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 stageⅠ, 24 were stageⅡ,28 were stageⅢand 10 cases were stageⅣ.(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)×1012/L versus (3.01± 0.37) × 1012/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.

Objective To compare the outcomes of selective feticide by umbilical cord ligation (UCL),bipolar cord coagulation (BCC) and radiofrequency ablation (RFA) in the treatment of complicated monochorionic twins.Methods We retrospectively analyzed all cases of complicated monochorionic twin pregnancies treated at Peking University Third Hospital from August 2008 to December 2014.The indications for surgery included severe twin-to-twin transfusion syndrome (TTTS),selective intrauterine growth restriction (sIUGR) (type Ⅱ and Ⅲ),twin reversed arterial perfusion sequence (TRAP) or discordant anomaly.One-way ANOVA,LSD t test,Mann-Whitney U test,Chi-square or Fisher's exact test were used for statistical analysis.Results (1) A total of 68 patients chose selective feticide by different techniques,including fetoscopic UCL (n=18,UCL group) and ultrasound-guided RFA (n=46,RFA group).The other four patients treated by bipolar cord coagulation (BCC) were excluded.The maternal age,proportion of assisted reproductive technology,indications,gestational age and mean birth weight all showed no differences between the two groups (P＞0.05).One case of anterior placenta was found in UCL group,fewer than in the RFA group (27 cases,36.9％)(x2=4.853).No fetal loss occurred within two weeks in UCL group,but there were seven cases (seven cases,15.2％) of earlier fetal loss in RFA group (x2=4.952).The median operation time was (63.2±22.5) min in UCL group,and longer than in the RFA group (33.3 ± 11.4) min (t=5.165),all P＜0.05.(2) The gestational age of TTTS and TRAP patients for feticide was older than patients with sIUGR and discordant anomaly [(22.7± 3.0),(22.8±3.2),(20.3 ± 2.5) and (20.4± 3.6) weeks,respectively,F=2.957,P=0.040].Fetal loss rate within two weeks in patients with discordant anomaly was higher than in other groups (4/11 vs 1/10,0/23 and 1/15,P＜0.05).The survival rate,gestational age at delivery and mean birth weight showed no significant differences among the four groups.(3)Compared with feticided fetuses at the upper uterine cavity,the fetal loss rate was higher,and the operation time,gestational age at delivery,birth weight and neonatal survival rate were lower than those performed at the lower uterine cavity,but the difference was not significant.Conclusions RFA provides similar outcomes of selective feticide in complicated monochorionic twins compared with UCL,while RFA is easier to operate.

Objective To investigate the clinical outcome and placental characteristics of spontaneous twin anemia-polycythemia sequence (sTAPS). Methods Twelve cases with sTAPS delivered in Peking University Third Hospital from May 2013 to August 2016. The data of ultrasound characteristics, gestational age at delivery, and 1 minute Apgar score were analyzed,retrospectively. Placental superficial vascular anastomoses, placental territory discordance and the ratio of umbilical cords insertion distance to the longest placental diameter were also analyzed. Results (1) Only 1 case of sTAPS was diagnosed prenatally, the others were diagnosed postnatally because the fetal middle cerebral artery(MCA) doppler was not measured regularly. Five cases were complicated with selective intrauterine growth restriction (sIUGR). The median gestational age at delivery was 32.8 weeks(31-37 weeks). The pregnancies were terminated because 3 cases were sIUGR typeⅠ, 1 case was sIUGR type Ⅱ, 1 case was sIUGR type Ⅲ, 2 cases were fetal distress, 2 cases were severe pre-eclampsia, 2 cases were premature rupture of membrane, 1 case was fetal hydrops with abnormal doppler waveforms of ductus venouses. (2) When 5 sIUGR cases were excluded, there was no difference between the twins in birth weight [1797 g(940-2620 g),1648 g(980-2500 g);P=0.688]. The hemoglobin (Hb) level in all donor was significantly lower than recipient(P=0.000)and the inter-twin Hb difference was 147.6 g/L (84.0-216.0 g/L). While the reticulocyte percentage in donor was significantly higher than recipient (P=0.013) and reticulocyte percentage ratio was 3.60 (1.04-7.50). Five donor newborns had neonatal asphyxia, including 1 severe asphyxia, while no asphyxia happened in the recipient twins. (3) Arterio-arterial (A-A) anastomoses, veno-venous (V-V) anastomoses, arterio-venous (A-V) anastomoses were found in 3, 1 and 11 placentas, respectively. The total number of anastomoses was 2 (1-5) and the total diameter was 1.1 mm (0.4-2.1 mm), including 0 (0-1) A-A anastomoses with 0.2 mm (0.0-0.9 mm) in diameter and 2 (0-5) A-V anastomoses with 0.7 mm (0.0-2.1 mm) in diameter. The placental territory discordance was 0.17 (0.02-0.40) and the ratio of umbilical cords insertion to the longest placental diameter was 0.82 (0.34-0.99). Conclusions The pathogenesis of sTAPS might result from slow and chronic blood transfusion from donor to recipient through a few minuscule vascular anastomoses in the placenta. In all monochorionic twins, especially sIUGR cases, MCA doppler should be monitored closely in the second and third trimester, in order to diagnose and manage sTAPS in time.

Objective To study the clinical effect of fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) in treating twin to twin transfusion syndrome.Methods The clinical data of 44 consecutive cases of twin to twin transfusion syndrome (TTTS) who had FLOC in the Department of Obstetrics and Gynaecology of Peking University Third Hospital were reviewed and analyzed for perioperative complications,perinatal outcomes and fetal survival rate.Results (1) Patient characteristics:the mean maternal age was (29±4) years,the median gestational age at TTFS being primarily diagnosed was 20.4 weeks,the median gestational age at FLOC was 21.2 weeks.According to the Quintero staging system,there were 9 cases had stages progressed before the operation.(2) FLOC parameter and intraoperative complications:44 cases all could tolerate the operation; there was 1 case of placenta vascular rupture in the operation,no fetal body injury by laser or placental abruption.3 cases underwent cervical cerclage following FLOC.The average operation time of 41 cases alone with FLOC was (60.1± 15.1) minutes.(3) Postoperative complications:the rate of intrauterine fetal death was 15％ (13/88),the rate of intrauterine growth restriction after FLOC was 5％ (4/88),the rate of membranes rupture less than 28 weeks was 16％ (7/44),the rate of TAPS after FLOC was 5％ (2/44),the rate of membrane sepration after FLOC was 5％ (2/44).(4) Perinatal outcome and survival rate:there were 25 patients after FLOC had delivered in the perinatal period.The average gestational age of delivery was (33.5±2.7) weeks.The donor fetuses survival rate was 88％ (22/25),the recipient fetuses survival rate was 100％ (25/25).The birth weight of donor fetuses was significantly less than that of recipient fetuses (1 631g vs 2 071 g,P=0.016).From Quintero staging Ⅰ to Ⅳ,the rate that 44 cases of TTTS had entered the perinatal period was 4/7,11/14,7/19,3/4; both twins survival rates were 4/7,10/14,5/19,3/4; all the fetal survival rate was 8/14,75％ (21/28),32％ (12/38),6/8,respectively.(5) Compared the early stage (Ⅰ + Ⅱ) with the advanced stage (Ⅲ + Ⅳ),the rates that 44 cases of TTTS had entered the perinatal period (71％ vs 44％) and that both twins survived (67％ vs 35％) had no statistically significance.The rate that all the fetus survived in the early stage was significantly (69％ vs 39％) more than that in the advanced stage.(6) All the cases of neoborn were followed up till 1 month postpartum,the donor fetuses and the recipient fetuses had 12 and 5 cases of cardiac abnormalities respectively,each had 1 case of neonatal death and 2 cases of neonatal white matter damage.Conclusions FLOC for TTTS is associated with a better survival rate.Quintero staging probably does not effectively predict the fetal diagnosis of TTTS after FLOC.When TTTS diagnosed,the sooner FLOC given,the better fetal prognosis had.

Objective To evaluate the placental characteristics in monochorionic (MC) twin pregnancy with selective fetal growth restriction (sFGR). Methods Fifty-five placentas from women with MC twin pregnancy were included, who had terminated pregnancy in the Peking University Third Hospital between June 1, 2013 and June 1, 2014, including 23 cases with sFGR and 32 uncomplicated cases as control group. We perfused the placentas within 24 h after delivery, and pigment of four different colors was used to perfuse the umbilical arteries and veins of both twins and determine the types of vascular anastomosis. Umbilical cord insertion, placental territory discordance (PTD, the territory difference between two placentas/the bigger one), and the type, number and diameter of placental superficial vascular anastomosis were analyzed using two independent samples t-test, nonparametric test,χ2 test or Fisher's exact test. Results The PTD was 0.60(0.10-0.80) vs 0.22(0.00-0.90) in sFGR group and control group (Z=-3.913) respectively, and the proportion of placenta with uneven share was 91.3%(21/23) vs 50.0%(16/32) (Fisher's exact test), which were significantly higher in sFGR group (both P < 0.01). The proportion of non-central cord insertion was 82.6% (19/23), 13.0% (3/23) and 40.6% (26/64), respectively, in smaller fetus of sFGR, bigger fetus of sFGR and control group, which was significantly higher in smaller fetus of sFGR than in the other two groups (Fisher's exact test, both P < 0.01). The proportion of arterioarterial (AA), arteriovenous (AV) and venovenous (VV) anastomosis in sFGR group and control group was 78.3%(18/23) vs 75.0%(24/32), 82.6%(19/23) vs 71.9%(23/32), and 17.4%(4/23) vs 15.6%(5/32);there were no significant differences between two groups (Fisher's exact test,all P>0.05). The number of AA, AV and VV anastomosis in sFGR group and control group was 1.0 (0.0-2.0) vs 1.0 (0.0-4.0), 3.0 (0.0-10.0) vs 2.0 (0.0-5.0), and 0.0 (0.0-1.0) vs 0.0 (0.0-3.0) (Z=-0.256, -0.142 and -0.123);the total diameter of AA, AV and VV anastomosis was 2.7 (0.0-7.0) vs 2.2 (0.0-9.7), 4.0 (0.0-13.7) vs 3.4 (0.0-11.5), and 0.0 (0.0-7.9) vs 0.0 (0.0-7.1) mm (Z=-0.070, -0.087 and -0.087);there were no significant differences between two groups (all P>0.05). The total number of all anastomosis was 3.5 (0.0-10.0) vs 3.5 (0.0-6.0) (Z= - 0.567); the total diameter of all anastomosis was 6.9 (0.0-22.4) vs 5.9 (0.0-17.1) mm (Z= - 0.556); there were no significant differences between two groups (all P>0.05). Conclusions Placental sharing discordance and non-central cord insertion may be the risk factors for MC pregnancies complicated with sFGR.

Objective To evaluate the clinical effect and safety of umbilical cord ligation in the fetocide of complicated monochorionic multiple gestations.Methods From January 2009 to December 2012,clinical data of 18 women with complicated monochorionic multiple gestations who experienced intrauterine percutaneous umbilical cord ligation in Peking University Third Hospital were collected.Among the patients,6 were selective intrauterine growth restriction (1 with type Ⅰ,4 with type Ⅱ,1 with type Ⅲ) ; 4 were acrania or hydropic twins; 4 were aeardiac twins,2 were complicated triplet gestation; 1 was twin-twin transfusion syndrome with right ventricular dysplasia and 1 was monochorionic diamniotic (MCDA) with caesarean section history.The procedure was performed under both endoscopic and sonographic guidance.The gestational age at the time of the procedure were 17-27 +6 weeks.The procedure and perinatal outcome were analyzed.Results (1) The procedure was performed successfully in all the 18 cases.The average duration of the procedure was 63 min (24-156 min).The blood loss was 7.6 ml (5-20 ml).The mean gestational age at the time of the procedure was 20 weeks (17-27 +6 weeks).The average birth weight of the neonates was 2441 g(1000-3400 g).(2) There were 20 fetuses survived.Two fetuses had cardiac anomalies and were terminated in the following 2-3 weeks.Intrauterus fetal demise occured in 3 twin reverse arterial perfusion syndrome (TRAP) cases 3-14 weeks after the procedure.1 case delivered as early preterm birth at 28 weeks and the neonate died of respiratory distress syndrome (RDS) and hypoxie-ischemicencephalopathy (HIE).Fourteen neonates were in healthy and normal development by 3-51 months' followup.(3) Fourteen cases delivered at more than 28 weeks (28-38 weeks,averagely 33 + 1 weeks).The gestational weeks were prolonged by 5-21 weeks (averagely 13 +4 weeks).Among them,3 case were early preterm birth (28-33 weeks) and 3 were late preterm birth (34-36 weeks).Conclusion Percutaneous umbilical cord ligation is a reliable technique for the fetocide of complicated monochrionic mutilple gestations,especially for monochronic monoamniotie pregnancies.

Objective To summarize the treatments and perinatal outcomes of patients with twin-twin transfusion syndrome (TTTS).Methods Seventy one cases of TTTS hospitalized in Peking University Third Hospital from January 1,2007 to December 31,2012 were included into the study.They were treated with expectant therapy,amnioreduction,laser surgery or selective fetal reduction.The relationship between outcomes and different staging or treatment procedures of these cases were retrospectively analyzed,and the differences were compared by analysis of variances,Chi-square test and nonparametric test.Results Twenty-five cases received expectant treatment.The rate that at least one baby survived more than 30 days was 32％ (8/25),and 5/15 of the live babies had neonatal brain injury.Sixteen cases received amnioreduction,of which the rate that at least one baby survived more than 30 days was 4/16,and 3/15 of the live babies had brain injury.Twenty-five cases received fetoscopic laser coagulation of vascular anastomoses.The rate that at least one baby survived more than 30 days was 60％ (15/25),which was higher than that of the expectant group and amnioreduction group (x2=4.938,P=0.045 and x2=5.056,P=0.043) ; the brain injury rate among the live babies was 7％ (2/28),which was lower than that of the expectant group (x2=4.702,P=0.040),but similar to the amnioreduction group (x2=1.490,P=0.320).Five patients received selective fetal reduction operation.Among which,one received fetoscopic cord ligation and delivered one healthy baby; the other four cases received radio frequency ablation,after which one was aborted and three delivered at full term.The rate that at least one baby survived more than 30 days was 12/18 in 18 cases with stage Ⅰ TTTS,which was better than that in stage Ⅲ and Ⅳ (4/17 and 6/18) (x2=4.933 and 2.778,both P＜0.05).The rate that at least one baby survived more than 30 days in stage Ⅳ cases was only half of that in stage Ⅰ (6/18 vs 12/18),and the brain injury rate among the live babies was 4/12,similar to that in stage Ⅰ,Ⅱ and Ⅲ [16％ (4/25),0/14 and 2/11,x2=5.361,P=0.118].Conclusion The prognosis of TTTS is very poor,early diagnosis and early treatment could improve the outcomes.Fetoscopic laser coagulation ensures a relatively higher survival rate and low brain injury rate for TTTS.

Objective To evaluate the efficacy of fetoscopic laser occlusion of chorioangiopagous vessels (FLOC) in treatment of twin-twin transfusion syndrome (TTTS) and to investigate the incidence of TTTS complicated with selective intrauterine growth restriction (sIUGR) for better understanding the effects of sIUGR as a complication of TTTS on pregnancy outcomes. Methods A retrospective study was performed on 116 gravidas who were diagnosed with TTTS of Quintero stage Ⅰ - Ⅳ in Peking University Third Hospital from September 2008 to September 2014. Among them, 44 cases received FLOC therapy. The incidences of sIUGR in each Quintero stage of TTTS were analyzed. Pregnancy outcomes of those 44 cases treated with FLOC were observed and the differences among four stage groups were analyzed. Chi-square or Fisher exact test was performed for statistical analysis. Results (1) The survival rates of both twins from stage Ⅰ to Ⅳ groups were 4/7, 10/14, 5/19 and 3/4, respectively, with statistically significant difference (χ2=7.840, P=0.038), but that in stage Ⅲ group was lower than in stage Ⅱ group without significant difference (P'=0.008). Differences in the total fetal survival rate among the four groups were statistically significant [8/14, 75% (21/28), 32% (12/38) and 6/8, χ2=14.016, P=0.002]. The total fetal survival rate in stage Ⅲ group was significantly lower than that in stageⅡ group (P'<0.008). In patients with stage Ⅲ TTTS, those complicated with sIUGR, after receiving FLOC therapy, showed a lower total fetal survival rate than those without sIUGR [21% (6/28) vs 6/10, P<0.05]. (2) Among the 116 TTTS patients, there were 63 cases (54%) with sIUGR complication. Patients with sIUGR complication in TTTS stages Ⅰ to Ⅳ groups accounted for 40% (14/35), 48% (11/23), 78% (28/36) and 46% (10/22), respectively, and the differences were significant (χ2=11.963,P=0.007). The incidence of sIUGR in stage Ⅲ group was greater than that in stage Ⅰ group (χ2=10.482, P'=0.002), and those in both stage Ⅲ and Ⅱ groups were higher than in stage Ⅰgroup without significant difference. Conclusions TTTS patients in stage Ⅲ have lower survival rate of both twins and total fetal survival rates after FLOC therapy, which may be related to a higher incidence of concurrent sIUGR.

Objective:To investigate the effect of placental vascular distribution on residual anastomoses (RA) after fetoscopic laser occlusion of chorioangiopagous ressels (FLOC) for twin to twin transfusion syndrome (TTTS).Methods:A total of 57 cases of TTTS after laser surgery were retrospectively analyzed from April 2014 to April 2019 in Peking University Third Hospital. The patients were divided into RA group (24 cases) and non-RA group (33 cases) according to whether RA occurred in the placenta after laser surgery. The clinical characteristics, perioperative conditions, pregnancy outcomes and placental structure characteristics of the two groups were compared. Multivariate logistic regression was used to analyze the risk factors of placental vascular distribution for RA. The RA group was further divided into non-remission group and remission group, and the placental characteristics and pregnancy outcome of the two groups were compared.Results:(1)General clinical characteristics: the age, application of assisted reproductive technology, incidence of gestational hypertension, gestational diabetes mellitus, preoperative maximum amniotic fluid depth of the donor and recipient twins, Quintero stage and placental position of TTTS patients in the two groups were compared respectively, and there were no statistically significant differences (all P>0.05).The gestational age of patients received FLOC in the RA group was significantly higher than the non-RA group [(23.0±2.4) vs (21.9±2.7) weeks, P=0.033].(2) Perioperative conditions and pregnancy outcomes: the delivery gestational age of the RA group was significantly lower than that of the non-RA group (median:31.8 vs 34.4 weeks, P=0.002);The newborn birth weight in the RA group was significantly lower than that in the non-RA group [(1 648±597) and (2 013±481) g, P=0.003].The birthweight difference in the RA group was significantly higher than that in the non-RA group (median:0.30 vs 0.11, P=0.005). (3) The placental structure and the risk factors influencing RA happened: the differences in the proportion of four types of placental vascular distribution in the RA group and non-RA group were different significantly ( χ2 =10.214, P=0.012), with a detail of parallel type 29% (7/24) and 3% (1/33), staggered type 58% (14/24) and 76% (25/33), hybrid 8% (2/24) and 21% (7/33), monoamniotic membrane type 4% (1/24) and 0 respectively. Multivariate logistic regression analysis showed that parallel placental vascular distribution was an independent risk factor for RA after FLOC ( OR=24.5, 95% CI 1.7-336.2, P=0.017). (4) Placental characteristics and pregnancy outcomes in the remission and non-remission groups of the RA group: the incidence of three kinds of anastomoses, the total number, total diameter and proportion of RA, and the placental territory discordance ratio were compared between the two groups, and there were no statistical significances ( P>0.05);The birth weight difference ratio in the non-remission group was higher than that in the remission group (median:0.41 vs 0.28, P=0.036). Conclusion:The parallel type of placental vascular distribution may be an independent risk factor for RA in TTTS after laser surgery.

Objective:To summarize the pregnancy outcome of monochorionic triamniotic (MCTA) triplet pregnancy and its relationship with multifetal pregnancy reduction.Methods:This study retrospectively recruited 23 women with MCTA pregnancy who delivered at Peking University Third Hospital from January 1, 2012, to January 1, 2020. All 23 cases received regular prenatal examination at our hospital from the first trimester, who were divided into two groups: selective fetal reduction group (randomly reduced one fetus, n=8) and expectant group ( n=15). Pregnancy outcome was described in all participants, differences in maternal age, gestational weeks and outcomes were compared between the two groups. The selective fetal reduction group was further divided into two subgroups: first-trimester vacuum aspiration group ( n=3) and second-trimester radiofrequency ablation group ( n=5), to evaluate the differences in pregnancy outcomes. Two independent samples- t test and Fisher's exact test were used as statistical methods. Results:(1) There was no significant difference in the gestational weeks at the end of the pregnancy [(31.7±4.1) vs (28.8±8.8) weeks], preterm delivery after 32 weeks (9/15 vs 4/8), at least two surviving children (12/15 vs 4/8) and at least one surviving child (13/15 vs 5/8) between the expectant group and the selective fetal reduction group (all P>0.05). One case with twin-twin transfusion syndrome in the expectant group underwent fetoscopic surgery at 19 weeks of gestation and delivered three live infants through cesarean section at 33 +2 weeks due to premature rupture of membranes. One case with twin reversed arterial perfusion sequence at 17 weeks of gestation refused fetal reduction and gave birth to a child at 33 weeks when one fetus's heart stopped beating and one was acardia. (2) The first-trimester vacuum aspiration group and the second-trimester radiofrequency ablation group showed no significant differences in the average gestational weeks at the end of the pregnancy [(28.5±7.6) vs (28.9±10.4) weeks, t=1.145, P>0.05], or the rate of at least one (2/3 vs 3/5, Fisher's exact test, P>0.05) or two surviving children (2/3 vs 2/5, Fisher's exact test, P>0.05). No postoperative infection or amniotic fluid leakage was reported in the subgroups. Conclusions:The pregnancy outcome of MCTA triplet with fetal reduction is not different with expectant group.