Blood contamination of amniotic fluid after amniocentesis in relation to placental location

Amniocentesis-When It Is Clear That It Is Not Clear

A fetus identified to be at risk for chromosomal abnormalities may benefit from identification of genetic defects through amniocentesis. Although the risks associated with amniocentesis are considered to be minimal, being an invasive procedure it is not completely without complications.

BACKGROUND AND OBJECTIVES

The current study aims to identify correlations between blood contamination of samples collected during amniocentesis and certain factors dependent on the instruments used (thickness of the needle used to aspirate the fluid), the location of the placenta, and uterine vascularity (more pronounced in multiparous patients).

MATERIALS AND METHODS

The study included 190 patients in the second trimester of pregnancy who met one of the criteria for invasive prenatal diagnosis (age over 35 years, high risk in first trimester screening, history of pregnancies with genetic abnormalities, etc.). The amniotic fluid samples collected from these patients were analyzed in terms of blood contamination of the amniotic fluid aspirated with maternal cells Results: Of the patients in whom the procedure was performed using 21 G size needles, 16 samples (13.33% of the total) were contaminated. None of the samples collected from patients where a 20 G needle was used were contaminated. There was a statistically significant association between the lack of contamination and the use of Doppler ultrasound in multiparous patients with anterior placenta in whom a 21-gauge needle was used for amniocentesis.

CONCLUSIONS

There is an increased rate of sample contamination (statistically significant) when using 21 G needle sizes and a significant difference in contamination between primiparous and multiparous patients, with contamination being more frequent in multiparous patients. The use of Doppler ultrasonography may benefit the procedure, as the contamination rate was significantly reduced when used during amniocentesis.

Guideline No. 409: Intrauterine Fetal Diagnostic Testing in Women with Chronic Viral Infections

OBJECTIVE

This revised guideline provides updated information for the care of women with chronic viral infections who require intrauterine fetal diagnostic testing.

TARGET POPULATION

Women with chronic viral infections who are pregnant or planning a pregnancy.

OPTIONS

Non-invasive screening tests for diagnosis: maternal serum placental analytes with or without nuchal translucency, sonography, maternal serum cell-free placental DNA; and intrauterine fetal diagnostic testing: amniocentesis, chorionic villus sampling, cordocentesis.

OUTCOMES

The recommendations in this guideline have the potential to decrease or eliminate morbidity and mortality in women with chronic viral infections and their infants, which is associated with significant health and economic outcomes.

EVIDENCE

Published literature was retrieved through searches of PubMed, guidelines of national societies (Society of Obstetricians and Gynaecologists of Canada, American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine, other international societies), and the Cochrane Library using appropriate controlled vocabulary (amniocentesis, chorionic villus sampling, cordocentesis, procedure pregnancy loss risk, viral vertical transmission, fetal and neonatal infection) and keywords (maternal infection or exposure, hepatitis B, hepatitis C, human immunodeficiency virus). Results were restricted to systematic reviews, randomized controlled trials or controlled clinical trials (if available), and observational case-control studies or case series from 2012 to 2019 published in English or French. Studies from 1966 to 2002 were previously reviewed in the SOGC guideline No. 123: Amniocentesis and Women with Hepatitis B, Hepatitis C, or Human Immunodeficiency Virus, and those from 2002 to 2012 were previously reviewed in the SOGC guideline No. 309: Prenatal Invasive Procedures in Women With Hepatitis B, Hepatitis C, and/or Human Immunodeficiency Virus Infections. Updated literature searches were completed regularly through August 2019 and were incorporated into this guideline.

VALIDATION METHODS

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

The intended users are maternity care providers and women with chronic viral infections. This guideline provides information to educate and counsel these women, and to offer them reproductive options. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Directive clinique no 409 : Tests diagnostiques fœtaux intra-utérins en cas d'infection virale chronique maternelle

OBJECTIF

La présente directive clinique révisée met à jour les renseignements sur la prestation de soins aux femmes atteintes d'une infection virale chronique devant se soumettre à un test diagnostique fœtal intra-utérin.

POPULATION CIBLE

Femmes atteintes d'une infection virale chronique qui sont enceintes ou prévoient le devenir.

OPTIONS

Tests de dépistage non invasifs à des fins diagnostiques : marqueurs placentaires sériques maternels avec ou sans mesure de la clarté nucale, échographie, ADN fœtal libre circulant dans le sang maternel; et tests diagnostiques fœtaux intra-utérins : amniocentèse, biopsie choriale (choriocentèse), cordocentèse.

ISSUES

Les recommandations de la présente directive clinique pourraient réduire ou éliminer la morbi-mortalité chez les femmes atteintes d'une infection virale chronique et leurs nourrissons, ce qui est associé à d'importantes conséquences sur les plans de la santé et de l'économie. DONNéES PROBANTES: La littérature publiée a été recueillie au moyen de recherches dans les bases de données PubMed et Cochrane Library ainsi que dans les directives cliniques de sociétés médicales nationales et internationales (Société des obstétriciens et gynécologues du Canada, American College of Obstetricians and Gynecologists, Society for Maternal-Fetal Medicine et d'autres sociétés internationales) en utilisant un vocabulaire (amniocentesis, chorionic villus sampling, cordocentesis, procedure pregnancy loss risk, viral vertical transmission, fetal and neonatal infection) et des mots clés (maternal infection or exposure, hepatitis B, hepatitis C, human immunodeficiency virus) contrôlés et appropriés. Les résultats retenus se limitent aux revues systématiques, aux essais cliniques randomisés ou aux essais cliniques comparatifs (si disponibles) et aux études cas-témoins observationnelles ou études de série de cas publiées entre 2012 et 2019 en anglais ou en français. Les études publiées entre 1966 et 2002 ont déjà été examinées dans la directive clinique de la SOGC n^o 123, L'amniocentèse chez les femmes infectées par l'hépatite B, l'hépatite C ou le virus de l'immunodéficience humaine; les études publiées entre 2002 et 2012 ont quant à elles été examinées dans la directive clinique de la SOGC n^o 309, Interventions effractives prénatales chez les femmes qui présentent des infections par le virus de l'hépatite B, le virus de l'hépatite C et/ou le virus de l'immunodéficience humaine. De nouvelles recherches ont été effectuées dans la littérature jusqu'en août 2019, puis ont été intégrées à la présente directive clinique. MéTHODES DE VALIDATION: L'auteur a évalué la qualité des données probantes et la solidité des recommandations au moyen du cadre méthodologique GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Consulter l'annexe A en ligne (le tableau A1 pour les définitions et le tableau A2 pour les interprétations des recommandations fortes et faibles). PUBLIC VISé: Les utilisateurs prévus sont des fournisseurs de soins de maternité et les femmes atteintes d'une infection virale chronique. Cette directive fournit des renseignements pour renseigner et conseiller ces femmes et leur offrir des options de procréation. RECOMMENDATIONS (GRADE RATINGS IN PARENTHESES).

Acute Perinatal Infection and the Evidenced-Based Risk of Intrauterine Diagnostic Testing: A Structured Review

BACKGROUND

The prevalence of perinatal infection from maternal exposure is increasing. The prevalence of acute maternal infections identifies cytomegalovirus, parvovirus B19, toxoplasmosis, and varicella as the most common organisms and in the order of frequency. Maternal informed consent and understanding is required before intrauterine testing for fetal infectious and possible genetic risk assessment.

METHODS

This structured review of the reproductive published literature focuses on the risks of amniocentesis and cordocentesis diagnostic procedure-related fetal loss rates and fetal vertical transmission (VT) rates from published infected pregnant cohorts.

RESULTS

The total postprocedure fetal loss rate for diagnostic amniocentesis procedures, in limited infectious cohorts, is 1.5% and does not appear to be increased compared to "noninfected" amniocentesis cohorts using an estimated background spontaneous fetal loss rate (no procedure) of 0.65%. The "pooled" unintended fetal loss rate is from small infected population cohorts, but can be used for counseling purposes. Postcordocentesis fetal loss risk, in an infected cohort, is not possible to estimate due to limited data. The "biological spontaneous fetal loss rate" risk with a perinatal infection (positive or negative fetal anomalies) and no diagnostic procedure before 20 weeks of gestation is reviewed. The risk of VT in acute infection cohorts as a result of the intra-amniotic diagnostic procedure is not found to be increased.

CONCLUSION

The unintended "fetal loss" rate after amniocentesis for perinatal infected cohorts is similar to that of noninfected cohorts, but the estimate is based on limited infected cohorts. There was no procedure-based risk of fetal VT in the infected cohorts, but identification of postprocedure maternal bleeding into the amniotic cavity increases the potential risk. Maternal knowledge translation and an informed consent process with risk-benefit maternal/fetal risk counseling are required prior to any diagnostic amniocentesis procedure.

[Hepatitis B and pregnancy. Part 1. Thirteen practical issues in antenatal period]

In France, the prevalence of chronic hepatitis B is about 1% in pregnant women (usually asymptomatic carriers of HBsAg). The risk of maternal-fetal transmission of hepatitis B is particularly high when viral load measured by PCR is higher in mothers (above 7 log) or HBeAg is present. In case of maternal-fetal transmission of hepatitis B, the risk to the newborn of developing subsequent chronic hepatitis B is very high (90%), with long-term complications such as cirrhosis and hepatocellular carcinoma. The prevention of maternal-fetal transmission is based on systematic testing for hepatitis B during pregnancy, followed by serovaccination of the newborn at birth. If necessary, amniocentesis can be realised but will avoid the realization of a transplacental gesture. In case of high viral load, the establishment of a maternal antiviral treatment with lamivudine or tenofovir from 28SA can further reduce the risk of transmission. Given the low resistance it induces, tenofovir should be used preferentially.

Incidence of fetal bradycardia and effect of placental injury on fetal heart rate during second-trimester genetic amniocentesis

A prospective study was conducted for comparing the incidence of fetal bradycardia and level of fetal heart rate change following a second-trimester genetic amniocentesis with and without placental injury. A total of 257 and 495 participants in injured and non-injured groups were analysed. The incidence of fetal bradycardia following amniocentesis was not statistically different between the two groups (1.17%, [95% CI 0.24, 3.37] and 0.20%, [95% CI 0.005, 1.12]) in injured and non-injured placenta groups, respectively; p = 0.118). The mean change in baseline fetal heart rate before and after amniocentesis was also not significantly different between the two groups (p = 0.844). No fetal death or pregnancy loss occurred within 4 weeks after the procedure. All 4 bradycardia participants were normal and healthy and had an appropriate weight for their gestational age. We conclude that placental injury during a second-trimester genetic amniocentesis due to advanced maternal age poses only a low risk of fetal bradycardia, and there is no evidence of differences between subjects with injured and non-injured placenta in the changes in fetal heart rate.

Prenatal invasive procedures in women with hepatitis B, hepatitis C, and/or human immunodeficiency virus infections

OBJECTIVE

To review the risk of in utero infection through prenatal invasive procedures in women with hepatitis B, hepatitis C, and/or human immunodeficiency virus (HIV) infections.

OUTCOMES

Fetal and neonatal morbidity and mortality.

EVIDENCE

Published literature was retrieved through searches of Medline, CINAHL, and the Cochrane Library using appropriate controlled vocabulary (amniocentesis, chorionic villus sampling, cordocentesis, fetal and neonatal infection) and key words (hepatitis B, hepatitis C, HIV). Results were restricted to systematic reviews, randomized control trials/controlled clinical trials, and observational studies from 2002 to 2012 published in English or French. (Studies from 1966 to 2002 were previously reviewed in Clinical Practice Guideline No. 123.) Searches were updated on a regular basis and incorporated in the guideline to February 2014. Grey (unpublished) literature was identified through searching the websites of health technology assessment and health technology-related agencies, clinical practice guideline collections, clinical trial registries, and national and international medical specialty societies.

VALUES

The quality of evidence in this document was rated using the criteria described in the Report of the Canadian Task Force on Preventive Health Care (Table). Recommendations 1. For women infected with hepatitis B, hepatitis C, and/or human immunodeficiency virus, the use of non-invasive methods of prenatal risk assessment is recommended, using tests with high sensitivity and low false-positive rates, such as serum screening combined (or not) with nuchal translucency, anatomic ultrasound, and non-invasive molecular prenatal testing. (III-B) 2. For women infected with hepatitis B, hepatitis C, and/or human immunodeficiency virus undergoing an amniocentesis, every effort should be made to avoid inserting the needle through, or very close to, the placenta. (II-2B) 3. Little information is available on other prenatal diagnostic and therapeutic invasive procedures; the risks and benefits of such procedures should therefore be assessed prior to their use. (III-C) 4. The rate of neonatal hepatitis B infection attributable to amniocentesis ranges up to 1.4% in newborns of mothers positive for hepatitis B surface antigen. However, the rate of neonatal infection attributable to amniocentesis in newborns of mothers with a positive hepatitis B e antigen status may be as high as 16%. Although there is no statistically significant difference between the rates of infection in newborns exposed to amniocentesis or not exposed to amniocentesis in these two maternal populations, knowledge of the mother's hepatitis B e antigen status may be valuable in counselling women about the risks associated with amniocentesis. (II-2A) 5. Amniocentesis in women infected with hepatitis C does not appear to significantly increase the risk of vertical transmission, but women should be counselled that very few studies have properly addressed this possibility (II-2C). More research on this topic is recommended. (III-L) 6. Amniocentesis in women infected with human immunodeficiency virus on combination antiretroviral therapy does not appear to significantly increase the risk of vertical transmission, particularly if the viral load is undetectable, but women should be counselled that data on this issue is limited. (II-2B) 7. For women not on combined antiretroviral therapy, the risk of vertical transmission is increased by performing an amniocentesis. When possible, combined antiretroviral therapy should be initiated and the procedure postponed until the viral load is undetectable. Other case management should be individualized in consultation with infectious diseases specialists and obstetricians. (III-B).

Amniocentesis in HIV pregnant women: 16 years of experience

The iatrogenic risk of HIV vertical transmission, calculated in initial epidemiologic studies, seemed to counterindicate invasive prenatal diagnosis (PND) procedures. The implementation of highly active antiretroviral therapy (HAART) represented a turning point in PND management, owing to a rapid and effective reduction of maternal viral load (VL). In the present study, we identified cases of vertical transmission in HIV-infected pregnant women who did amniocentesis in the second trimester of pregnancy (n = 27), from 1996 to 2011. We divided our sample into Group A—women under HAART when submitted to amniocentesis (n = 20) and Group B—women without antiretroviral therapy before amniocentesis (n = 7). We had 1 case of vertical transmission in Group B. Preconceptional or early first trimester HIV serology is essential to avoid performing an amniocentesis without antiretroviral therapy or viral suppression. When there is an indication for amniocentesis in an HIV-infected pregnant woman, it should be done if the patient is on HAART and, if possible, when VL is undetectable. Nowadays, with combined first trimester screening test to select pregnancies with high risk of aneuploidies, advanced maternal age is a less frequent indication to perform PND invasive procedures, representing an outstanding gain in prenatal diagnosis of this population.

[Amniocentesis and viral risk (hepatitis B, C virus and HIV)]

Very few studies have properly addressed to the risk of fetal hepatitis B (HBV), hepatitis C (HCV) or human immunodeficiency virus (HIV) infection through amniocentesis. For HBV, this risk is low. However, knowledge of the maternal hepatitis B e antigen status is valuable in the counselling of risks associated with amniocentesis. For HCV, the risk is not well known but cannot be excluded. For HIV, it seems rational to propose a viral test before amniocentesis for patients with contamination's risk and to postpone the sampling in cases with positive results in order to obtain an undetectable HIV-1 RNA viral load. For these reasons, it can be useful to analyse for each virus the benefit of amniocentesis and the risk of mother-to-infant transmission, and to inform the patient.

Amniotic fluid fetal hemoglobin in normal pregnancies and pregnancies complicated with preterm labor or prelabor rupture of membranes

OBJECTIVE

Hemoglobin and its catabolic products have been associated with amniotic fluid (AF) discoloration and intra-amniotic infection/inflammation (IAI). However, the origin of AF hemoglobin (maternal or fetal) has not been determined. The aims of this study were to determine if fetal hemoglobin can be detected in AF obtained from normal pregnancies, and whether there is an association between AF fetal hemoglobin concentrations and gestational age, spontaneous labor (term and preterm), preterm prelabor rupture of membranes (PPROM) and IAI.

STUDY DESIGN

This cross-sectional study included pregnant women in the following groups: (1) mid-trimester (n = 60); (2) term not in labor (n = 21); (3) term in labor (n = 47); (4) spontaneous preterm labor with intact membranes (PTL) without IAI who delivered at term (n = 89); (5) PTL without IAI who delivered preterm (n = 74); (6) PTL with IAI (n = 78); (7) PPROM with (n = 48) and (8) without IAI (n = 48). AF fetal hemoglobin concentrations were determined by ELISA. Non-parametric statistics were used for analyses.

RESULTS

(1) Fetal hemoglobin was detected in 80.4% of all AF samples; (2) women at term not in labor had a higher median AF fetal hemoglobin concentration than those at mid-trimester (p = 0.008); (3) labor at term was not associated with a significant difference in the median AF fetal hemoglobin concentration; (4) the median AF fetal hemoglobin concentration was not significantly different among the three PTL groups or between the PPROM groups; (5) women with PTL and IAI had a lower AF fetal hemoglobin percentage of the total hemoglobin than those without IAI who delivered preterm (p = 0.03) or at term (p < 0.001); (6) The median AF fetal hemoglobin concentration was higher in pregnancies complicated with PTL or PPROM than in women at term (p < 0.001 for all comparison).

CONCLUSIONS

(1) The concentration of immunoreactive AF fetal hemoglobin increases with gestational age; (2) the median AF fetal hemoglobin concentration is higher in pregnancies complicated with PTL or PPROM than in term pregnancies; (3) among women with PTL or PPROM, the AF fetal hemoglobin concentrations were not associated with IAI; (4) however, women with PTL and IAI had a lower percentage of AF fetal hemoglobin of the total hemoglobin than those without IAI, suggesting different mechanisms of disease.

Amniocentesis and mother-to-child human immunodeficiency virus transmission in the Agence Nationale de Recherches sur le SIDA et les Hépatites Virales French Perinatal Cohort

OBJECTIVE

The objective of the study was to investigate whether performing an amniocentesis increased mother-to-child transmission of human immunodeficiency virus (HIV)-1 (MTCT).

STUDY DESIGN

We studied HIV -1 infected mothers and their children enrolled in the multicenter French Perinatal HIV Cohort from 1985 to 2006.

RESULTS

One hundred sixty-six amniocenteses were performed among 9302 singleton pregnancies, the proportion increasing from 1.0% before 2001 to 4.7% in 2005-2006. Use of highly active antiretroviral therapy (HAART) was more frequent in the amniocentesis group (58.4% vs 33.2%). MTCT tended to be higher in the amniocentesis group, among mothers who received no antiretroviral agents (25.0%; 3/12 vs 16.2%; 343/2113; P = .41) as well as among mothers receiving zidovudine monotherapy or a double-nucleoside reverse transcriptase inhibitor combination (6.1%; 3/49 vs 3.3%; 117/3556; P = .22), but the difference was not significant. Among 81 mothers receiving HAART, there was no case of MTCT.

CONCLUSION

Our results suggest that amniocentesis is not a major risk factor for mother-to-child transmission in mothers treated with effective antiretroviral therapy.

Total hemoglobin concentration in amniotic fluid is increased in intraamniotic infection/inflammation

OBJECTIVE

Discolored amniotic fluid (AF) has been associated with intraamniotic infection/inflammation (IAI) in patients with preterm labor (PTL). The presence of hemoglobin and its catabolic products has been implicated as a cause for AF discoloration. The aim of this study was to determine whether there is an association between total hemoglobin concentration in AF and gestational age, spontaneous labor (term and preterm), and the presence or absence of IAI.

STUDY DESIGN

This cross-sectional study included patients in the following groups: (1) mid trimester (n = 65 patients); (2) term not in labor (n = 22 patients); (3) term in labor (n = 47 patients); (4) spontaneous PTL who delivered at term (n = 92 patients); (5) PTL without IAI who delivered preterm (n = 76 patients); (6) PTL with IAI (n = 81 patients); (7) preterm prelabor rupture of the membranes (PPROM) with IAI (n = 48 patients); and (8) PPROM without IAI (n = 49 patients). Total hemoglobin concentrations in amniotic fluid were determined by an enzyme-linked immunoassay. Nonparametric statistics were used for analysis.

RESULTS

Hemoglobin was detected in all AF samples (n = 480). The median AF total hemoglobin concentration at term was significantly higher than in mid trimester (520.6 ng/mL [interquartile range (IQR), 271.2-1549.2] vs 58.5 ng/mL [IQR, 26.1-200.8]; P < .001]). Among patients with PTL, the median AF total hemoglobin concentration was significantly higher in patients with IAI than in patients without IAI (4671.7 ng/mL [IQR, 1294.2-8620.7] vs 2013.6 ng/mL [IQR, 629.2-5420.4]; P = .01) or women who delivered at term (1143.4 ng/mL [IQR, 451.8-4037.9]; P = .001). Similarly, among patients with PPROM, the median AF total hemoglobin concentration was significantly higher in patients with IAI than in patients without IAI (10753.7 ng/mL [IQR, 2053.9-56026.6] vs 2281 ng/mL [IQR, 938.2-9191.7]; P = .02). Women at term in labor had a higher median hemoglobin concentration than did women who were not in labor (1952.6 ng/mL [IQR, 709.6-6289.2] vs 520.6 ng/mL [IQR, 271.1-1549.2]; P = .003).

CONCLUSION

The AF concentration of immunoreactive total hemoglobin increases with advancing gestational age, and is elevated in pregnancies that are complicated with IAI. Spontaneous labor at term is associated with higher AF concentrations of total hemoglobin.

Amniocentesis in pregnant HIV-infected patients. Absence of mother-to-child viral transmission in a series of selected patients

OBJECTIVES

To assess the risk of vertical transmission in HIV-infected pregnant women undergoing diagnostic amniocentesis, and to identify possible predictive factors.

STUDY DESIGN

This was a single center retrospective study. The records of 330 HIV-infected pregnant women booked in our antenatal clinic from 31 January 2001 to 31 January 2006 were analyzed. Women who actually underwent diagnostic amniocentesis ("amniocentesis performed" group) were compared to those eligible for amniocentesis but who did not undergo the procedure ("amniocentesis withheld" group).

RESULTS

During the time period, 318 liveborn babies were delivered (9 HIV infected (2.8%)). Thirty-four women (35 fetuses) were eligible for diagnostic amniocentesis. Amniocentesis was performed in 11 (32.4%) of these women (12 fetuses, none infected among the 9 liveborns) and withheld in 23 (67.6%) women. Among the 19 liveborn babies in this latter group, 1 (5.3%) was infected. There was no statistical difference in vertical transmission rate between the whole cohort of HIV-infected pregnant women and the group of women eligible for amniocentesis; or between the women who actually had or did not have an amniocentesis. The women who did undergo amniocentesis all received highly active antiretroviral combination therapy with three drugs; all but two had an undetectable HIV viral load, only one had immunosuppression and none had HCV co-infection.

CONCLUSION

No vertical transmission was observed in a group of nine liveborn babies after amniocentesis performed in selected HIV-infected pregnant women. In the presence of high genetic risk during pregnancy, amniocentesis can be considered after proper patient counselling.

Fatal fetal hemorrhage and placental pathology. Report of three cases and a new setting

We report three cases of late third trimester fetal death in utero consequent to fetal exsanguination from the chorionic vasculature. In general, fetal hemorrhage is unusual, exsanguination is rare and the location and basis of the hemorrhage varies widely. Intragestational and intrapartum hemorrhage is far more often of maternal rather than fetal origin. Even when severe, the former is almost always manageable whilst the latter may be clinically obscure, intractable, catastrophic and fatal. In this presentation, we review and characterize fetal hemorrhage by anatomical location and on the basis of its underlying origins. In our first two cases, the chorionic vascular failure is understood on the basis of mechanical factors, such as tearing by the presenting part or an amniotomy hook. Our third case demonstrates the first reported instance in which a severe chorionic vasculopathy has damaged a placental surface vessel sufficiently to permit spontaneous rupture and fetal exsanguination.

Amniocentesis and women with hepatitis B, hepatitis C, or human immunodeficiency virus

OBJECTIVE

To review the risk of in utero infection through amniocentesis in women with hepatitis B, hepatitis C, or human immunodeficiency virus (HIV).

OUTCOMES

Fetal and neonatal morbidity and mortality.

EVIDENCE

Review articles, meta-analyses, and MEDLINE searches from 1966 to 2002 for English-language articles related to amniocentesis, fetal and neonatal infection, and hepatitis B, hepatitis C, or HIV.

VALUES

The evidence collected was reviewed by the Genetics Committee of the Society of Obstetricians and Gynaecologists of Canada (SOGC) and quantified using the Evaluation of Evidence guidelines developed by the Canadian Task Force on the Periodic Health Exam.

RECOMMENDATIONS

1. The risk of fetal hepatitis B infection through amniocentesis is low. However, knowledge of the maternal hepatitis B e antigen status is valuable in the counselling of risks associated with amniocentesis. (II-1C) 2. Amniocentesis in women infected with hepatitis C does not appear to significantly increase the risk of vertical transmission, but women should be counselled that very few studies have properly addressed this possibility. (II-2C) 3. In HIV-positive women all noninvasive screening tools should be used prior to considering amniocentesis. (II-2D) 4. For women infected with hepatitis B, hepatitis C, or HIV, the addition of noninvasive methods of prenatal risk screening, such as nuchal translucency, triple screening, and anatomic ultrasound, may help in reducing the age-related risk to a level below the threshold for genetic amniocentesis. (II-2C) 5. For those women infected with hepatitis B, hepatitis C, or HIV who insist on amniocentesis, every effort should be made to avoid inserting the needle through the placenta. (II-1B) VALIDATION: These guidelines have been approved by the SOGC Genetics Committee, SOGC Executive, and SOGC Council.

SPONSORS

The Society of Obstetricians and Gynaecologists of Canada.

Detection of hepatitis C virus RNA (HCV RNA) in amniotic fluid: a prospective study

BACKGROUND/AIMS

Mother-to-infant transmission of hepatitis C virus (HCV) has been reported, but the transmission route is unknown. The aim of our study was to detect HCV RNA in amniotic fluid of pregnant women seropositive for HCV.

METHODS

Twenty-two HCV seropositive women were included in the study (median age: 39 years). An amniocentesis was performed in all patients during the 4th month of pregnancy. Sixteen women also tested positive for HCV RNA in serum. The range of HCV RNA titers was 0.3 to 15.1x10(6) Eq/ml (Quantiplex HCV RNA 2.0 Assay, Chiron Diagnostics). Of these 16 viremic patients, four had an anterior placenta, ten had a posterior placenta and the position of the placenta was not determined in two cases. PCR (Amplicor HCV, Roche Diagnostics) was used to detect HCV RNA in the amniotic fluid. We also studied 11 HCV seronegative women as a control group.

RESULTS

In the viremic group (n = 16), HCV RNA was detected once in amniotic fluid. The positive specimen was collected from a patient with an HCV RNA serum value equal to 1.1x10(6) Eq/ml. The placenta was in an anterior position. A PCR inhibitor was detected in one case. No HCV RNA was detected in the amniotic fluid of six seropositive non-viremic patients, nor in the control group. Serum HCV RNA was negative in the ten children tested. The woman whose amniotic fluid contained HCV RNA was the mother of one of them.

CONCLUSIONS

HCV RNA detection in amniotic fluid is rarely positive. The anterior position of the placenta in the only positive detection cannot rule out contamination of the amniotic fluid during the transplacental amniocentesis.