Association between estrogen receptor 1 (ESR1) and leukemia inhibitory factor (LIF) polymorphisms can help in the prediction of recurrent implantation failure.

OBJECTIVE: To investigate an association between polymorphisms related to the implantation process that together could help in the prediction of recurrent implantation failure (RIF). DESIGN: Cohort study. SETTING: Private fertility center and reproductive genetics laboratory. PATIENT(S): Forty-four women presenting RIF, who were included in study group (RIF group), and two control groups, one with 63 women who were attended at our service and became pregnant after the first IVF/intracytoplasmic sperm injection attempt (control group I) and other with 65 fertile women who had at least two children without any treatment and no history of miscarriage (control group II). INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genotyping was performed in the intron region of TP63, VEGFA, MMP2, ESR1, and ESR2 genes and in the 3' untranslated region of the LIF gene on genomic DNA using real-time polymerase chain reaction. RESULT(S): The presence of ESR1/AA (rs12199722) and LIF/GT (rs929271) genotypes was more frequent in the RIF group, leading to a 7.9-fold increase in the chance of women presenting with RIF when compared with women who became pregnant on their first cycle of IVF/intracytoplasmic sperm injection and a 2.8-fold increase when compared with women who became pregnant without treatment. CONCLUSION(S): The association between ESR1 and LIF polymorphisms can help in the prediction of RIF.

The TP73 gene polymorphism (rs4648551, A>G) is associated with diminished ovarian reserve.

It's known that the members of the TP53 family are involved in the regulation of female reproduction. Studies in mice showed that the TP73 gene (member of this family) plays a role in the size of follicular pool, ovulation rate and maintenance of genomic stability. In the present study we analyzed data from 605 patients with ≤ 37 years attending their first intracytoplasmic sperm injection (ICSI). The association between the TP73 polymorphism (rs4648551, A>G) and the following parameters related to ovarian reserve, like age, antral follicular count (AFC), anti-Mullerian hormone levels (AMH) and ovarian response prediction index (ORPI) was evaluated. Our results showed an association of the AA genotype with diminished ovarian reserve (AMH <1, AFC ≤9). Women presenting the AA genotype had a 2.0-fold increased risk for having AMH <1 and AFC ≤9 (OR 2.0, 95% CI 1.23-3.31, P = 0.005). Patients presenting AA genotype had the lowest levels of AMH (P = 0.02), the lowest number of antral follicles (P = 0.01) and the lowest ORPI (P = 0.007). Analyzing the alleles, we can see an enrichment of the A allele in the group of diminished ovarian reserve (OR 1.4, 95%CI 1.02-1.83, P = 0.04). To the best of our knowledge, the present study is the first to analyze this polymorphism in humans for assessing the numbers of ovarian follicles and AMH levels and, therefore, the ovarian reserve. Our findings can contribute to the use of this polymorphism as a potential marker of diminished ovarian reserve.

Day 2 vs. day 3 embryo transfer after intracytoplasmic sperm injection. A prospective, randomized study.

OBJECTIVE: To compare, in a prospective, randomized study, implantation and pregnancy rates between day 2 and day 3 embryo transfer intracytoplasmic sperm injection (ICSI). STUDY DESIGN: A total of 106 patients undergoing ICSI cycles who had at least 1 embryo suitable for cryopreservation were prospectively randomized into 2 groups: group I, embryo transfer performed on day 2; group II, embryo transfer performed on day 3. RESULTS: Patient ages did not differ (P = .58) between groups I (33.1 +/- 4.5) and II (32.7 +/- 4.4). The number of oocytes retrieved from group I (13.7 +/- 5.2) was similar (P = .82) to that retrieved from group II (13.7 +/- 5.4). In addition, there was no difference (P = .30) in the number of oocytes retrieved at metaphase II between groups I (10.6 +/- 4.4) and II (9.7 +/- 4.2). Fertilization and cleavage rates were also similar (P = .58 and P = .50, respectively) between groups I (78.2 +/- 14.0% and 98.7 +/- 4.3%) and II (76.2 +/- 14.8% and 99.8 +/- 1.24%, respectively). The total number of embryos and of embryos transferred were similar (P = .22 and P = .36; respectively) for groups I (8.0 +/- 3.0, 2.8 +/- 0.7) and II (7.16 +/- 3.2, 2.6 +/- 0.8). Pregnancy rates per transfer, implantation rates and abortion rates were also similar for groups I (43.4%, 20.8% and 8.7%, respectively) and II (41.5%, 24.1% and 23%, respectively) (P = 1.0, P = .57 and P = .24, respectively). CONCLUSION: The results suggest that extending the embryo culture period from 2 to 3 days for patients who had at least 1 embryo left for cryopreservation had no effect on implantation, pregnancy or abortion rates in an ICSI program.

Correlation between semen analysis by motile sperm organelle morphology examination and sperm DNA damage.

Regression analysis of 538 semen samples demonstrated that percentages of normal nuclear sperm and all spermatozoa with abnormalities of nuclear form at high magnification had significant negative correlation with percentages of DNA fragmentation. On the other hand, there was a positive correlation between percentages of spermatozoa with nuclear vacuoles and those with DNA fragmentation.

Recombinant luteinizing hormone supplementation to recombinant follicle-stimulation hormone during induced ovarian stimulation in the GnRH-agonist protocol: a meta-analysis.

PURPOSE: to compare the efficacy of recombinant LH supplementation for controlled ovarian stimulation in recombinant FSH and GnRH-agonist protocol. METHODS: Search strategies included on-line surveys of databases. The fixed effects model was used for odds ratio and effect size (weighted mean difference). Four trials fulfilled the inclusion criteria. RESULTS: a fewer days of stimulation (p<0.0001), a fewer total amount of r-FSH administered (p<0.0001) and a higher serum estradiol levels on the day of hCG administration (p<0.0001) were observed for the r-LH supplementation protocol. However, differences were not observed in number of oocyte retrieved, number of mature oocytes, clinical pregnancy per oocyte retrieval, implantation and miscarriage rates. CONCLUSIONS: more randomized controlled trials are necessary before evidence-based recommendations regarding exogenous LH supplementation in ovarian stimulation protocols with FSH and GnRH-agonist for assisted reproduction treatment can be provided.

Laser-assisted hatching of cryopreserved-thawed embryos by thinning one quarter of the zona.

Laser-assisted hatching is little documented in the literature regarding its efficacy in cryopreserved-thawed (CT) embryo transfer cycles. The aim of the present study was to evaluate in a randomized manner the efficacy of thinning one quarter of the zona pellucida of CT embryos to a depth of 50-80% of the original thickness, via laser treatment (the qLZT-AH procedure), in improving implantation and pregnancy rates. Two populations were studied: population I, patients who had all their supernumerary embryos cryopreserved, regardless of their morphology, and population II, patients at risk of ovarian hyperstimulation syndrome who had all their embryos cryopreserved. Artificial and natural protocols were used for the embryo transfers. A total of 350 laser-thinned CT embryos were compared with 352 intact zona embryos. No difference in implantation or pregnancy rate was found after using qLZT-AH in either population. These findings suggest that qLZT-AH should not be routinely performed in cryopreserved embryo programmes.

Effects of vaginal progesterone administration starting on the day of oocyte retrieval on pregnancy rates.

PURPOSE: Vaginal progesterone administration starting on the day of oocyte retrieval induced a decrease in uterine contraction frequency on the day of embryo transfer (ET) as compared with preovulatory values. Uterine relaxation before ET is likely to improve outcome by avoiding displacement of the embryo from the uterine cavity (Fanchin, Righini, de Ziegler, Oliviennes, Ledée, Frydman: Fertil Steril 2001;75:1136-1140). The objective of the present study was to determine whether the early use of vaginal progesterone on the day of oocyte retrieval may alter the embryo implantation and pregnancy rates. METHODS: A total of 103 patients were submitted for ovarian stimulation with GnRH-a and recombinant FSH (Puregon, Organon) for the application of invasive assisted reproduction techniques (ICSI). The patients were divided into two groups in a prospective and randomized manner: Group A (n = 51) where application of vaginal progesterone started (Utrogestan, Besins International) at the dose of 400 mg from the evening of the day of oocyte retrieval, and Group B (n = 52) started to apply vaginal progesterone at the same dose but from the evening of embryo transfer (2nd day). RESULTS: The age of Group A patients (34.2 +/- 4.6) was similar (p = 0.50) to that of Group B patients (34.8 +/- 4.9). The number of oocytes retrieved and at metaphase II from Group A patients (10.6 +/- 6.9 and 7.8 +/- 6.0; respectively) did not differ significantly (p = 0.84 and p = 0.49, respectively) from the number of oocytes retrieved and metaphase II from Group B patients (10 +/- 5.6 and 6.7 +/- 4.7, respectively). Also, there was no difference (p = 0.48) in number of embryos transferred to Group A patients (2.7 +/- 0.8) versus Group B patients (2.7 +/- 0.9). Embryo implantation and pregnancy rates for Group A patients (12.6 and 27.4%, respectively) were equal (p = 0.98 and p = 1.0, respectively) to those for Group B patients (13.4 and 28.8%, respectively). CONCLUSION: Vaginal progesterone at the dose of 400 mg started on the day of oocyte retrieval did not increase implantation or pregnancy rates when compared to the same dose started on the day of embryo transfer.

Psychological evaluation test for infertile couples.

PURPOSE: The infertility can lead to various emotional changes (anxiety, depression, somatization, aggressiveness, etc.). The objective of the present study was to develop a psychological evaluation test (PET) in an attempt to identify couples requiring psychological support when they face the problem of infertility. MATERIAL AND METHODS: A total of 251 infertile couples were submitted to the PET of the Center for Human Reproduction, "Sinhá Junqueira" Maternity Foundation. The causes of infertility were male-related in 45% of cases, female-related in 48%, and both male- and female-related in 7%. Infertility was primary in 74% of cases and secondary in 26%. The mean age of the women was 34 +/- 4.2 years and the mean age of the men was 36.8 +/- 6.5 years. The PET of the infertile couples was evaluated using a questionnaire with 15 questions selected in order to detect emotional reactions. The responses were assigned four grades with respect to frequency (1 = never or rarely; 2 = sometimes; 3 = many times, and 4 = always). The sum of the responses corresponded to a PET score ranging from 15 to 60 points. A PET score of >30 points was defined as cut-off point for necessity of specialized psychological evaluation. Data were analyzed statistically by the Student's t test and the Mann-Whitney and Fisher tests, with the level of significance set at 5%. The reliability of the questionnaires was determined on the basis of the alpha coefficient of Cronbach. RESULTS: The mean PET score for women (27 +/- 8) was significantly higher (p < 0.01, Mann-Whitney test) than the PET score for men (22 +/- 7). The alpha coefficient of Cronbach was 0.88, and was identical for the female and male questionnaires. CONCLUSIONS: The data demonstrate that one of the characteristics of Brazilian infertile couples is that women are habitually more affected by the situation of infertility than men. The PET is a simple and efficient tool for the identification of women and/or men requiring psychological support due to infertility. The team of the Center for Human Reproduction (employees, biologists, nurses, doctors etc.) has started to use the information provided by the PET in the daily routine, and all patients are informed and counseled about the factors generating emotional changes in infertility. Advice is provided (practicing sports, traveling, activating personal projects etc.) in order to help combat distress. A specialized psychological evaluation was indicated in selected cases (PET score >30 points).

Psychological evaluation test after the use of assisted reproduction techniques.

PURPOSE: The emotional changes provoked by the use of assisted reproduction techniques (ART) may trigger important psychological reactions. The objective of the present study was to develop a psychological evaluation test (PET-ART) in order to identify the occurrence of psychological problems and to facilitate their treatment. METHODS: A total of 128 women were submitted to PET-ART of the Center for Human Reproduction, "Sinhá Junqueira" Maternity Foundation, after application of IVF/ICSI program at least once. The causes of infertility were male-related in 45% of cases, female-related in 48%, and both male- and female-related in 7%. Infertility was primary in 79% of cases and secondary in 21%. The mean age of the women was 34.5 +/- 5.2 years and the mean age of the men was 37.9 +/- 6.8 years. The PET-ART was evaluated using a questionnaire with 15 questions selected in order to detect emotional reactions caused by infertility. The responses were assigned four grades with respect to intensity (1 = mild intensity; 2 = medium intensity; 3 = high intensity; and 4 = maximum or unbearable intensity). The sum of the responses corresponded to PET-ART score ranging from 15 to 60 points. The reliability of the questionnaire was evaluated by the alpha coefficient of Cronbach. RESULTS: The PET-ART identified five questions receiving 50% or more responses of the high/maximum intensity type (sum of the percentages of responses with a score of 3 and 4). The questions were the following: 1--The waiting time before being submitted to a pregnancy test (82.8% of the patients); 2--A negative result of the pregnancy test (77.3% of the patients); 3--The degree of anxiety in a new attempt to obtain pregnancy (76.5% of the patients); 4--Finding the money necessary for the repetition of the IVF/ICSI techniques (66.4% of the patients); 5--The possibility of collecting few eggs, or of forming or not an embryo in the laboratory is an expectation that makes me anxious (57.8% of the patients). The mean PET-ART was 33 +/- 6. The alpha coefficient of Cronbach was 0.757. CONCLUSIONS: The PET-ART was an efficient tool for the identification of women with emotional changes provoked by the application of ART and for the planning of their treatment. However, a general psychological approach was developed for each emotional factor regardless of PET-ART.

A uterine ultrasonographic scoring system as a method for the prognosis of embryo implantation.

PURPOSE: The objective of the present study was to evaluate an ultrasonographic uterine scoring system as a method for the prognosis of embryo implantation in patients submitted to ICSI. METHODS: A total of 562 patients submitted to an ICSI program were prospectively evaluated on the day of hCG administration in terms of the following ultrasonographic uterine parameters: A. Endometrial thickness (< 7.0 mm = 0; 7 a 14 mm = 3; > 14 mm = ); B. Endometrial layering (three lines = 2; absence of three lines = 0); C. Myometrial contractions in 2 min (< 3 = 0; > or = 3 = 3); D. Uterine artery Doppler flow (> 3 = 0; 2.2 a 3 = 22; > or = 2 .19 = 3); E. Endometrial power Doppler (The endometrium was divided into four equal quadrants and classified as grade I = 1; II = 2; III = 3; IV = 4, according to the visualization of the power Doppler in the quadrants). The colour Doppler signal was considered to be positive when it reached at least the basal layer of the endometrium; F. Myometrial power Doppler (absent = 0 weakly present 2; strongly present = 3); G. Myometrial echogenicity (homogeneous = 2; inhomogeneous = 0). The patients were divided into 4 groups according to total score: Group I, score < 10: Group II, score 10-14, Group III, score 15-17 and Group IV, score 18-20. RESULTS: The uterine parameters using an ultrasonographic scoring system are inversely correlated with patient age (p < 0.0001). The number of days of stimulation with FSH did not differ (p = 0.10) between groups. The number of follicles measuring >16 mm was different (p = 0.01) between groups. The number of metaphase II oocytes also did not differ significantly between groups (p = 0.45). The fertilization rate was also similar (p = 0.10) for all groups. The number of transferred embryos was different between groups (p = 0.02). The rate of embryo implantation did not differ (p = 0.60) between groups. Finally, the pregnancy rates did not differ significantly (p = 0.93) between groups. CONCLUSIONS: The ultrasonographic evaluation of uterine parameters on the day of hCG administration using a scoring system is inversely correlated with patient age. In the present study, the use of this ultrasonographic score method could not identify a population with greater uterine receptivity.

Donation of oocytes as treatment for infertility in patients with premature ovarian failure. Awarded the "Nicolau de Moraes Barros" prize for gynecology

Um total de 7 ciclos de transferência de embriöes provenientes da doaçäo de oócitos foram realizados em 5 pacientes portadoreas de insuficiência ovariana precoce. As doadoras possuíam idade inferior a 35 anos, e as receptoras, apresentavam idade média de 38,6 anos. No esquema de sincronizaçäo entre doadora e receptora usou-se um ciclo semiprogramado com pílula, seguido de estimulaçäo da doadora com citrato de clomifeno e gonadotrofina menopausal humana. As receptoras foram facilmente acopladas com as doadoras através de um modelo flexível de doses crescentes de valerianato de estradiol. O número médio de oócitos doados foi de 3.14, a taxa de clivagem embrionária média de 80,2 por cento, sendo o número médio de embriöes transferidos de 2.57. A taxa de implantaçäo embrionária foi de 22,2 por cento. As gestaçöes clínicas ocorreram em 57,1 por cento dos ciclos. Provavelmente, essa série é a primeira apresentada na literatura nacional sobre a doaçäo de oócitos no tratamento da infertilidade em pacientes com insuficiência ovariana precoce

Prevençäo da hiperestimulaçäo ovariana pelo uso de agonista de GnRH (leuprolide) como indutor da ruptura folicular / Prevention of the ovarian hyperestimulation by the using of GnRH (leuprolide) agosnist for the triggering ovulation

Um grupo de 12 pacientes com infertilidade e tratados com hMG em preparaçäo para inseminaçäo intra-uterina ou para correçäo de anovulaçäo, tiveram a ovulaçäo desencadeada pela descarga de LH endógeno, através da administraçäo de 2,5mg subcutâneo de acetato de leuprolide, por terem sido consideradas de alto risco para desenvolverem a síndrome de hiperestimulaçäo ovariana (SHO). Com a utilizaçäo do agonista do GnRh a rotura folicular ocorreu em 10 das 12 pacientes (83,33 por cento) e a SHO nos graus moderado e severo näo foi observada em nenhuma paciente apesar das altas taxas pré-ovulatórias de estradiol (µ = 2.078,17pg/ml), do grande número de folículos < 15mm (µ = 10,0) e da presença de um baixo fator de sincromia ovariano (µ = 0,40).

Regras gerais de um programa de fertilizaçäo in vitro e transfência de embriöes / General rules of an in vitro fertilization and human embryos transfer program

O sucesso de um programa de fertilizaçäo in vitro com transferência de embriöes humanos (FIV-TE) pode depender de diversas variáveis. Este trabalho descreve regras gerais (clínicas e laboratoriais) que quase sempre säo omitidas dos artigos sobre esse tema, mas que foram peças fundamentais para a obtençäo, no programa de FIV-TE do Centro de Reproduçäo Humana da Maternidade Sinhá Junqueira, de índices de gestaçöes semelhantes aos serviços internacionais.

Fator de sincronia ovariano: novo parâmetro ultra-sonográfico para avaliar a performance ovariana / Ovarian synchronizing factor: new ultrasonographic parameter to evaluate ovarian performance

Um novo parâmetro ultra-sonográfico denominado de fator de sincronia ovariano (FSO) foi avaliado em 64 pacientes inférteis submetidas aos programas de estimulaçäo ovariana para reproduçäo assistida näo invasiva. O FSO no dia da administraçäo de hCG, nas pacientes que engravidaram foi significativamente maior ao obtido naquelas que näo ficaram grávidas no ciclo avaliado (t Student = 2.08, p = 0.041). O FSO pode definir uma resposta folicular homogênea (FSO próximo do valor unitário) e facilitar a identificaçäo do momento correto do uso de hCG para a obtençäo de uma performance ovariana ideal em termos de gravidez

Fator de sincronia ovariano: novo parâmetro ultra-sonográfico no prognóstico da ruptura folicular / Ovarian synchronizing factor: new ultrasonographic parameter in prognosis of follicular rupture

Um novo parâmetro ultra-sonografico denominado fator de sincronia ovariano (FSO) foi avaliado em 43 pacientes inférteis submetidas aos programas de estimulaçäo ovariana. O FSO no dia da administraçäo de hCG foi significativamente maior (W = 10, p < 0,05) no grupo de pacientes com ruptura folicular do que naquele sem ruptura. O FSO pode definir uma resposta folicular homogênea (FSO próximo do valor unitário) e facilitar a identificaçäo do momento ideal para a administraçäo de hCG, fato fundamental para o sucesso do processo de ruptura folicular em ciclos estimulados

Influência da morfologia espermática nas taxas de clivagem de embriöes num programa de fertilizaçäo in vitro / Influence of the sperm morphology in the embryo cleavage rates in in vitro fertilization program

Um total de 102 ciclos de FIV em 83 pacientes foi analisado, com o objetivo de avaliar a influência da morfologia do espermatozóide nas taxas de clivagem de embrioes, num programa de fertilizaçao in vitro. Os ciclos estudados foram divididos em dois grupos. O grupo A com 30 por cento ou mais de espermatozóides normais (83 ciclos), e o grupo B com menos de 30 por cento de espermatozóides normais (19 ciclos). Em ambos os grupos, a avaliaçao inicial do esperma apresentava uma concentraçao ( 20 X 10(6) de espermatozóides/ml e uma motilidade progressiva - 30 por cento. A taxa de clivagem foi significativamente maior (p=0,000) no grupo A (67,63 + 30,54 por cento) do que no grupo B (36,98 + 36,61 por cento), e o número de ciclos em que nao houve formaçao de embrioes foi maior no grupo B do que no A (p=0,0002).

Seleçao da populaçao masculina fertil atraves dos testes de penetraçao espermatica no muco cervical bovino e na clara do ovo / Selection of fertile male population throug spermatic penetration on bovine cervical mucus and egg albumin

A analise do fator masculino em oitenta e dois testes de penetraçao espermatica, no muco cercical bovino (TMCB) e na clara do ovo (TCO), mostrou que o TMCB e o TCO normais identificaram, ao longo do tempo, com significativa precisao, a populaçao de casais ferteis

Critérios para definir o número de embriões a serem transferidos em fertilização in vitro / Criteria to determine the number of embryos to be transferred in in vitro fertilization

Os autores fazem revisão sobre o impacto das técnicas de reprodução assistida na incidência de gravidez múltipla, relacionando seu impacto médico-social. Baseado na experiência pessoal no Centro de Reprodução Humana "Sinhá Junqueira" e na revisão da bibliografia atual, são feitas considerações sobre o número de embriões a serem transferidos em ciclos de FIV

A ultra-sonografia endometrial como fator preditivo de gravidez num programa de fertilizaçäo in vitro / Endometrial ultrasonography as a predictor of pregnancy in an in-vitro fertilization programme

A espessura e padräo endometrial foram analisados por ultrasonografia em 100 ciclos estimulados para fertilizaçäo "in vitro" no dia da administraçäo do hormônio gonadotrófico coriônico (hCG). Em 86 ciclos empregou-se para a estimulaçäo ovariana um esquema semiprogramado com pílula + citrato de clomifene + gonadotrofina menopausal humana (hCG), e nos 14 ciclos restantes usou-se um análogo do hormônio liberador de gonadotrofinas GnRH/leupro-lide) na forma de bloqueio de longa duraçäo seguido de hMG. No dia do hCG a espessura e o padräo endometrial foram avaliados por um ultrasom Ultramark 4 (ATL) com transdutor vaginal de 5 MHz. A espessura endometrial foi significativamente inferior (p = 0.03) nos ciclos semiprogramados (8.8 ñ 2.0 mm) do que a observada no grupo com análogo do GnRH (10.2 ñ 2.0mm). A distribuiçäo dos padröes I (multicamada ou "3 linhas") e II (inteiramente homogêneo, hiperecogênico em relaçäo ao tecido miometrial) em ambos os protocolos de estimulaçäo näo foram significamente diferentes (p = 0.91). A espessura endometrial no dia do hCG no grupo com padräo I (µ1 = 8.9 ñ 2.1 mm) foi similar (p = 0.76) a observada no padräo II (µ2 = 9.0 ñ 1.9 mm). Além disso, a espessura endometrial nas pacientes que engravidaram (µg = 8.5 ñ 2.2 m) näo diferiu (p = 0.22) das näo gravidas (µng = 9.0 ñ 1.9 mm). Näo houve diferença entre a incidência de gravidez nos grupos com padräo endometrial I e II (p = 0.42). Em conclusäo, os dados deste trabalho näo evidenciaram um valor preditivo de gravidez para a análise ultrasono-gráfica da espessura e refringência endometrial no dia do uso de hCG em ciclos de FIV

Qual o número ideal de embriöes a ser transferido para o útero após fertilizaçäo in vitro? / What the number of embryos to be transferred fot the utero after in vitro fertilization

Atualmente, está bem estabelecido que a transferência de diversos embriöes após fertilizaçäo "in vitro" (FIV) leva a uma maior taxa de gravidez do que quando se transfere apenas um único embriäo. Contudo, a transferência de um número elevado de embriöes acarreta o aumento da incidência de gestaçöes múltiplas. Os objetivos deste estudo foram avaliar as repercussöes do número de embriöes transferidos sobre as taxas de gravidez e de gestaçöes múltiplas num programa de FIV. Além disso, propor um número ideal de embriöes para ser transferido ao útero discutindo-se as soluçöes alternativas para os problemas decorrentes da formaçäo de um número excessivo de embriöes. Um total de 177 ciclos de FIV realizados em 138 casais foram analisados entre janeiro de 1991 e março de 1992. A taxa de gravidez por transferência de 1(n=29), 2(n=30), 3(n=20), 4(n=41), 5(n=20) embrioes foi respectivamente de 3.4 por cento (gestaçöes : 1), 30 por cento (gestaçöes + 9), 45 por cento (gestaçöes : 9), 39 por cento (gestaçöes : 16) e 35 por cento (gestaçöes : 7). Näo houve diferença significativa na taxa de gravidez (p=0.15), quando se transferiu e ou 4 embrioes. Por outro lado, a ocorrência de gestaçöes multifetais foi a seguinte: quando foram transferidos 2 ou 3 embriöes 22.2 por cento de Gêmeos, para 4 embriöes 25 por cento de Gêmeos e 6.25 por cento de trigêmeos, sendo que com 5 embriöes obserou-se 14.28 por cento de trigêmeos. Em conclusäo, a transferência de um número maior que 3 embriöes näo acarreta a subsequente elevaçäo das taxas de gestaçöes, apenas propicia o aumento da incidência de gestaçöes multifetais. Os embriöes excedentes devem ser criopreservados para uma posterio transferência, isto até que uma adequada tecnologia para criopreservaçäo de oócitos esteja estabelecida