Time advantage of HemoCue versus traditional complete blood count during cordocentesis.

OBJECTIVES: During cordocentesis, a significant risk factor for adverse outcome is procedure length. One of the greatest contributors to total procedure length is the time that elapses between obtaining a fetal sample and receiving the results of the complete blood count (CBC) from the hospital laboratory. We aimed to evaluate whether there is an advantage to using a point of care hemoglobinometer (HemoCue) compared with traditional CBC during cordocentesis, measured in time elapsing between obtaining fetal sample, and available result. Secondarily we aimed to compare accuracy of HemoCue in relation to traditional CBC. METHODS: A prospective cohort study was conducted on women undergoing cordocentesis and fetal transfusion for suspected fetal anemia from July 2016 to July 2018 at an urban academic medical center. Fetal blood samples were obtained during cordocentesis, and concurrently sent for traditional CBC, as well as immediately analyzed at bedside using a HemoCue machine. The time elapsing between the obtained fetal sample and availability of results with HemoCue versus traditional CBC were recorded. Primary outcome was time elapsed between obtaining fetal sample and result available for HemoCue versus traditional CBC. Secondary outcome was comparison of HemoCue and CBC hemoglobin values for accuracy. RESULTS: Forty-five fetal samples were compared using CBC and HemoCue. Sixteen cordocentesis procedures were performed on 10 patients during the study period. Use of HemoCue was associated with a significantly shorter time to yield a fetal hemoglobin result, compared to traditional CBC (1.5 versus 5.5 min, p = .0001). Results yielded by the HemoCue highly correlated to those yielded by traditional CBC (R = 0.96). CONCLUSIONS: Use of HemoCue during cordocentesis is associated with a 4-min time advantage over traditional CBC. Hemoglobin results yielded by HemoCue and traditional CBC are highly correlated.KEY MESSAGEUse of a point-of-care hemoglobinometer is associated with a time advantage of 4 min over traditional complete blood count during cordocentesis. This represents a potentially modifiable risk factor for procedure length, and thus procedure complications.

Cordocentesis-associated fetal loss and risk factors: single-center experience with 6650 cases.

OBJECTIVES: To identify procedural risk factors associated with fetal loss following cordocentesis and to determine the rate of cordocentesis-related fetal loss associated with the current cordocentesis protocol used in our institution. METHODS: This was a retrospective cohort study of pregnancies that underwent midpregnancy cordocentesis in a single center (a tertiary hospital, teaching school), between 1992 and 2018, based on data retrieved from our prospective database. All consecutive cases were validated to retrieve those meeting the eligibility criteria, which included: singleton pregnancy without underlying maternal disease, normal fetus (no structural or chromosomal abnormality or severe disorder), gestational age between 16 and 24 weeks at the time of the procedure and availability of pregnancy outcome. Cases that resulted in termination of pregnancy were excluded. We assessed the effect of prior cordocentesis model training on the fetal-loss rate and procedure-related complications, and evaluated potential risk factors of fetal loss secondary to cordocentesis, including procedure difficulty, placenta penetration, prolonged bleeding, fetal bradycardia, puncture site and early gestational age at procedure. Pregnancy outcomes were compared between the study group and a control group of women, who did not undergo cordocentesis, selected randomly at a 1:1 ratio from our obstetric database. RESULTS: A total of 10 343 procedures were performed during the study period, of which 6650 met the eligibility criteria and were included in the analysis. The fetal-loss rate in the first 60 procedures (early practice) of six operators (n = 360 procedures), who did not have prior model training, was significantly higher than that during the early practice of 18 operators (n = 1080 procedures) with prior model training (6.9% vs 1.6%; P < 0.001); whereas the fetal-loss rate in the next 60 procedures of practice was comparable between the two groups. After excluding the first 360 procedures of the groups without prior model training, the overall fetal-loss rate in pregnancies that underwent cordocentesis was significantly higher than that in the control group (1.6% vs 1.0%; P < 0.001). Considering the fetal-loss rate in the normal controls as background loss, the incremental cordocentesis-associated fetal-loss rate was 0.6%. Penetration of the placenta (odds ratio (OR), 2.65 (95% CI, 1.71-4.10)), prolonged bleeding from the puncture site (OR, 10.85 (95% CI, 5.27-22.36)) and presence of fetal bradycardia (OR, 3.32 (95% CI, 1.83-6.04)) during cordocentesis were independent risk factors associated with fetal loss. CONCLUSIONS: Cordocentesis model training markedly reduces fetal loss during the early learning curve of practice. Thus, cordocentesis practice without prior model training should not be acceptable. Significant procedural risk factors for fetal loss secondary to cordocentesis are placental penetration, prolonged bleeding and fetal bradycardia. Cordocentesis-related fetal loss may be only 0.6%, much lower than the rate reported previously. Copyright © 2020 ISUOG. Published by John Wiley & Sons Ltd.

Effect of cordocentesis on fetal myocardial performance.

OBJECTIVE: To compare fetal Tei index before, immediately after and 30 min after cordocentesis for prenatal diagnosis. PATIENTS AND METHODS: Pregnant women undergoing prenatal diagnostic cordocentesis in the early mid-trimester underwent measurement of the fetal Tei index of both right and left ventricles just before cordocentesis, immediately after and at 30 min after the procedure. RESULTS: A total of 143 singleton women underwent cordocentesis at a median gestational age of 19 weeks (range 16-23). The most common indication was fetal risk of beta-thalassemia/hemoglobin E disease (42%, 60 cases). Immediately after cordocentesis, fetal Tei index and all its components at both ventricles were significantly altered when compared with the baseline values (p < 0.001). At 30 min after cordocentesis, components of the Tei index had significantly improved but 5/6 had not completely recovered. No serious procedure-related short-term complications were observed in the study. CONCLUSION: Cordocentesis has a negative impact on fetal hemodynamics as indicated by worsening of the Tei index. Although the adverse effect seems to be temporary, the recovery time may be longer than 30 min. © 2016 John Wiley & Sons, Ltd.

Omission of fetal sampling in treatment of subsequent pregnancies in fetal-neonatal alloimmune thrombocytopenia.

BACKGROUND: Fetal-neonatal alloimmune thrombocytopenia affects approximately 1 of 1000 live births, most of which are not severely thrombocytopenic. Despite effective treatment with intravenous gammaglobulin and/or prednisone, antenatal management of a subsequent affected pregnancy is complicated by the risks associated with fetal blood sampling. Furthermore, there are no biomarker(s) of high risk other than the occurrence of intracranial hemorrhage in a previous sibling. Management of these high-risk pregnancies requires intensive treatment initiated at 12 weeks of gestation. OBJECTIVE: The objective of the study was to evaluate whether empiric escalation of therapy at 32 weeks allows the omission of fetal blood sampling in all fetal-neonatal alloimmune thrombocytopenia-affected patients. Specifically, we sought to determine whether intensive intravenous gammaglobulin-based regimens for the treatment of a subsequent fetal-neonatal alloimmune thrombocytopenia-affected pregnancy followed by empirically escalated intravenous gammaglobulin and prednisone treatment would increase the fetal platelet count and thus safely allow omission of fetal blood sampling in the antepartum management of these patients. STUDY DESIGN: In this prospective, multicenter, randomized controlled study, 99 women with fetal-neonatal alloimmune thrombocytopenia whose prior affected child did not have an intracranial hemorrhage were randomized to receive an intensive intravenous gammaglobulin-based regimen: 2 g/kg per week or intravenous gammaglobulin 1 g/kg per week plus prednisone 0.5 mg/kg per day, starting at 20-30 weeks of gestation. Escalated therapy (intravenous gammaglobulin 2 g/kg per week plus prednisone 0.5 mg/kg per day) was recommended and usually initiated at 32 weeks when fetal counts were <50,000/mL(3) or when fetal blood sampling was not performed. The preliminary report of this study from 2007 demonstrated the efficacy of both intravenous gammaglobulin-based regimens in most patients. Most patients who underwent fetal sampling had adequate fetal counts and therefore did not have their treatment escalated. This post hoc analysis describes the 29 fetuses who had their treatment escalated either because they had low counts at 32 weeks or when sampling was not performed. This study explored whether the empiric escalation of treatment at 32 weeks was sufficiently effective in increasing fetal platelet counts in these patients. RESULTS: Mean fetal and birth counts of fetuses randomized to each of the 2 initial treatment groups were all >100,000/mL(3). Three neonates had an intracranial hemorrhage; all 3 were grade 1 and all had birth platelet counts >130,000/mL(3). In a post hoc analysis, 19 fetuses undergoing fetal blood sampling at 32 weeks had fetal platelet counts <50,000/mL(3) despite their initial treatment. Of these 19, birth platelet counts were >50,000/mL(3) in 11 of 13 fetuses who received escalated treatment compared with only 1 of 6 of those who did not (P = .01); only 3 fetuses that received initial therapy followed by escalated treatment had birth platelet counts <50,000/mL(3) and none had an intracranial hemorrhage. The platelet counts of 14 of 15 fetuses that received empirically escalated treatment without sampling were >50,000/mL(3) at birth. In addition, none of these had an intracranial hemorrhage. CONCLUSION: The 2 recommended protocols of intensive initial treatment followed by empiric escalation of therapy at 32 weeks of gestation are reasonably safe, effective in increasing fetal platelet counts, and allow omission of fetal blood sampling by increasing the fetal platelet count in almost all cases.

Percutaneous umbilical blood sampling: current trends and outcomes.

OBJECTIVES: To report our contemporary experience with PUBS, including indications and complications, stratified by the presence of hydrops fetalis. STUDY DESIGN: All PUBS performed from 1988 to 2013 at a single tertiary care center were identified using a comprehensive ultrasound database. We recorded patient demographics, relevant obstetric, fetal and neonatal data, indication for and success of PUBS and any complications. Data were analyzed using SAS, version 9.3 (SAS Institute Inc., Cary, NC). RESULTS: 455 PUBS were performed on 208 pregnant women, 97.8% of which were successful. The average gestational age at the time of PUBS was 26.7 weeks (SD 5.1 weeks, range 17.5-41.3 weeks). Indications were available for 441: 245 (55.6%) isoimmunization, 77 (17.5%) non-immune hydrops fetalis (NIHF), 98 (22.2%) chromosomal diagnosis, and 21 (4.8%) other indications. Isoimmunization was a less common indication for PUBS in 2008-2013 as compared to 1988-1992 (51.7% vs 66.2%, p=0.07). Amongst PUBS performed in the setting of hydrops, isoimmunization was much less common in the later time period (61.1% vs 0%, respectively; p<0.01). The procedure complication rate (bradycardia or fetal demise at procedure) of 2.5% was stable over the study period and was most common with NIHF (2.0% without hydrops, 0% with immune hydrops and 6.3% with NIHF; p=0.04). Of the 208 women with a PUBS performed, 74 had more than one PUBS procedure (mean 2.2, max 18). Transfusions were performed in 233 of the 455 (51.2%). Overall, 10.2% of the pregnancies had an intrauterine fetal demise (IUFD) within 2 weeks of the procedure, which was most common in pregnancies with NIHF (3.2% without hydrops, 9.1% with immune hydrops and 31.7% with NIHF; p<0.01). The IUFD rate was 60% (3/5) in fetuses with parvovirus-mediated NIHF. CONCLUSIONS: PUBS has a high likelihood of success with a relatively low complication rate. The complication rate is highest in pregnancies with NIHF, and these pregnancies are also at a significantly higher risk of IUFD, particularly those patients with parvovirus-mediated NIHF. Our findings can be used when counseling patients who are considering PUBS for diagnostic or therapeutic purposes.

Interventions et techniques de diagnostic prénatal visant l'obtention d'un prélèvement fœtal à des fins diagnostiques : Risques et avantages pour la mère et le fœtus.

OBJECTIF: Offrir aux fournisseurs de soins de maternité et à leurs patientes des lignes directrices factuelles contemporaines en ce qui concerne les services de counseling traitant des risques et des avantages maternels propres à la tenue des interventions diagnostiques prénatales orientées par échographie (et/ou des techniques permettant l'établissement d'un diagnostic génétique) nécessaires dans les cas où il a été établi pendant la période prénatale que la grossesse serait exposée à des risques, ainsi qu'en ce qui concerne la prise de décisions subséquentes quant à la prise en charge de la grossesse (questions abordant des aspects tels que le niveau du fournisseur de soins obstétricaux, la surveillance prénatale, le lieu où devraient se dérouler les soins et l'accouchement, et la décision de poursuivre ou d'interrompre la grossesse). La présente directive clinique se limite aux services de counseling traitant des risques et des avantages maternels, et aux décisions en matière de prise en charge de la grossesse pour les femmes qui nécessitent (ou qui envisagent) la mise en œuvre d'une intervention ou d'une technique effractive orientée par échographie aux fins de l'établissement d'un diagnostic prénatal. POPULATION DE PATIENTES: Femmes enceintes identifiées, à la suite de la mise en œuvre de protocoles établis de dépistage prénatal (taux sériques maternels ± imagerie, résultats d'analyse de l'ADN acellulaire indiquant des risques élevés, résultats anormaux au moment de l'imagerie fœtale diagnostique ou antécédents familiaux de troubles héréditaires), comme étant exposées à un risque accru d'anomalie génétique fœtale. Ces femmes pourraient nécessiter ou demander des services de counseling au sujet des risques et des avantages pour la grossesse de la tenue d'une intervention effractive orientée par échographie visant à déterminer l'étiologie, le diagnostic, et/ou la pathologie de possibles anomalies fœtales. RéSULTATS: La littérature publiée a été récupérée par l'intermédiaire de recherches menées dans Medline, PubMed et The Cochrane Library jusqu'en juin 2014 au moyen d'un vocabulaire contrôlé (« prenatal diagnosis ¼, « amniocentesis ¼, « chorionic villi sampling ¼, « cordocentesis ¼) et de mots clés (« prenatal screening ¼, « prenatal genetic counselling ¼, « post-procedural pregnancy loss rate ¼) appropriés. Les résultats ont été restreints aux analyses systématiques, aux études observationnelles et aux essais comparatifs randomisés / essais cliniques comparatifs publiés en anglais entre janvier 1985 et juin 2014. Les recherches ont été mises à jour de façon régulière et intégrées à la directive clinique jusqu'en juin 2014. La littérature grise (non publiée) a été identifiée par l'intermédiaire de recherches menées dans les sites Web d'organismes s'intéressant à l'évaluation des technologies dans le domaine de la santé et d'organismes connexes, dans des collections de directives cliniques, dans des registres d'essais cliniques et auprès de sociétés de spécialité médicale nationales et internationales. VALEURS: La qualité des résultats a été évaluée au moyen des critères décrits dans le rapport du Groupe d'étude canadien sur les soins de santé préventifs (Tableau 1). AVANTAGES, DéSAVANTAGES ET COûTS: Consentement éclairé de la patiente, transfert des connaissances, évaluation du risque génétique prénatal, soulagement de l'anxiété, création d'anxiété, défense des droits, compréhension du dépistage fœtal, limites du dépistage fœtal, choix en matière de prise en charge de la grossesse, complication de la grossesse ou fausse couche, soins opportuns et améliorés pour l'accouchement d'un enfant présentant une morbidité reconnue. RECOMMANDATIONS.

Effects of in utero cord blood collection on post-cesarean hemoglobin levels.

OBJECTIVE: To assess effects of in utero cord blood collection on postoperative hemoglobin, hematocrit levels. STUDY DESIGN: Elective cesarean deliveries in which cord blood was collected were compared with match paired elective cesarean deliveries without cord blood collection. Pre-post-operative hemoglobin and hematocrit level differences were compared between study groups with Student's t test. Multivariate regression models were used to address confounders. Correlation between volume of collected UCB and mean decrease in blood count parameters was analyzed. RESULTS: A total of 399 cesarean deliveries during a 12 months period were included in the analysis. Mean decrease in hemoglobin levels was 1.08g/dL (SD=1.0) in UCB collected group compared to 0.84g/dL (SD=1.0) in control group (p=0.002). Mean decrease in hematocrit levels was 3.1% (SD=3.4) in cord blood collected cesarean delivery group compared to 1.9% (SD=2.4) in control group (p=0.002). Univariate analysis has shown the collected UCB volume to be uncorrelated with the change in hemoglobin levels (r=0.013). Multivariate regression models, after adjusting for birth weight, age and number of prior cesarean, have shown the UCB collection to be significantly associated with the mean decrease in blood count parameters (estimate=0.23g/dL, t=-2.23, p=0.02). CONCLUSION: In utero UCB collection is associated with a small increase in bleeding of little clinical importance. Amount of UCB is not associated with amount of change in hemoglobin and hematocrit levels. In utero UCB collection seems to be safe for expectant mothers scheduled for low-risk cesarean delivery.

Second-trimester cordocentesis and the risk of small for gestational age and preterm birth.

OBJECTIVE: To estimate the association of cordocentesis with small for gestational age, preterm birth, and low birth weight. METHODS: A cohort study from a tertiary care center. Pregnant women without medical or obstetric complications and without ultrasonographically evident fetal anomalies scheduled for cordocentesis between 16 and 22 weeks of gestation (predominantly to detect severe fetal hemoglobinopathies) were prospectively enrolled and matched to a similarly healthy control group on a one-to-one basis by maternal age, parity, gestational age. and ethnicity. In the cordocentesis group, pregnancies found to be complicated by a fetal hemoglobinopathy or a karyotypic abnormality were excluded. Both groups were followed until delivery. The primary outcomes included the rates of small-for-gestational-age preterm birth and low birth weight and fetal loss. RESULTS: In total, 7,228 women underwent cordocentesis, of whom 5,506 qualified as cases. Of these, 5,039 were matched to women in the control group and had complete outcome data available for the pair. The rates and relative risks (RRs) of small for gestational age (6.9% compared with 4.6%; RR 1.5, 95% confidence interval [CI] 1.3-1.8), preterm birth (12.7 compared with 7.4%; RR 1.7, 95% CI 1.5-1.9), and fetal loss (1.9% compared with 1.0%; RR 1.9, 95% CI 1.4-2.7) were significantly higher among fetuses in the cordocentesis group. However, there were no significant differences in other obstetric complications between the study and control groups. CONCLUSION: Rates of small for gestational age, preterm birth, low-birth weight, and fetal loss are increased among pregnancies with cordocentesis in the second trimester.

Fetal blood sampling.

OBJECTIVE: We sought to review indications, technical aspects, risks, and recommendations for fetal blood sampling (FBS). METHODS: A systematic review was performed using MEDLINE, PubMed, EMBASE, and Cochrane Library using the terms "fetal blood sampling," "percutaneous umbilical blood sampling," and "cordocentesis." The search was restricted to English-language articles published from 1966 through July 2012. Priority was given to articles reporting original research, in particular randomized controlled trials, although review articles and commentaries also were consulted. Abstracts of research presented at symposia and scientific conferences were not considered adequate for inclusion in this document. Evidence reports and guidelines published by organizations or institutions such as the National Institutes of Health, Agency for Health Research and Quality, American Congress of Obstetricians and Gynecologists, and Society for Maternal-Fetal Medicine were also reviewed, and additional studies were located by reviewing bibliographies of identified articles. Grade (Grading of Recommendations Assessment, Development, and Evaluation) methodology was employed for defining strength of recommendations and rating quality of evidence. Consistent with US Preventive Task Force guidelines, references were evaluated for quality based on the highest level of evidence. RESULTS AND RECOMMENDATIONS: Ultrasound-guided FBS is the only procedure that provides direct access to the fetal circulation. When invasive testing is planned for suspected severe fetal anemia or thrombocytopenia, we recommend FBS as the procedure of choice, with availability of immediate transfusion if confirmed. We recommend against the use of FBS for indications in which other less invasive, and therefore lower risk, alternatives are available. The overall success rate of FBS is high, and blood samples can be obtained in >98% of patients. We suggest that counseling for FBS include discussion about the potential risk of FBS that may include, but may not be limited to: bleeding from puncture site (20-30%); fetal bradycardia (5-10%); pregnancy loss (≥1.3%, depending on indication, gestational age, and placental penetration); and vertical transmission of hepatitis or human immunodeficiency virus. We recommend that FBS be performed by experienced operators at centers with expertise in invasive fetal procedures when feasible.

Evaluation of passage of fetal erythrocytes into maternal circulation after invasive obstetric procedures.

AIM: The aim of this study was to evaluate the passage of fetal erythrocytes into the maternal circulation after invasive obstetric procedures, using the Kleihauer-Betke test, flow cytometry and α-fetoprotein concentration in maternal blood. MATERIAL AND METHODS: This was a prospective descriptive study on patients who underwent: amniocentesis, cordocentesis, chorionic villus sample, amniotic infusion, bladder drainage and ventricular-amniotic shunt to investigate the karyotype; treatment for hydrocephalus, oligohydramnios, obstructive uropathy and polyhydramnios; and investigation of lung maturity. Maternal blood samples were collected before and 60 min after the invasive obstetric procedure in order to evaluate the passage of fetal erythrocytes using the Kleihauer-Betke test, flow cytometry and α-fetoprotein concentration. RESULTS: In total, 43 invasive obstetric procedures were performed. The procedures performed were: 27 cases of amniocentesis (62.7%), seven cases of cordocentesis (16.2%), four chorionic villus samples (9.4%), two amniotic infusions (4.7%), two ventricular-amniotic shunts and one bladder drainage (2.3%). After one case of cordocentesis with two puncture attempts via the placenta, a significant increase in fetal erythrocytes was detected using the three methods. After another cordocentesis with one puncture via the placenta, a significant increase in fetal erythrocytes was detected using flow cytometry and α-fetoprotein concentration, but not through the Kleihauer-Betke test. The other 41 samples did not show any significant increase in fetal erythrocytes in the maternal blood. CONCLUSION: Invasive obstetric procedures performed during prenatal care are safe when performed by experienced professionals with the proper technique, with minimal chance of passage of fetal erythrocytes into the maternal compartment.

[Application and evaluation of invasive prenatal diagnostic techniques and analysis of chromosomal karyotype].

OBJECTIVE: To evaluate the safety, effectiveness and complications of serial invasive prenatal diagnostic techniques, and to investigate the prenatal diagnosis indication as well as to analyze the abnormal chromosomal karyotype. METHODS: We retrospectively studied all patients from March 2005 to May 2012 who received amniocentesis and cordocentesis in the prenatal diagnosis center of Second Xiangya Hospital. The indication of the procedure, successful rate and complications were evaluated, and 25 abnormal chromosome nuclear types were analyzed. RESULTS: A total of 669 patients received invasive prenatal diagnosis from March 2005 to May 2012 in Second Xiangya Hospital: 598 received amniocentesis and 71 cordocentesis carried out. Compared with the cordocentesis group, the amniocentesis group had higher achievement ratio (91.54% vs 100%, P<0.05), lower spontaneous abortion rate (1.41% vs 0.33%, P<0.05), fewer abnormal karyotypes (11.27% vs 2.84%, P<0.05) and lower expenditure (880 yuan vs 800 yuan, P<0.05). Positive screening, advanced maternal age, and ultrasonography abnormality were the top 3 indications of amniocentesis and cordocentesis. We found 25 abnormal karyotypes, including 6 cases of trisomy 21, 4 sex chromosomal abnormalities, 7 autosomal balanced translocations, 1 marker chromosome, and 7 mosaics. CONCLUSION: As a widely used invasive prenatal diagnosis, amniocentesis is safe and effective. The complications of cordocentesis are much higher than those of amniocentesis, which is not a proper routine procedure for prenatal diagnosis of abnormal karyotype. The analysis of karyotype not only can identify fetal chromosome abnormality, but also provide the scientific basis for pregnancy continuation, thus reducing the ratio of birth defect.

[Predictive factors for fetal tolerance to cordocentesis: a monocentric retrospective study]. / Facteurs prédictifs de tolérance fœtale à la cordocentèse : étude rétrospective monocentrique.

OBJECTIVES: Indications for fetal blood sampling (FBS) are getting more limited. In this context, we aimed to evaluate fetal loss and morbidity associated with FBS and to precise the predictive parameters for fetal complications. More than a retrospective evaluation of our practices, the final end point of our study was to better inform the patients coming to our centre. PATIENTS AND METHODS: Retrospective monocentric cohort (Canadian Task Force classification II-2) of the 99 FBS performed between April 2004 and June 2010 on 80 fetuses, after excluding the procedures done for termination of pregnancy. The main clinical outcome was a composite outcome criteria for fetal tolerance including cesarean section for abnormal non stress test within the 24 hours, or any event responsible of a modified obstetrical management during the 14 day following FBS. RESULTS: Mean maternal age at FBS was 30 years ± 5.13 SD and parity was 2.49 ± 1.38 SD. FBS was performed by an experienced operator in 86.5% of cases (CI 95%, 78-92.6); with a single insertion in 83.3% of circumstances (CI 95%, 74.4-90.2). The mean duration was 11 min ± 6.37 SD. The total rate of intrauterine death, in our series, was 7.1% (CI 95%, 2.9-14), including all reported fetal demise within the 14 days after FBS, whatever the relation with the procedure. Our study demonstrated a 9.1% occurrence of post-FBS altered CTG fetal testing (CI 95%, 4.2-16.6), half of it with spontaneous resolution. The rate of severe complications (main clinical outcome) was 11.1% (CI 95%, 5.7-19) including one fetal death liable to FBS and 10 emergency caesarean sections: 5.1% for fetal bradycardia (CI 95%, 1.7-11.4), 2% for placental abruption (CI 95%, 0.2-7.1), 2% for premature preterm rupture of membranes (CI 95%, 0.2-7.1) and 1% for significative umbilical cord bleeding (CI 95%, 0-5.5). Univariate factor analysis highlights 4 parameters for impaired fetal tolerance; a prolonged procedure, presence of low fetal platelets (<30.10(9)/L); and FBS performed for fetal anaemia during Parvovirus B19 infection or allo-immune thrombocytopenia. DISCUSSION AND CONCLUSION: FBS remains a tricky procedure with a substantial risk of fetal loss or complications especially when performed on high-risk fœtuses. The length of the procedure should be shortened as much as possible (trained operator, postponed procedure when all favourable condition are not available). Fetal thrombocytopenia is a meaningful risk factor encouraging carefulness when exploring allo-immune fetal thrombocytopenia.

Effect of umbilical cord bleeding following mid-pregnancy cordocentesis on pregnancy outcomes.

OBJECTIVES: To compare the adverse pregnancy outcomes among the three groups of umbilical cord bleeding following cordocentesis; a group of no bleeding (group 1), transient bleeding (group 2), and persistent bleeding (>60 s: group 3). METHODS: Consecutive cases of cordocentesis were prospectively recorded and followed up. The inclusion criteria for analysis consisted of (1) singleton pregnancies; (2) gestational age of 18-22 weeks; (3) no fetal anomalies; (4) no previous invasive procedures; (5) performed by experienced operators, and (6) known pregnancy outcomes. The main outcomes were rates of fetal loss, low birth weight and preterm birth. RESULTS: Of 2,174 procedures, 1,614 were in group 1, 509 were in group 2, and 51 were in group 3. The mean birth weight and gestational age at delivery were significantly lower in group 3 than those in groups 1 and 2. The fetal loss rate was significantly higher in group 3. Rates of low birth weight and preterm birth were significantly higher in group 3 whereas the rates in group 2 had a tendency to be higher than those in group 1. CONCLUSION: This study suggests that cord bleeding during cordocentesis carries a higher risk of fetal loss, low birth weight and preterm birth.

A comparison of cordocentesis outcomes between early and conventional procedures.

OBJECTIVE: To compare procedural outcomes between early cordocentesis (16-17 weeks) and those at 18-22 weeks. MATERIALS AND METHODS: A prospective database of cordocentesis was assessed. The eligible criteria included are (1) singleton pregnancy; (2) no fetal abnormalities; (3) gestational age of 16-22 weeks and (4) procedures performed by experienced operators. The procedures performed during 16-17 weeks were defined as early cordocentesis (Study group). The Control group (conventional cordocentesis; 18-22 weeks) were selected by matching maternal age and years of procedures, with a ratio of 1:3. RESULTS: Of 2942 eligible procedures, 103 procedures were undertaken during 16-17 weeks and 309 matched controls were selected. Baseline characteristics of both groups were comparable. Time used to complete the procedure was significantly longer in Study group (8.45 ± 9.91 vs. 6.07 ± 6.63 min; p value 0.007). Similarly, rate of difficult procedures was significantly higher in Study group (7.8 vs. 2.3%; p value 0.011). However, rates of fetal loss, low birth weight infants and preterm births were not significantly different, but there was a tendency to be higher in Study group. CONCLUSION: Early cordocentesis is more difficult but relatively safe when performed by experienced hands, although it has a tendency to increase rates of adverse outcomes. This information may be helpful in counseling the couples.

Predisposing factors and effects of fetal bradycardia following cordocentesis at mid-pregnancy.

OBJECTIVES: To identify predisposing factors of fetal bradycardia following cordocentesis at mid-pregnancy and to compare the pregnancy outcomes to those without bradycardia. METHODS: All cordocenteses performed at 18-22 weeks of gestation were prospectively enrolled. The inclusion criteria consisted of: (i) singleton pregnancies; (ii) no fetal structural or chromosomal abnormalities; (iii) the procedures done by experienced operators. They were divided into two groups; procedures with fetal bradycardia (Group 1) and those without bradycardia (Group 2). Factors related to bradycardia were identified and pregnancy outcomes between the two groups were also compared. RESULTS: Of 6147 cordocenteses recruited, 2829 met the inclusion criteria. Of these,152 had fetal bradycardia whereas the remaining 2677 did not. The procedures involving placenta penetration, and umbilical cord bleeding were significantly related to a higher rate of fetal bradycardia. On the other hand, cordocenteses with fetal bradycardia had a significantly higher rate of fetal loss (11.8 vs. 1.9%, respectively, p = 0.001) as well as a higher rate of low birth weight and preterm birth. CONCLUSIONS: Cordocentesis with placenta penetration and umbilical cord bleeding carries a higher risk for fetal bradycardia and fetal bradycardia was an independent factor for a higher rate of fetal loss, preterm birth and low birth weight.

Early procedure-related complications of fetal blood sampling and intrauterine transfusion for fetal anemia.

OBJECTIVE: To review the procedure-related complication rates following fetal blood sampling and intrauterine red cell transfusion for anaemic fetuses at a single tertiary center. DESIGN: A retrospective study of 114 intrauterine transfusions. SETTING: A single tertiary referral fetal medicine center at Queen Charlotte's and Chelsea Hospital, Imperial College London, London, UK. SAMPLE: All cases (114) undergoing fetal blood sampling and intrauterine transfusion between January 2003 and May 2010. METHODS: Early procedure-related complications (severe fetal bradycardia requiring either abandonment of the procedure or emergency delivery, fetal death, preterm labor or rupture of membranes) were investigated by review of computerized records and individual chart review. MAIN OUTCOME MEASURES: Live birth rate, perinatal mortality, procedure-related fetal bradycardia, preterm labor and procedure-related spontaneous rupture of membranes. RESULTS: The majority of cases (77.8%) were due to red cell alloimmunization, with anti-D being the commonest cause. The live birth rate was 93.5%, with a procedure-related fetal death rate of 0.9%. The preterm labor rate (<37 weeks' gestation) was 3.5% only occurring in patients undergoing multiple (>3) fetal transfusions. Complications in this series did not appear to be increased the earlier the gestation at which the first transfusion took place. CONCLUSIONS: Despite a reduction in the number of cases requiring intrauterine therapy for fetal anemia, contemporary outcomes appear to be good if not improving. It is important that the experience required to manage these cases should be concentrated in fewer centers to maximize good perinatal outcome.

Effect of placenta penetration during cordocentesis at mid-pregnancy on fetal outcomes.

OBJECTIVES: To compare the rates of fetal loss, low birth weight, and preterm birth between pregnancies undergoing cordocentesis at mid-pregnancy with placenta penetration and those without it. METHODS: Consecutive cases of cordocenteses were prospectively recorded. The inclusion criteria for analysis were: (1) singleton pregnancies, (2) no fetal abnormalities, (3) gestational age of 18-22 weeks, and (4) procedures performed by experienced operators. The primary outcome was fetal loss rate, and the secondary outcomes were rates of failed procedures, low birth weight, and preterm birth. RESULTS: Of 6147 cordocenteses recorded, 2829 met the inclusion criteria with complete data for analysis. Of these, 654 procedures were further excluded because the puncture site was at cord insertion. The remaining 2175 cases, consisting of 615 procedures with placenta penetration and 1560 cases with no penetration, were analyzed. Cordocenteses with placenta penetration had a significantly higher rate of fetal loss (3.6% vs 1.3%, p = 0.01) as well as of low birth weight and preterm birth. CONCLUSION: Cordocentesis with placenta penetration carries a higher risk for fetal loss, preterm birth, and low birth weight. This information may be helpful in prenatal diagnosis counseling, and it may encourage performers to avoid placenta penetration, if possible.

Comparisons of outcomes after cordocentesis at mid-pregnancy between singleton and twin pregnancies.

OBJECTIVE: To compare the outcomes after mid-pregnancy cordocentesis between singleton and twin pregnancies. METHODS: We compared immediate complications and pregnancy outcomes between a cohort of twin pregnancies undergoing mid-pregnancy diagnostic cordocentesis between the years 1989 and 2010, and a control group of singleton pregnancies matched based on maternal age and years of the procedure with a ratio of 1:3. RESULTS: Among 6147 pregnancies undergoing cordocentesis during the study period, 122 twin fetuses met the study criteria and were matched with 336 singleton controls. Success rate of sampling was slightly higher in singleton than in twin gestations (98.8% vs 97.3%), and time required for the procedure was significantly longer in the twin group (8.1 vs 6.3 min, p = 0.02). Immediate complications, such as fetal bradycardia and transient bleeding from the puncture site, were significantly higher in twins (13% vs 6.0%, p = 0.001; and 34.8% vs 26.1%, p = 0.03, respectively). However, fetal loss rate within 2 weeks of cordocentesis was not different (1.4% and 1.1%, p = 0.42). CONCLUSION: Immediate complications following cordocentesis are significantly higher in twin pregnancies, but fetal loss rate within 2 weeks of the procedure is comparable.

Effect of cord puncture site in cordocentesis at mid-pregnancy on pregnancy outcomes.

OBJECTIVES: To compare the procedure and pregnancy outcomes of pregnancies undergoing cordocentesis between a group of cord insertion puncture and that of free loop puncture. MATERIALS AND METHODS: Pregnancies undergoing cordocenteses meeting the following inclusion criteria were recruited: (1) singleton pregnancies at gestational ages of 18-22 weeks; (2) no fetal abnormalities; (3) the procedures performed by experienced operators; and (4) the procedures of no placenta penetration. The recruited cases were classified into two groups: a group of cordocenteses with puncture site at placental cord insertion (Group 1) and those with puncture site at cord free loop (Group 2). The primary outcomes to be compared were rates of fetal loss, newborns with low birth weight and preterm birth. The secondary outcomes included a rate of successful procedures, umbilical cord bleeding, fetal bradycardia, maternal blood contamination, and duration of the procedure time. RESULTS: Of 6147 cordocenteses recruited, 2214 met inclusion criteria. The mean duration to complete the procedure in Group 1 was significantly shorter than that in Group 2 (4.5 ± 5.4 vs. 6.7 ± 8.5 min, Student's t-test; p = 0.001). The mean birth weight and gestational age at delivery were comparable between the two groups. No significant differences between the two groups were seen in rates of fetal loss, low birth weight, preterm birth, successful procedures, umbilical cord bleeding, or fetal bradycardia. However, the rate of maternal blood contamination was significantly higher in the group of puncture at the cord insertion site. CONCLUSION: Of cordocenteses performed based on accessibility and quality of visualization, cord insertion puncture may cause more maternal blood contamination but free loop puncture may be associated with more difficult procedures, while the safety was comparable.

Fetomaternal transfusion after amniocentesis and cordocentesis.

OBJECTIVE: To compare the extent of fetomaternal transfusion after amniocentesis and cordocentesis. SETTING: Three-hundred and forty-five amniocentesis and 268 cordocentesis were performed for genetic indications. The extent of fetomaternal transfusion was calculated on the basis of the maternal serum alpha-fetoprotein level changes. RESULTS: The mean fetomaternal transfusion was 6.3 and 62 µL in the amniocentesis and cordocentesis groups, respectively. Transplacental needle passage and longer procedural time were risk factors for fetomaternal transfusion. The frequency of transplacental passage was higher and the procedural time was longer in the cordocentesis group. The fetal loss rate was 1.17% after amniocentesis and 1.2% after cordocentesis, respectively. CONCLUSIONS: Cordocentesis causes more injury to the extrafetal compartment, which results in a higher level of fetomaternal transfusion. However, though a nearly ten times higher fetomaternal transfusion was observed after cordocentesis, there was no essential difference in pregnancy outcome between the two groups.