth at 34 gestation weeks plus 5 days. The survived average labor weight was 2 923 g. (2) In the 7 stage II a cases, 3 cases were implemented of RFA selective reduction, 2 cases survived and the average labor gestation was 35 weeks plus 1 day and average labor weight was 2 050 g; in 3 expected therapy cases, 1 case suffered premature rupture of membrane at 34 gestation weeks plus 5 days and experienced cesarean section; 1 case was observed for 3 weeks and the donor was stillborn; 1 case progressed to stage II b and experienced cesarean section at 34 gestation weeks plus 5 days; and 1 case was lost of follow up. (3) For 2 cases of stage II b cases, one was progressed from stage II a during expected therapy; the other one had been already in stage II b since visiting and experimented an emergency cesarean section, but the neonate died of heart failure two days after labor. (4) 7 survived neonates were followed up, all had a normal condition compared to kids of the same age, except one suffering a congenital heart disease, patent ductus arteriosus and atrial septal defect and whose weight (6 kg at 7 months) was lighter. CONCLUSIONS: We should make the diagnosis of TRAP as early as soon and choose appropriate therapy according to the stage. According to our research, cases in stage I a can undergo an expected therapy under a sequential ultrasound examination; cases in stage II a can undergo a RFA selective reduction to improve the prognosis of the donor, which can make a good perinatal outcome.

A qualitative investigation of experiences of breastfeeding twins and multiples.

BACKGROUND: Research has found that twins and multiples are less likely to be breastfed than singleton babies. Exploration of the experience of breastfeeding twins and multiples from parents' perspectives is limited, and we know little about the experiences of those who breastfeed twins and multiples and the possible barriers they face. AIM: The aim of the research was to explore experiences of breastfeeding twins and multiples in the UK from the perspective of birthing parents. METHODS: A qualitative online survey was carried out (n = 94), followed by online semi-structured interviews (n = 18). The data were analysed using reflexive thematic analysis. FINDINGS: Four themes were developed from the data: (1) "It's one of the things I'm most proud of in my life" (2) The importance of support: "it definitely takes a village with twins" (3) Barriers and the pressure to formula feed: "all they wanted to do was stuff 'em full of formula" and (4) The dynamic experience of breastfeeding twins. DISCUSSION: Many of the participants were able to feed their babies in part due to sheer determination and the refusal to give up when met with challenges. Breastfeeding was an important part of their identity as a mother, however mental health was often impacted by their experiences, as well as the challenges they faced when seeking support. CONCLUSION: Breastfeeding twins and multiples is a challenging yet rewarding experience. Our findings indicate that further training and support is needed to enable healthcare providers to support parents of twins on their breastfeeding journey.

Single fetal death in twin gestations.

Twin pregnancies are at higher risk for fetal mortality when compared with singleton pregnancies. Single fetal demise occurs in 3.7 ­ 6.8 % of all twin pregnancies and considerably increases the complication rate in the co-twin including fetal loss, premature delivery, and end-organ damage. In this review, we summarize the current information on the etiology of single twin demise, the pathophysiology of injury to the surviving twin, and the preventive and secondary management strategies.

Antenatal Corticosteroids and Neonatal Outcomes in Twins: A Systematic Review and Meta-analysis.

OBJECTIVE: To assess whether antenatal corticosteroid treatment is associated with improved neonatal outcomes in twins. DATA SOURCES: We searched MEDLINE, PubMed, EMBASE, and the Cochrane Library, from inception through August 12, 2021. We did not search ClinicalTrials.gov because our inclusion criteria were restricted to nonrandomized studies. METHODS OF STUDY SELECTION: Records (n=7,802) were screened in Rayyan by two independent reviewers. We included all nonrandomized studies that compared antenatal corticosteroid treatment with no treatment in twins. Our outcomes of interest were neonatal mortality, respiratory distress syndrome (RDS), intraventricular hemorrhage, bronchopulmonary dysplasia, necrotizing enterocolitis, periventricular leukomalacia, and retinopathy of prematurity. TABULATION, INTEGRATION, AND RESULTS: We used the ROBINS-I tool (Risk Of Bias In Non-randomised Studies - of Interventions) to assess risk of bias. We performed random-effects meta-analyses of estimates from studies without critical risk of bias due to confounding, and reported summary adjusted odds ratios (aORs) and 95% CIs. Eighteen cohort studies (that reported on 33,152 neonates) met inclusion criteria. Sixteen studies restricted to preterm gestational ages, and 11 defined exposed neonates based on an optimal corticosteroid administration-to-birth interval. Limitations due to confounding and selection bias were common concerns for the risk-of-bias assessments (n=14 at critical or higher), and 11 studies did not account for clustering within twin pairs in their analyses. All included studies had at least moderate risk of bias. Meta-analysis showed that antenatal corticosteroid administration was associated with lower odds of neonatal mortality (aOR 0.59, 95% CI 0.43-0.80, I2 69%, five studies, 20,312 neonates) and RDS (aOR 0.70, 95% CI 0.57-0.86, I2 67%, seven studies, 20,628 neonates) in twins. Results were inconclusive for the other outcomes. CONCLUSION: Evidence from nonrandomized studies suggests antenatal corticosteroids are associated with lower incidence of neonatal mortality and RDS in twins. SYSTEMATIC REVIEW REGISTRATION: PROSPERO, CRD42020205302.

Delayed delivery of a twin pregnancy and uterine atony: morphological and clinical evidence.

This report presents the uncommon case of a 154-day delayed delivery in a spontaneous twin pregnancy associated with uterine atony. After abortion of the first fetus at 16 weeks, a healthy male was born at 38 weeks. Postpartum hemorrhage due to uterine atony, which was successfully treated with prostaglandins, occurred.

Ultrasound in twin pregnancies.

OBJECTIVE: To review the literature with respect to the use of diagnostic ultrasound in the management of twin pregnancies. To make recommendations for the best use of ultrasound in twin pregnancies. OUTCOMES: Reduction in perinatal mortality and morbidity and short- and long-term neonatal morbidity in twin pregnancies. Optimization of ultrasound use in twin pregnancies. EVIDENCE: Published literature was retrieved through searches of PubMed and the Cochrane Library in 2008 and 2009 using appropriate controlled vocabulary (e.g., twin, ultrasound, cervix, prematurity) and key words (e.g., acardiac, twin, reversed arterial perfusion, twin-to-twin transfusion syndrome, amniotic fluid). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies. There were no date restrictions. Studies were restricted to those with available English or French abstracts or text. Searches were updated on a regular basis and incorporated into the guideline to September 2009. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology assessment-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies. VALUES: The evidence collected was reviewed by the Diagnostic Imaging Committee of the Society of Obstetricians and Gynaecologists of Canada, with input from members of the Maternal Fetal Medicine Committee and the Genetics Committee of the SOGC. The recommendations were made according to the guidelines developed by The Canadian Task Force on Preventive Health Care (Table 1). BENEFITS, HARMS, AND COSTS: The benefit expected from this guideline is facilitation and optimization of the use of ultrasound in twin pregnancy. SUMMARY STATEMENTS: 1. There are insufficient data to make recommendations on repeat anatomical assessments in twin pregnancies. Therefore, a complete anatomical survey at each scan may not be needed following a complete and normal assessment. (III) 2. There are insufficient data to recommend a routine preterm labour surveillance protocol in terms of frequency, timing, and optimal cervical length thresholds. (II-2) 3. Singleton growth curves currently provide the best predictors of adverse outcome in twins and may be used for evaluating growth abnormalities. (III) 4. It is suggested that growth discordance be defined using either a difference (20 mm) in absolute measurement in abdominal circumference or a difference of 20% in ultrasound-derived estimated fetal weight. (II-2) 5. Although there is insufficient evidence to recommend a specific schedule for ultrasound assessment of twin gestation, most experts recommend serial ultrasound assessment every 2 to 3 weeks, starting at 16 weeks of gestation for monochorionic pregnancies and every 3 to 4 weeks, starting from the anatomy scan (18 to 22 weeks) for dichorionic pregnancies. (II-1) 6. Umbilical artery Doppler may be useful in the surveillance of twin gestations when there are complications involving the placental circulation or fetal hemodynamic physiology. (II-2) 7. Although many methods of evaluating the level of amniotic fluid in twins (deepest vertical pocket, single pocket, amniotic fluid index) have been described, there is not enough evidence to suggest that one method is more predictive than the others of adverse pregnancy outcome. (II-3) 8. Referral to an appropriate high-risk pregnancy centre is indicated when complications unique to twins are suspected on ultrasound. (II-2) These complications include: 1. Twin-to-twin transfusion syndrome 2. Monoamniotic twins gestation 3. Conjoined twins 4. Twin reversed arterial perfusion sequence 5. Single fetal death in the second or third trimester 6. Growth discordance in monochorionic twins. Recommendations 1. All patients who are suspected to have a twin pregnancy on first trimester physical examination or who are at risk (e.g., pregnancies resulting from assisted reproductive technologies) should have first trimester ultrasound performed. (II-2A) 2. Every attempt should be made to determine and report amnionicity and chorionicity when a twin pregnancy is identified. (II-2A) 3. Although the accuracy in confirmation of gestational age at the first and second trimester is comparable, dating should be done with first trimester ultrasound. (II-2A) 4. Beyond the first trimester, it is suggested that a combination of parameters rather than a single parameter should be used to confirm gestational age. (II-2C) 5. When twin pregnancy is the result of in vitro fertilization, accurate determination of gestational age should be made from the date of embryo transfer. (II-1A) 6. There is insufficient evidence to make a recommendation of which fetus (when discordant for size) to use to date a twin pregnancy. However, to avoid missing a situation of early intrauterine growth restriction in one twin, most experts agree that the clinician may consider dating pregnancy using the larger fetus. (III-C) 7. In twin pregnancies, aneuploidy screening using nuchal transluscency measurements should be offered. (II-2B) 8. Detailed ultrasound examination to screen for fetal anomalies should be offered, preferably between 18 and 22 weeks' gestation, in all twin pregnancies. (II-2B) 9. When ultrasound is used to screen for preterm birth in a twin gestation, endovaginal ultrasound measurement of the cervical length should be performed. (II-2A) 10. Increased fetal surveillance should be considered when there is either growth restriction diagnosed in one twin or significant growth discordance. (II-2A) 11. Umbilical artery Doppler should not be routinely offered in uncomplicated twin pregnancies. (I-E) 12. For defining oligohydramnios and polyhydramnios, the ultrasonographer should use the deepest vertical pocket in either sac: oligohydramnios when < 2 cm and polyhydramnios when > 8 cm. (II-2B).