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Purpose: Several studies investigated endometrial patterns, with respect to pregnancy rates following the transfer of embryos but did not distinguish between single- and multiple-blastocyst procedures. We clarified how the endometrial pattern imaged to transfer a frozen embryo is associated with pregnancy outcomes in single-blastocyst frozen-embryo transfer (sbFET). Methods: Patients ≤35 years who underwent sbFET on the hormone replacement protocol. We analyzed endometrial patterns' associations with pregnancy outcomes in relation to blastocyst grade and pregnancy-related factors. Results: Of the 1383 cycles, 483 were Lf, 840 were partial-Lf, and 60 were non-Lf. Leaf pattern (Lf): central echogenic line present and continuous. Overall, decreasing distinctness of the central echogenic line was associated with significantly lower rates of clinical pregnancy (Lf: 70.4%; partial-Lf: 58.1%; non-Lf: 28.3%) and live birth (56.3%, 45.5%, and 15.0%) and a higher miscarriage rate (20.0%, 21.7%, and 47.1%). Logistic regressions showed pregnancy and live birth to be significantly more likely and miscarriage less likely in Lf than non-Lf: OR (95% CI): 6.07 (3.24-11.37), 7.43 (3.47-15.39), and 0.20 (0.07-0.57). Conclusions: Non-Lf presentation was associated with lower rates of pregnancy and live birth, suggesting it signals unsuitable conditions for embryo transfer. We provide information on the pregnancy outcomes of sbFET for endometrial patterns.
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Purpose: To evaluate clinical outcomes after endometrial receptivity analysis (ERA). Methods: This was a multicenter, retrospective cohort study involving 861 women who underwent ERA testing at certified fertility clinics in Japan, and who received subsequent personalized blastocyst embryo transfers (ET) between 2018 and 2020. Clinical outcomes, including pregnancies, miscarriages, and live births, were evaluated according to receptivity status for ERA. Results: Mean patient age was 37.7 years (SD = 4.0), and the median number of previous ETs was 2 (interquartile range, 2-3). 41.0% (353/861) of patients were non-receptive for ERA testing. Clinical pregnancy, miscarriage, and live birth rates for personalized blastocyst ET were 44.5% (226/508), 26.1% (59/226), and 26.8% (136/508) for receptive patients, and 43.1% (152/353), 28.3% (43/152), and 28.9% (102/353) for non-receptive patients, all statistically nonsignificant. Multiple logistic regression demonstrated similar nonsignificant associations between receptivity and clinical outcomes. Greater patient age, smoking, and longer duration of infertility were significantly and negatively associated with receptivity, whereas a history of delivery was positively associated and statistically significant. Conclusions: Clinical outcomes after ERA testing were similar between receptive and non-receptive patients. Further prospective study including an appropriate comparison group are warranted to evaluate the efficacy of ERA testing.
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AIM: To assess the impact of breast-cancer treatment on fertility. METHODS: We conducted a retrospective, case-based survey of treatments administered for infertility and pregnancy outcomes after patients underwent treatment for breast cancer. Surveys were distributed to breast oncology facilities and reproductive endocrinology and infertility (REI) facilities. RESULTS: As high as 60% of the pregnancies in women under the age of 35 years occurred spontaneously. Additionally, the fertility rates decreased as age increased (under 35 years of age: 40%, 35-39 years of age: 21%, 40-44 years of age: 10%, respectively). In women who became pregnant after treatment for breast cancer, conception was achieved within 1 to 3 years after beginning to try for pregnancy. CONCLUSIONS: After treatment for breast cancer, women can expect spontaneous pregnancy, especially if they are under 35 years of age. It is important for patients 35 years of age and older to commence assisted reproductive technology in a timely manner when pursuing fertility after treatment for breast cancer.
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Neoplasias da Mama , Preservação da Fertilidade , Infertilidade , Adulto , Neoplasias da Mama/terapia , Feminino , Fertilidade , Humanos , Japão , Gravidez , Estudos RetrospectivosRESUMO
RESEARCH QUESTION: Does the inclusion of three antioxidants (A3), acetyl-l-carnitine (ALC), N-acetyl-l-cysteine (NAC) and alpha-lipoic acid (ALA) improve human embryo development and pregnancy potential? DESIGN: Prospective randomized multicentre comparison of sibling oocytes. A total of 1563 metaphase II oocytes from 133 patients in two IVF centres. Day 3 embryo and day 5/6 blastocyst quality were assessed. Good embryo quality on day 3 was defined as 8 to 10 cells with even cells and low fragmentation; good quality blastocysts as 3BB or greater. Clinical outcome was assessed on transfers of fresh or vitrified-warmed blastocyst on day 5. RESULTS: Of the two-pronuclei, 40.7% (G-Series) and 50.2% (G-Series with A3 group) resulted in good quality embryos on day 3 (P < 0.05). The implantation rate by fetal sac was 39.2% and 50.6%, and by fetal heartbeat was 37.8% and 47.1% for the G-Series and G-Series with A3 group, respectively. When stratified by female patient age, patients 35-40 years had an implantation rate by fetal sac and heart of 23.5% in the G-Series compared with 57.5% (P < 0.05) and 50.0% (P < 0.05) in the A3 group. The ongoing pregnancies in patients 35-40 years were significantly higher in the A3 group (50%) compared with the control (25.8%) (P < 0.05). CONCLUSIONS: The presence of antioxidants during IVF and embryo culture for patients 35-40 years resulted in a significant increase in implantation and pregnancy rate. Supplementation of antioxidants to IVF and culture media may therefore improve the viability of human embryos in assisted reproductive technologies, plausibly through the reduction of oxidative stress.
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Antioxidantes/análise , Meios de Cultura/química , Técnicas de Cultura Embrionária/métodos , Desenvolvimento Embrionário/fisiologia , Fertilização in vitro/métodos , Oócitos , Acetilcarnitina/análise , Acetilcisteína/análise , Adulto , Transferência Embrionária/métodos , Feminino , Humanos , Gravidez , Taxa de Gravidez , Estudos Prospectivos , Ácido Tióctico/análiseRESUMO
AIM: This retrospective cohort study evaluated the effectiveness of injury to the endometrium prior to the frozen-thawed embryo transfer (FET) cycle in patients with repeated implantation failure (RIF) in our clinic. METHODS: Included in this study were 173 patients, aged ≤ 41 years, who failed to become pregnant after repeating fair and/or good embryo transfer more than twice between February 2012 and February 2015. The patients were divided into three groups: Group A (n = 38) underwent soft curettage to the endometrium twice, prior to the FET cycle; Group B (n = 45) underwent hysteroscopy prior to the FET cycle, with no significant factors, such as endometrial polyp; and Group C (n = 90) was the no-treatment group. RESULTS: The clinical pregnancy rate per transfer was found to be statistically significant between Group A at 42.1% (16/38) and Group C at 22.2% (20/90). The crude and adjusted odds ratios (OR) were 2.55 and 2.49 (95% confidence intervals 1.13-5.78, P = 0.03 and 1.01-6.17, P = 0.048) respectively. Group B with only hysteroscopy had a higher pregnancy rate of 35.6% (16/45) than Group C, but showed no statistical significance (P = 0.103). CONCLUSION: These results suggest that injuring the endometrium has a positive effect on pregnancy.
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Transferência Embrionária/métodos , Endométrio/lesões , Taxa de Gravidez , Aborto Espontâneo , Adulto , Curetagem , Implantação do Embrião , Endométrio/diagnóstico por imagem , Feminino , Humanos , Histeroscopia , Gravidez , Estudos RetrospectivosRESUMO
Aim: Outside of Japan, recombinant-human chorionic gonadotropin (r-hCG) is widely used for the induction of final follicular maturation and early luteinization in women undergoing ovulation induction; whereas in Japan, urine-derived hCG (u-hCG) is predominantly used. The primary objective of this study was to demonstrate the non-inferiority of r-hCG to u-hCG for ovulation induction, as assessed by the ovulation rate. Methods: This was an open-label, parallel-group, randomized, multicenter, phase III trial in Japanese women with anovulation or oligo-ovulation secondary to hypothalamic-pituitary dysfunction or polycystic ovary syndrome, undergoing ovulation induction with recombinant-human follicle-stimulating hormone. The women were randomized (2:1) to receive either a single 250 µg s.c. dose of r-hCG or a single 5000 IU i.m. dose of u-hCG for ovulation triggering. Results: Eighty-one women were randomized to either r-hCG (n=54) or u-hCG (n=27). Ovulation occurred in 100% of the participants and treatment with r-hCG was observed to be non-inferior to u-hCG for ovulation induction. Overall, the type and severity of adverse events were as expected for women receiving fertility treatment. Conclusion: This study demonstrated that r-hCG was non-inferior to u-hCG for inducing ovulation. Furthermore, r-hCG demonstrated an expected safety profile, with no new safety concerns identified.
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PURPOSE: To assess the efficacy of a novel, defined vitrification procedure using recombinant human albumin (rHA) for cryopreservation of human blastocysts. DESIGN: Retrospective study. SETTING: Private IVF clinic. PATIENTS: 1,496 patients received vitrified/warmed embryo transfer (ET). METHODS: Surplus blastocysts, and blastocysts from patients undergoing elective embryo cryopreservation, were vitrified/warmed using Cryotop carriers in homemade solutions containing either human serum albumin (HSA) or rHA. MAIN OUTCOME MEASURES: Clinical and neonatal outcomes regarding the vitrified/warmed ET procedures. RESULTS: The HSA and rHA groups had a total of 1,163 and 898 vitrified/warmed cycles, respectively. Embryo survival rates (98.7% vs. 98.9%, respectively) and the number of embryos transferred (1.08 ± 0.01 vs. 1.06 ± 0.01, respectively) were similar in the HSA and rHA groups. Clinical pregnancy rates/ET were higher (P < 0.05) in the rHA group (56.0%) than in the HSA group (51.5%). The HSA and rHA groups had similar live delivery rates/pregnancy (72.2% vs. 72.3%, respectively) and perinatal outcomes, including birth weight (2,988 ± 28 vs. 3,046 ± 26 g, respectively). Birth defects occurred in 0.9% and 1.6% of neonates in the HSA and rHA groups, respectively. CONCLUSIONS: rHA effectively replaced HSA for human embryo vitrification procedures, and yielded high rates of pregnancy and live births after vitrified/warmed ET. This new approach will support the development of defined ART systems, which will eliminate the variation and risks associated with the use of blood-derived products.
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Albuminas/administração & dosagem , Blastocisto/metabolismo , Criopreservação , Proteínas Recombinantes/administração & dosagem , Albuminas/genética , Peso ao Nascer , Blastocisto/química , Transferência Embrionária/métodos , Feminino , Humanos , Recém-Nascido , Nascido Vivo , Gravidez , Taxa de Gravidez , Proteínas Recombinantes/genética , Vitrificação/efeitos dos fármacosRESUMO
OBJECTIVE: Assisted reproductive technology (ART), especially frozen-thawed embryo transfer (FET) in a hormone replacement cycle (HRC), is a risk factor for placenta accreta spectrum (PAS). This study aimed to clarify the risk factors for PAS related to the maternal background and ART techniques in pregnancies achieved after FET in an HRC. STUDY DESIGN: We performed a case-control study in two tertiary perinatal centres in Japan. Among 14,028 patients who delivered at ≥24 weeks of gestation or were transferred after delivery to two tertiary perinatal centres between 2010 and 2021, 972 conceived with ART and 13,056 conceived without ART. PAS was diagnosed on the basis of the FIGO classification for the clinical diagnosis of PAS or retained products of conception after delivery at ≥24 weeks of gestation. We excluded women with fresh embryo transfer, FET with a spontaneous ovulatory cycle, a donor oocyte cycle, and missing details of the ART treatment. Finally, among women who conceived after FET in an HRC, 62 with PAS and 340 without PAS were included in this study. Multivariate logistic regression models were used for case-control comparisons, with adjustment for maternal age at delivery, parity, endometriosis or adenomyosis, the number of previous uterine surgeries of caesarean section, myomectomy, endometrial polypectomy or endometrial curettage, placenta previa, the stage of transferred embryos, and endometrial thickness at the initiation of progestin administration. RESULTS: PAS was associated with ≥2 previous uterine surgeries (adjusted odds ratio, 3.57; 95 % confidence interval, 1.60-7.97) and the stage of embryo transfer (blastocysts: adjusted odds ratio, 2.89; 95 % confidence interval, 1.15-7.26). In patients with <2 previous uterine surgeries, PAS was associated with an endometrial thickness of <7.0 mm (adjusted odds ratio, 5.18; 95 % confidence interval, 1.10-24.44). CONCLUSION: Multiple uterine surgeries and the transfer of blastocysts are risk factors for PAS in pregnancies conceived after FET in an HRC. In women with <2 previous uterine surgeries, a thin endometrium before FET is also a risk factor for PAS in these pregnancies.
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Placenta Acreta , Gravidez , Feminino , Humanos , Placenta Acreta/etiologia , Estudos de Casos e Controles , Cesárea , Transferência Embrionária/métodos , Progestinas , Criopreservação/métodos , Fatores de Risco , Estudos RetrospectivosRESUMO
OBJECTIVE: Abdominal trachelectomy (AT) is a fertility-preservation surgery for patients with early-stage cervical cancer. Few studies have reported the outcomes of assisted reproductive technology (ART) in patients after AT. The aim of this study was to evaluate the outcomes of ART after AT. STUDY DESIGN: In this retrospective study, we compared the ART outcomes of 13 patients who underwent AT at another hospital prior to undergoing ART at our clinic (T group) and 52 control patients (non-T group) who did not undergo AT prior to ART, selected on the basis of age, time of treatment onset, and serum anti-Müllerian hormone concentrations, matched 1:4, respectively. RESULTS: Cumulative live birth rates were 62% (8/13) and 65% (34/52) in the T and non-T groups, respectively (p = 0.795). The total number of oocyte retrieval cycles was 34 in the T group and 95 in the non-T group. In all oocyte retrieval cycles, no significant differences were noted in the number of oocyte retrievals, rate of fertilization, and presence of good-quality blastocysts (Gardner classification ≥ BB). The total number of embryo transfer (ET) cycles was 55 in the T group and 109 in the non-T group. The pregnancy and live birth rates per ET were lower in the T group than those in the non-T group (pregnancy rate, 20% vs. 39%, p = 0.017; live birth rate, 15% vs. 30%, p = 0.028; respectively). Endometrial thickness before ET was lower in the T group vs. the non-T group: median (range): 7.4 (3.5-14.3) mm vs. 9.0 (5.5-14.9) mm, respectively; p < 0.0001. Multivariate logistic regression models showed that age at oocyte retrieval (adjusted odds ratio [OR], 0.76; 95% confidence interval [CI], 0.66-0.87), use of good-quality blastocysts (adjusted OR, 3.23; 95% CI, 1.20-8.67), and history of AT (adjusted OR, 0.28; 95% CI, 0.11-0.72) were associated with the pregnancy rate per ET. CONCLUSION: The pregnancy rate per ET was lower in patients with vs. without a history of AT. Clinicians should be aware of the longer time to pregnancy in patients who undergo ART after AT.
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Traquelectomia , Gravidez , Humanos , Feminino , Taxa de Gravidez , Estudos Retrospectivos , Nascido Vivo/epidemiologia , Técnicas de Reprodução Assistida , Transferência Embrionária , Fertilização in vitroRESUMO
Background: Transfer of more than one embryo following in vitro fertilization/intracytoplasmic sperm injection cycles have increased pregnancy rate at the cost of increasing the incidence of triplets and twins. It has been proposed that prolonged culture to the blastocyst stage would automatically result in the selection of good quality embryos for transfer and minimize the incidence of triplets and twins. Methods and Results: The objectives of the present retrospective analysis were to examine the pregnancy outcome, multiple pregnancy and related data following: (i) single blastocyst transfer (BT) and double BT; (ii) single BT in patients belonging to different age groups; and (iii) good, fair or poor quality of BT. A total of 260 BT were carried out between August 1998 and July 2002 and they are included in the current study. Sixty of the 260 BT patients received a single BT, and 41 of them received selected single good quality BT (SSBT). The implantation rate has no significant difference between following single BT (53.3%) and double BT (42.8%). No multiple pregnancy occurred following single BT, while significantly higher (P < 0.05) multiple pregnancy rate was observed following a double BT (45.8%). The clinical pregnancy and implantation rates following a single BT were similar (P > 0.05) in patients belonging to <30 years (62.5%), 30-34 years (57.9%) and 35-39 years old (35.8%). Conclusion: Selected single good quality BT maintained pregnancy and avoided multiple pregnancies. It is recommended for patients with a risk for high-order multiple pregnancy. (Reprod Med Biol 2004; 3: 13-18).
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OBJECTIVE: To evaluate the implications of assisted reproductive technologies (ART) on neonatal birth weight. DESIGN: A retrospective study using analysis of covariance and multiple logistic regression analysis of the Japanese ART registry. SETTING: Japanese institutions providing ART treatment. PATIENT(S): A total of 25,777 singleton neonates reaching term gestation following ART during the years 2007-2008, with 11,374 achieved through fresh embryo transfers (fresh ET) and 14,403 achieved through frozen-thawed embryo transfers (FET). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Birth weight. RESULT(S): The mean birth weight after FET was significantly higher compared with fresh ET and all Japanese births (3,100.7 ± 387.2 g, 3,009.8 ± 376.8 g, and 3,059.6 ± 369.6 g, respectively). The risk for low birth weight in FET was significantly lower compared with fresh ET. In fresh ET, ovarian stimulations were associated with about twofold risk of low birth weight compared with natural cycle. Regarding to the duration of embryonic culture, the risks resulting from a shorter culturing time were significantly higher compared with a longer culturing time in fresh ET. CONCLUSION(S): The best method of embryo transfer for fetal growth was FET after extended culturing until blastocyst stage. However, further investigations should be performed to understand the safety of ART treatment.
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Peso ao Nascer , Recém-Nascido de Baixo Peso , Infertilidade/epidemiologia , Infertilidade/terapia , Resultado da Gravidez/epidemiologia , Sistema de Registros , Técnicas de Reprodução Assistida/estatística & dados numéricos , Feminino , Humanos , Recém-Nascido , Japão/epidemiologia , Masculino , Gravidez , Prevalência , Fatores de RiscoRESUMO
We evaluated our clinical data on refrozen-thawed ETs (92 cycles) and found that human embryos were capable of withstanding two freeze-thaw cycles, resulting in normal live births after transfer at a rate similar to that of primary frozen-thawed embryos. This is the first follow-up study to present perinatal outcomes of children born after embryo re-cryopreservation, and our results should encourage clinicians to explore the possibility of performing the refreezing procedure.
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Blastocisto , Criopreservação , Transferência Embrionária , Fertilização in vitro , Reaquecimento , Adulto , Distribuição de Qui-Quadrado , Técnicas de Cultura Embrionária , Transferência Embrionária/efeitos adversos , Feminino , Humanos , Japão , Nascido Vivo , Pessoa de Meia-Idade , Gravidez , Taxa de Gravidez , Estudos Retrospectivos , Reaquecimento/efeitos adversos , Medição de Risco , Fatores de Risco , Resultado do Tratamento , Adulto JovemRESUMO
OBJECTIVE: To present the effectiveness of intracytoplasmic sperm injection (ICSI) using globozoospermic sperm and assisted oocyte activation by electrical stimulation. DESIGN: A case report. SETTING: A private IVF center in Japan. PATIENT(S): A man with globozoospermia. INTERVENTION(S): Acridine orange (AO) test, mouse oocyte activation test, and ICSI with electrical oocyte activation. MAIN OUTCOME MEASURE(S): Fertilization, pregnancy, and live birth. RESULT(S): In the first ICSI attempt, neither of the two injected oocytes fertilized. Staining of the patient's sperm with AO showed that only 2.9% of the sperm emitted a green fluorescence at the characteristic round head (sperm with native DNA content). The mouse oocyte activation test using the roundheaded sperm showed that the normal fertilization rate was 78.9% when SrCl(2) was used for assisted oocyte activation; however, it was 6.0% without assisted oocyte activation. We confirmed that the sperm had defective ability to activate oocytes. In the second ICSI attempt, human oocytes were activated electrically with use of a single square direct current pulse after microinjection. All the seven injected oocytes fertilized normally, and two eight-cell embryos were transferred on day 3. Clinical pregnancy was confirmed, and a healthy girl weighing 2362 g was delivered at 37 weeks of gestation by cesarean section. CONCLUSION(S): This is the first successful outcome of ICSI using globozoospermic sperm and electrical oocyte activation. The electroactivation obviates the need for the use of potentially harmful drugs for activation.
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Estimulação Elétrica , Fertilização in vitro/métodos , Oócitos/fisiologia , Resultado da Gravidez , Injeções de Esperma Intracitoplásmicas , Espermatozoides/anormalidades , Adulto , Animais , Feminino , Humanos , Recém-Nascido , Infertilidade Masculina/terapia , Masculino , Camundongos , Oócitos/citologia , Gravidez , Interações Espermatozoide-ÓvuloRESUMO
BACKGROUND: Although lipofection-induced TNF-alpha can activate nuclear factor kappaB (NF-kappaB), which, in turn, increases the transgene expression from plasmid DNA in which any NF-kappaB responsive element is incorporated, no attempts have been made to use such biological responses as NF-kappaB activation against a vector to enhance vector-mediated gene transfer. METHODS: A lipoplex composed of N-[1-(2,3-dioleyloxy)propyl]-N,N,N-trimethylammonium and cholesterol liposome and plasmid DNA encoding firefly luciferase under the control of the cytomegalovirus immediate early promoter (pCMV-Luc) was intravenously injected into mice. Luciferase activity as well as NF-kappaB activation in the lung were evaluated. Then, a novel plasmid DNA, pCMV-kappaB-Luc, was constructed by inserting 5 repeats of NF-kappaB-binding sequences into the pCMV-Luc. RESULTS: NF-kappaB in the lung was activated by injection of the lipoplex and its nuclear localization was observed. An injection of lipopolysaccharide 30 min prior to the lipofection further activated NF-kappaB. At the same time, the treatment significantly increased the transgene expression by lipoplex, suggesting a positive correlation between expression and NF-kappaB activity. Based on these findings, we tried to enhance the lipoplex-based transgene expression by using NF-kappaB activation. The lipoplex consisting of pCMV-kappaB-Luc showed a 4.7-fold increase in transgene expression in the lung compared with that with pCMV-Luc. CONCLUSIONS: We demonstrated that NF-kappaB activation by lipoplex can be used to enhance lipoplex-mediated transgene expression by inserting NF-kappaB-binding sequences into plasmid DNA. These findings offer a novel method for designing a vector for gene transfer in conjunction with biological responses to it.
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Regulação da Expressão Gênica/efeitos dos fármacos , Vetores Genéticos , Pulmão/metabolismo , NF-kappa B/metabolismo , Transgenes , Animais , Colesterol/metabolismo , Colesterol/farmacologia , Técnicas de Transferência de Genes , Lipossomos/administração & dosagem , Lipossomos/metabolismo , Lipossomos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Regiões Promotoras Genéticas/genética , Compostos de Amônio Quaternário/metabolismo , Compostos de Amônio Quaternário/farmacologia , Distribuição Tecidual , Transgenes/efeitos dos fármacos , Fator de Necrose Tumoral alfa/metabolismoRESUMO
Interferons (IFNs) exhibit pleiotropic biological activities that are considered to play important roles in tumor suppression and rejection. Therefore, IFN genes are promising for in vivo cytokine gene therapy targeted against tumors. In the present study, we evaluated the efficacy of hydrodynamics-based IFN gene transfer for tumor treatment, in which the naked pDNA encoding IFN-beta or IFN-gamma was administered into the tail vein of mice following portal vein (liver metastasis), tail vein (lung metastasis), or subcutaneous injection (subcutaneous tumor) of mouse colon carcinoma CT-26 cells. A substantial amount of IFN was soon markedly expressed in the liver and a transient increase in IFN activity was detected in the circulation. This procedure caused transgene-specific IFN production with little induction of other proinflammatory cytokines. In the liver metastasis experiment, the mice treated with IFN-expressing pDNA displayed a profound reduction in liver metastasis and a prolonged survival. Administration of the pDNA at an earlier stage of metastasis was more crucial for the antitumor effect. Similar tumor suppression was seen in the lung metastasis experiment. These therapeutic effects were more marked with IFN-beta-expressing pDNA treatment than with IFN-gamma-expressing pDNA treatment. On the other hand, subcutaneous CT-26 tumor growth was hardly affected by pDNA administration. These results suggest that the hydrodynamics-based transfer of naked pDNA is a convenient and efficient method of IFN gene therapy against metastatic tumors.