Neuroimaging and neurodevelopmental outcome after early fetal growth restriction: NEUROPROJECT-FGR.

BACKGROUND: Adverse neurodevelopmental outcomes and MRI alterations are reported in infants born after fetal growth restriction (FGR). This study evaluates the additional role of FGR over prematurity in determining brain impairment. METHODS: Retrospective observational study comparing 48 FGR and 36 appropriate for gestational age infants born between 26 and 32 weeks' gestation who underwent a cerebral MRI at term equivalent age. Exclusion criteria were twins, congenital anomalies, and findings of overt brain lesions. Main outcomes were total maturation score (TMS) and cerebral areas independently measured by two neuro-radiologists and Griffiths or Bayley scale III scores at median age of 2 years. RESULTS: TMS was not significantly different between the groups. Inner calvarium and parenchyma's areas were significantly smaller in FGR cases. There were no significant differences in the average quotient scores. A positive correlation between parenchyma area and cognitive score was found (r = 0.372, p = 0.0078) and confirmed after adjusting for sex, gestational age, and birth weight (p = 0.0014). Among FGR, the subgroup with umbilical arterial Doppler velocimetry alterations had significantly worse gross motor scores (p = 0.005). CONCLUSIONS: FGR plays additional role over prematurity in determining brain impairment. An early structural dimensional MRI evaluation may identify infants who are at higher risk. IMPACT: Fetal growth-restricted infants showed smaller cerebral parenchymal areas than preterm controls. There is a positive correlation between the parenchyma area and the cognitive score. These results highlight the already known link between structure and function and add importance to the role of a structural dimensional MRI evaluation even in the absence of overt brain lesions.

Differences between influenza and pertussis vaccination uptake in pregnancy: a multi-center survey study in Italy.

BACKGROUND: A suboptimal maternal vaccination coverage in 2017-18 has been reported in Italy. The study aims were to (i) assess changes in maternal influenza and tetanus, diphtheria and acellular pertussis vaccination coverage during 2018-19 influenza season compared to the previous season (ii) estimate influenza vaccine coverage among maternal care providers (MCPs) and (iii) explore the characteristics of vaccine delivery to pregnant women. METHODS: We conducted a cross-sectional survey among pregnant women and MCPs about influenza and pertussis immunization during pregnancy. We also collected information regarding prenatal care characteristics and vaccine delivery among four centers in Italy. RESULTS: We recruited 483 pregnant women and 452 MCPs. The influenza and pertussis vaccine uptake among pregnant women for the season 2018-19 was 14.9% and 60.9%, respectively. MCPs' influenza vaccine uptake was 33.6%. Knowing that the flu vaccine was safe for mothers and their infants and being vaccinated in the previous influenza season were associated with higher vaccine uptake. Regarding pertussis, being a housewife was associated to lower vaccine uptake, while knowing the vaccine is effective and safe for mothers and newborns were associated with higher pertussis vaccine uptake. The single most important factor associated to higher coverage of both influenza and pertussis vaccines was receiving a health-care provider's vaccine advice. Most pregnant women (69.4%) stated that they preferred to be vaccinated in their same prenatal care setting. CONCLUSIONS: Receiving a health-care provider's vaccine advice and the availability of vaccines during prenatal care visits might improve vaccination coverage among pregnant women.

Impact of the COVID-19 Pandemic on Prenatal Care Utilization Among Italian and Immigrant Pregnant Women: A Multicenter Survey.

Objectives: To compare the utilization of prenatal services between immigrant and Italian women during the COVID-19 pandemic. Methods: A cross-sectional survey was conducted at 3 maternity care centers in Italy. Results: We included 1,312 women, 1,198 (91.3%) were Italian and 114 (8.7%) were immigrants. A significantly higher proportion of Italians underwent 8 or more prenatal care visits (64.4% vs. 54.4%, p = 0.03) and more immigrants than Italians attended their appointments at hospital settings (45% vs. 18%, p < 0.001). Regarding prenatal course, Italians were more likely than immigrants to attend a non-hospital setting or an online class (49.6% and 30.2% vs. 34.9% and 11.6%, p = 0.008). A higher influenza vaccine uptake among immigrants compared with Italians was observed (39.5% vs. 19.8%, p < 0.001). Among women not receiving certain prenatal services, immigrants were more likely to state COVID-19 pandemic was the main reason for non-compliance. Conclusion: Immigrant pregnant women were more likely to receive prenatal services at a hospital setting than their Italian counterparts. Among women who did not comply with prenatal services, immigrants were more likely to cite the pandemic as their main reason.

SARS-CoV-2 Vaccine Uptake during Pregnancy in Regione Lombardia, Italy: A Population-Based Study of 122,942 Pregnant Women.

Italy has been one of the hardest hit countries in the European Union since the beginning of the SARS-CoV-2 pandemic, and Regione Lombardia (RL) has reported the largest number of cases in the country. This population-based retrospective study analyzed RL records of 122,942 pregnant women to describe SARS-CoV-2 vaccination uptake in the pregnant population, to compare pregnant women vaccine uptake vs. women of childbearing age and to evaluate the impact of vaccination status in pregnant women on admissions to intensive care units during 2021. Vaccination uptake according to citizenship and educational level and the comparison between pregnant and non-pregnant women was performed by Z test. A logistic regression was performed to compare age groups. Out of 122,942 pregnant women, 79.9% were vaccinated at the end of 2021. The vaccine uptake rate was significantly lower in pregnant versus non-pregnant women but increased after the issuing of official recommendations. Vaccine administration was significantly higher among pregnant women with Italian citizenship and with a high level of education in all trimesters. In conclusion, the role of official recommendations with explicit communication about the importance and safety of vaccination in pregnancy is critical to obtain trust and acceptance among pregnant women.

Perinatal and 2-year neurodevelopmental outcome in late preterm fetal compromise: the TRUFFLE 2 randomised trial protocol.

INTRODUCTION: Following the detection of fetal growth restriction, there is no consensus about the criteria that should trigger delivery in the late preterm period. The consequences of inappropriate early or late delivery are potentially important yet practice varies widely around the world, with abnormal findings from fetal heart rate monitoring invariably leading to delivery. Indices derived from fetal cerebral Doppler examination may guide such decisions although there are few studies in this area. We propose a randomised, controlled trial to establish the optimum method of timing delivery between 32 weeks and 36 weeks 6 days of gestation. We hypothesise that delivery on evidence of cerebral blood flow redistribution reduces a composite of perinatal poor outcome, death and short-term hypoxia-related morbidity, with no worsening of neurodevelopmental outcome at 2 years. METHODS AND ANALYSIS: Women with non-anomalous singleton pregnancies 32+0 to 36+6 weeks of gestation in whom the estimated fetal weight or abdominal circumference is <10th percentile or has decreased by 50 percentiles since 18-32 weeks will be included for observational data collection. Participants will be randomised if cerebral blood flow redistribution is identified, based on umbilical to middle cerebral artery pulsatility index ratio values. Computerised cardiotocography (cCTG) must show normal fetal heart rate short term variation (≥4.5 msec) and absence of decelerations at randomisation. Randomisation will be 1:1 to immediate delivery or delayed delivery (based on cCTG abnormalities or other worsening fetal condition). The primary outcome is poor condition at birth and/or fetal or neonatal death and/or major neonatal morbidity, the secondary non-inferiority outcome is 2-year infant general health and neurodevelopmental outcome based on the Parent Report of Children's Abilities-Revised questionnaire. ETHICS AND DISSEMINATION: The Study Coordination Centre has obtained approval from London-Riverside Research Ethics Committee (REC) and Health Regulatory Authority (HRA). Publication will be in line with NIHR Open Access policy. TRIAL REGISTRATION NUMBER: Main sponsor: Imperial College London, Reference: 19QC5491. Funders: NIHR HTA, Reference: 127 976. Study coordination centre: Imperial College Healthcare NHS Trust, Du Cane Road, London, W12 0HS with Centre for Trials Research, College of Biomedical & Life Sciences, Cardiff University. IRAS Project ID: 266 400. REC reference: 20/LO/0031. ISRCTN registry: 76 016 200.

Efficacy of 4.0 mg versus 0.4 mg Folic Acid Supplementation on the Reproductive Outcomes: A Randomized Controlled Trial.

Folic acid (FA) supplementation prevents neural tube defects (NTDs), but the effects on other reproductive outcomes are unclear. While common recommendation is 0.4 mg/day in addition to regular nutrition, the most appropriate dose of FA is still under debate. We investigated the effects of a higher dose of periconception FA on reducing adverse reproductive outcomes. In this multicenter double-blind randomized controlled trial (RCT), 1060 women (aged 18-44 years and planning a pregnancy) were randomly assigned to receive 4.0 mg or 0.4 mg of FA daily. The primary outcome was the occurrence of congenital malformations (CMs). A composite outcome including one or more adverse pregnancy outcomes was also evaluated. A total of 431 women had a natural conception within 1 year. The primary outcome occurred in 8/227 (3.5%) women receiving 4.0 mg FA and 9/204 (4.4%) women receiving 0.4 mg FA (RR 0.80; 95%CI 0.31 to 2.03). The composite outcome occurred in 43/227 (18.9%) women receiving 4.0 mg FA and 75/204 (36.8%) women receiving 0.4 mg FA (RR 0.51; 95%CI 0.40 to 0.68). FA 4.0 mg supplementation was not associated with different occurrence of CMs, compared to FA 0.4 mg supplementation. However, FA 4.0 mg supplementation was associated with lower occurrence of other adverse pregnancy outcomes.

Barriers and facilitators regarding influenza and pertussis maternal vaccination uptake: A multi-center survey of pregnant women in Italy.

OBJECTIVE: In 2017, the Italian Ministry of Health issued the new 2017-19 National Plan of Vaccine Prevention and pregnant women were targeted to be vaccinated against influenza and pertussis. Our study aim was to assess the barriers and facilitators regarding maternal immunization acceptance among pregnant women after the launch of this program. STUDY DESIGN: We conducted a multi-center survey in three Italian cities between March and June 2018. Collected data were analyzed anonymously, and included information about current recommendations of maternal immunization, antenatal care characteristics and reasons for accepting or rejecting vaccination. RESULTS: A total of 743 pregnant women completed the survey. Half of the study population were aged 25-35 years and 88 % were Italian. Only 18 % pregnant women received advice to be vaccinated. In this group, the vaccine was recommended in most cases by an obstetrician-gynecologist (68 %) and during a routine antenatal visit (74 %). Self-reported influenza and pertussis vaccination coverage was 6.5 % (95 % confidence interval, 4.9 %-8.5 %) and 4.8 % (95 % confidence interval, 3.5 %-6.6 %), respectively. The main vaccination barriers identified were lack of vaccine recommendation by any health-care provider (81 %) and safety concerns (18 %). Respondents mentioned the willingness to protect their offspring (82 %) and themselves (66 %) and having received immunization advice by a maternal care provider (62 %), as the main vaccination facilitators. CONCLUSIONS: Lack of immunization advice by health-care providers and safety concerns were the main vaccination barriers against influenza and pertussis, among surveyed pregnant women. Vaccine delivery in the antenatal care setting could lead to increase of vaccine acceptance among pregnant women.

First-trimester itraconazole exposure and pregnancy outcome: a prospective cohort study of women contacting teratology information services in Italy.

BACKGROUND: Itraconazole is an effective fungal treatment; however, there are few human data on prenatal exposure. OBJECTIVES: To evaluate the major malformation rate in itraconazole prenatally exposed infants. The secondary objective includes evaluation of the pregnancy outcome. METHODS: A prospective cohort study was conducted from January 2002 to October 2006 in women who called two Italian Teratology Information Services (TIS). Pregnant women who were exposed to itraconazole during the first trimester and gave informed consent were matched with a contemporary group of pregnant women who contacted the TIS because they had undergone a non-teratogenic drug exposure during the first trimester. Information was obtained via a structured questionnaire at the time of the initial call to the TIS and no earlier than 1 month after delivery. A trained operator conducted the interview. The main outcome measure was information about major congenital anomalies, type of delivery, birth weight, and any pregnancy or neonatal complications. RESULTS: Data were collected on 206 women who called the TIS because of first-trimester exposure to itraconazole, and 207 controls. There were no significant differences in terms of major congenital anomalies in the exposed group versus the control group (3/163 [1.8%] vs 4/190 [2.1%], respectively). There was no statistical difference in the rate of vaginal delivery between the exposed and control groups (101/162 [62.3%] vs 102/190 [53.8%]), premature birth (11/162 [6.8%] vs 15/190 [7.9%]), low birth weight (1/152 [0.7%] vs 4/175 [2.3%]) and high birth weight (10/152 [6.5%] vs 7/175 [4.0%], respectively). The rates of live births (163/206 [79.1%] vs 190/207 [91.8%]), spontaneous abortion (23/206 [11.2%] vs 10/207 [4.8%]) and termination of pregnancy (19/206 [9.2%] vs 7/207 [3.4%] in the exposed and control groups, respectively) were significantly different (p < 0.05). CONCLUSION: First-trimester itraconazole-exposed infants were not at increased risk of major congenital anomalies, but the rates of spontaneous and induced abortion were higher in the exposed group versus the control group. Larger studies are warranted to confirm these observations.

Determination of daptomycin in human plasma and breast milk by UPLC/MS-MS.

During the lactation, the choice of a proper antibiotic is crucial since the drug can cross into breast milk causing toxicity to the infant. Therefore, an extraction protocol and LC/MS-MS method for the determination of daptomycin in human milk and plasma were developed, validated and applied to a case of a breastfeeding mother affected by a purulent acute soft skin infection treated with daptomycin. Because of daptomycin high protein binding and its high molecular weight, the optimisation of the extraction protocol and analytical conditions were deeply investigated, and several parameters were taken into account: in particular the type of extraction, internal standard, the type of organic modifier, pH of the aqueous solution, and gradient. The use of a protein precipitation protocol coupled to a C8-reverse phase LC-MS/MS allows for a reliable quantification of daptomycin in both plasma (in the range of 19-199 µg/mL) and breast milk (in the range of 0.12-0.32 µg/mL). The determination of milk/plasma (M/P) ratio, which ranged from 0.002 to 0.006, allowed to assess that daptomycin, effective for the mother, was contemporarily safe for the breastfed newborn.

Paternal exposure and counselling: experience of a Teratology Information Service.

We describe paternal exposure and counselling in a selected population calling to an Italian Teratology Information Service (TIS). The majority of callers asked for paternal drug exposure (76%, drugs except chemotherapy) and treatment for cancer (17%, chemotherapy and/or radiotherapy). Others asked for exposure to diagnostic radiations (4%), recreational drugs (2%) and occupational chemicals (1%). Among paternal drugs neurological compounds, immunosuppressive drugs and antiviral agents were the main reasons for calling. In humans, there are no evidences of birth defects after paternal exposures, but to minimize any possible risk, counselling in men exposed to radio and chemotherapy should recommend delaying conception for at least 3 months after the end of the therapy. Male patients treated with drugs, whose teratogenic potential has been well assessed or suspected for maternal exposure, should be advised to practice effective birth control during therapy and up to one or two cycles of spermatogenesis and to avoid semen contact with vaginal walls during first trimester of pregnancy.

Pregnancy outcome in women exposed to antiepileptic drugs: teratogenic role of maternal epilepsy and its pharmacologic treatment.

Infants born to epileptic women treated with antiepileptic drugs (AEDs) have an increased risk of major congenital malformations (MCMs). In order to determine the role of maternal epilepsy we conducted a prospective cohort study on three cohorts of pregnant women: (i) 385 epileptic women treated with AEDs, (ii) 310 non-epileptic women treated with AEDs, (iii) 867 healthy women not exposed to AEDs (control group). The rate of MCMs in the epileptic group (7.7%) was not statistically higher than in the non-epileptic one (3.9%) (p=0.068). The rate in the first group was higher compared to the control group (p=0.001), while the rate in the second one was not (p=0.534). Our data confirm that AEDs therapy is the main cause of the increased risk of malformations in the offspring of epileptic women; however a teratogenic role of the maternal epilepsy itself cannot be excluded.

Antiepileptic drugs during pregnancy: pharmacokinetics and transplacental transfer.

Epilepsy represents the most common maternal neurological disorder requiring continuous treatment during pregnancy. Maintaining optimum seizure control is an important objective in pregnancy, and the majority of women with epilepsy will need to continue antiepileptic drugs (AEDs). AEDs are frequently used to treat several other conditions, such as headaches and mood disorders. They have been associated with an increased risk of congenital malformations, minor anomalies, congenital syndrome and development disorders. This risk seems to be higher among women using polypharmacy and valproic acid. Neural tube defects are associated with valproic acid and carbamazepine exposure. New AEDs seem to have a less teratogenic effect, but human experience is still limited. The purpose of this review is to provide an update on AED exposure in pregnancy, focusing on pharmacokinetics and transplacental transport.

Smoke, alcohol consumption and illicit drug use in an Italian population of pregnant women.

OBJECTIVE: High-risk behaviours are associated with an increased risk of adverse pregnancy outcomes. Exposure to drugs, infection or radiation is a cause of concern for pregnant women, who contact Teratology Information Services (TIS) to have a counseling but with an accurate medical history is possible to detect additional behavioural risk factors that can significantly interfere with pregnancy outcome. The aim of this study is to describe risk behaviours in a population of Italian women calling our TIS and to identify related maternal factors. STUDY DESIGN: Between December 2008 and January 2010 we collected data from 503 pregnant women calling our TIS (Telefono Rosso, Rome). We investigated about smoke, alcohol and abuse substances addiction and we also collected demographic data. RESULTS: Of the 503 women consenting to participate 34% were found to have an additional risk marker during the current pregnancy. Within this group were 22.7% (n=119) who reported smoking, the 17.7% (n=89) admitted to drink and 2 women (0.4%) used illicit drugs. In 13.7% of cases (n=69) reason for calling represented an exposure to teratogenic agents. Unmarried status and previous induced abortion represent a risk factor for all high-risk behaviours. Lower education (p<0.001) and use of neurological drugs (p<0.001) are related with cigarette consumption. A lower parity was a risk factor for alcohol assumption (p=0.04). Women with high-risk behaviours tend to be exposed to more than a risk factor. CONCLUSIONS: Teratogen Information Services are an important system to identify women with pregnancy risk markers. These services should have the ability to provide risk reduction information to women who smoke cigarettes or with alcohol or drug use. In addition to the phone based information these women may benefit from referral back to their physician for assessment and management of substance use/abuse during pregnancy. Substance abuse risks are often underestimated by pregnant women. Single mothers or women with an history of terminations of pregnancy represents an high-risk population. Physicians should inform their patients about possible risks related to high-risk behaviours during preconception counseling or during the first obstetric visit.

Clopidogrel treatment during pregnancy: a case report and a review of literature.

Management of ischemic heart disease in pregnant women is still difficult, as there is little experience with many of the newer treatments such as clopidogrel. The safety of clopidogrel in pregnancy is unknown, especially in combination with aspirin. Its use during gestation has been described in a few case reports. We describe the case of a 36-year-old woman in her 9th week of pregnancy with a history of chronic hypertension, dyslipidemia and CAD, who required antiplatelet treatment. Clopidogrel and aspirin were administrated until one week before delivery and a healthy child was born at 36 weeks of pregnancy by caesarean section, without any complication.

Use of the Internet by women seeking information about potentially teratogenic agents.

OBJECTIVE: The aim of this study was to evaluate if the Internet provides evidence-based information to women seeking information about teratogenic risk factors and women's risk perception. Furthermore, we evaluated the possible risk related to teratogen exposure in the study sample and analysed age, gravidity, educational level, geographic location, marital status and type of exposure compared to a control group made up of women who did not use the Internet to search for teratogen-related information. STUDY DESIGN: Between October 2008 and June 2009, a questionnaire was administered to pregnant women calling our Teratology Information Service concerning a suspected teratogenic exposure. RESULTS: Fifty-seven percent (n=116) of callers had used the Internet to find medical information about their exposure, while 43% (n=87) had not. Internet users had a medium-high level of education and consulted the Internet because of its convenience, usually early in their pregnancy. We verified the accuracy of the information the women obtained from the Internet and found that 59.5% (n=69) of women received evidence-based answers; 18.1% (n=21) were informed that their exposure was dangerous when it was not; 4.3% (n=5) were wrongly reassured; and the rest (n=18) were not able to interpret the data they found or found no relevant information. CONCLUSIONS: Internet use during pregnancy is a widespread phenomenon as the Internet offers the opportunity to share apprehensions and doubts with other women, but it can often lead to increased and unjustified anxiety. Medical information published on websites cannot be considered a substitute for informed medical advice, and patients should not take any action before consulting with a health care professional.

First trimester diclofenac exposure and pregnancy outcome.

OBJECTIVE: To assess the safety of diclofenac during pregnancy. METHODS: A prospective observational cohort study, evaluating follow-up data of women who contacted Teratology Information Services to get counseling. The exposed group included 145 pregnant women who were exposed to diclofenac between the 5th and the 14th gestational week. A contemporary control group (501 women) was randomly selected from among patients who contacted Teratology Information Services with regard to exposures to agents known not to be teratogenic during a similar period of pregnancy. RESULTS: Major birth malformations were not more common in the study group than in the control group (p=0.07). CONCLUSION: Our study suggests that the use of diclofenac is relatively safe during the first trimester of pregnancy and the studied sample size makes it possible to exclude a risk of congenital malformation higher than 3.3, with a power of 80%.

Prenatal drug exposure and teratological risk: one-year experience of an Italian Teratology Information Service.

BACKGROUND: Concern about exposure to drugs, radiation, or infection during pregnancy occur often because pregnancy is not always planned. A teratology information service offers rapid scientific counseling to all those worried about prenatal exposure. The aim of this study is to present data on the most common pharmaceutical products responsible for teratogenic risk in the one-year experience of a teratology information service in Italy. MATERIAL/METHODS: The survey was conducted among 8664 callers who contacted our Teratology Information Service in Rome between January and December 2006. Data on maternal age, gravidity, parity, maternal health status, and details of exposure (dose and timing) were collected and stored in a specific data base. Scientific counseling on prenatal exposure was given to the caller by a specialized service operator, specifying the type of risk and suggesting appropriate tests for prenatal diagnosis. RESULTS: Most of the people called regarding drug exposure; increased risk was present in only 5% of the pregnant women calling during pregnancy. Selective serotonin reuptake inhibitors (SSRIs) are the first category that are actually considered of increased risk to the fetus. The second category is represented by antiepileptic drugs. CONCLUSIONS: This experience confirms previous data that there is a high teratological risk perception among both women and physicians. The drugs estimated to present increased risk are medications used for chronic neurological diseases, mainly mood disorders and epilepsy. Preconceptional counseling for these women could be an effective strategy to prevent such exposure and to improve maternal and fetal outcome.

Radiation effects on development.

It has been widely reported that prenatal exposure to ionizing radiation can interfere with embryonic and fetal development, depending on dose and gestational age in which exposure occurs. According to several studies on animal models, different well-defined stages during prenatal life can be distinguished in relation to teratogenic effects. During the preimplantation stage, elevated doses of radiation can result in abortion, while lower doses may produce genomic damage that is usually repaired. On the other hand, during the organogenesis stage in mice (embryonic day 6.5 [E6.5] to E13.5), irradiation is associated with increased incidence of malformation and intrauterine growth restriction (IUGR). Later exposure is linked to brain damage. Doses used in animal studies are generally higher than those used for diagnostic procedures in humans. Usually, radiation exposure to diagnostic range (<0.05 Gy = 5 rads) is not associated with an increased risk of congenital anomalies. In human studies, elevated doses produce adverse outcomes, depending on stage of development, as in animal studies. Blastogenesis (up to two weeks) is associated with failure to implant or no significant health effects. An increased risk of malformation and growth retardation can be observed for two to seven weeks exposure (organogenesis stage), while exposure at later stages (fetogenesis) is mainly associated with brain damage. In this review we focus on the relevance of estimating the cumulative dose of radiation to the fetus and the gestational age in which exposure occurs, to provide appropriate counseling to pregnant women.

The intracoelomic route: a new approach for in utero human cord blood stem cell transplantation.

The intracoelomic route for in utero hematopoietic stem cell transplantation has been evaluated in pre-immune fetal sheep and the engraftment characteristics defined. Twelve ovine fetuses (gestational ages: 40-45 days) received intracoelomic transplants of human CD3-depleted (50 x 10(6) per lamb) or CD34-selected (1-2 x 10(5) per lamb) cord blood hematopoietic stem cells. Engraftment was evaluated from cell suspension of the liver, spleen, bone marrow and thymus by flow cytometry, cloning assays and polymerase chain reaction (PCR) analysis for human beta(2)-microglobulin gene. The engraftment of liver samples was also evaluated by reverse transcriptase-polymerase chain reaction (RT-PCR), fluorescent in situ hybridization (FISH) and immunohistochemistry. Four fetuses (33%) aborted shortly after intracoelomic transplantation and were not evaluable for engraftment. Engraftment was detected in 4 fetuses obtained from cesarean delivery on day 70 after transplantation of CD3-depleted cord blood cells. The degree of engraftment in these 4 fetuses ranged from 6 to 22% in the different organs (as revealed by antigenic analysis of human CD45 with flow cytometry). Three fetuses obtained after cesarean section at 102 (No. 435184) and 105 (Nos 915293, 037568) days and 1 fetus delivered at term, which received CD34-selected cord blood cells, had human engraftment with 10, 32, 20 and 10% CD45+ cells in bone marrow, respectively. A further check of human chimerism was done at 1 year after birth of the fetus delivered at term and 7.6% of bone marrow chimerism was detected. In 6 out of 8 fetuses evaluable for human engraftment, chimerism was confirmed by PCR analysis for human beta(2)-microglobulin which also identified human cells in brain, spinal cord, heart, lung and skeletal muscle. On liver samples, FISH and RT-PCR confirmed the xenograft of human cells and the immunohistochemical analysis detected human markers of hematopoietic and hepatic lineage of differentiation. This preliminary study indicates that intracoelomic transplantation of human hematopoietic stem cells in fetal lambs is feasible and effective in terms of hematopoietic engraftment.