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1.
Lancet ; 401(10386): 1438-1446, 2023 04 29.
Artigo em Inglês | MEDLINE | ID: mdl-37004670

RESUMO

BACKGROUND: Time-lapse monitoring is increasingly used in fertility laboratories to culture and select embryos for transfer. This method is offered to couples with the promise of improving pregnancy chances, even though there is currently insufficient evidence for superior clinical results. We aimed to evaluate whether a potential improvement by time-lapse monitoring is caused by the time-lapse-based embryo selection method itself or the uninterrupted culture environment that is part of the system. METHODS: In this three-armed, multicentre, double-blind, randomised controlled trial, couples undergoing in-vitro fertilisation or intracytoplasmic sperm injection were recruited from 15 fertility clinics in the Netherlands and randomly assigned using a web-based, computerised randomisation service to one of three groups. Couples and physicians were masked to treatment group, but embryologists and laboratory technicians could not be. The time-lapse early embryo viability assessment (EEVA; TLE) group received embryo selection based on the EEVA time-lapse selection method and uninterrupted culture. The time-lapse routine (TLR) group received routine embryo selection and uninterrupted culture. The control group received routine embryo selection and interrupted culture. The co-primary endpoints were the cumulative ongoing pregnancy rate within 12 months in all women and the ongoing pregnancy rate after fresh single embryo transfer in a good prognosis population. Analysis was by intention to treat. This trial is registered on the ICTRP Search Portal, NTR5423, and is closed to new participants. FINDINGS: 1731 couples were randomly assigned between June 15, 2017, and March 31, 2020 (577 to the TLE group, 579 to the TLR group, and 575 to the control group). The 12-month cumulative ongoing pregnancy rate did not differ significantly between the three groups: 50·8% (293 of 577) in the TLE group, 50·9% (295 of 579) in the TLR group, and 49·4% (284 of 575) in the control group (p=0·85). The ongoing pregnancy rates after fresh single embryo transfer in a good prognosis population were 38·2% (125 of 327) in the TLE group, 36·8% (119 of 323) in the TLR group, and 37·8% (123 of 325) in the control group (p=0·90). Ten serious adverse events were reported (five TLE, four TLR, and one in the control group), which were not related to study procedures. INTERPRETATION: Neither time-lapse-based embryo selection using the EEVA test nor uninterrupted culture conditions in a time-lapse incubator improved clinical outcomes compared with routine methods. Widespread application of time-lapse monitoring for fertility treatments with the promise of improved results should be questioned. FUNDING: Health Care Efficiency Research programme from Netherlands Organisation for Health Research and Development and Merck.


Assuntos
Fertilização in vitro , Sêmen , Gravidez , Masculino , Feminino , Humanos , Imagem com Lapso de Tempo/métodos , Taxa de Gravidez , Técnicas de Reprodução Assistida
2.
Hum Reprod ; 36(6): 1640-1665, 2021 05 17.
Artigo em Inglês | MEDLINE | ID: mdl-33860303

RESUMO

STUDY QUESTION: Do parental characteristics and treatment with ART affect perinatal outcomes in singleton pregnancies? SUMMARY ANSWER: Both parental and ART treatment characteristics affect perinatal outcomes in singleton pregnancies. WHAT IS KNOWN ALREADY: Previous studies have shown that singleton pregnancies resulting from ART are at risk of preterm birth. ART children are lighter at birth after correction for duration of gestation and at increased risk of congenital abnormalities compared to naturally conceived children. This association is confounded by parental characteristics that are also known to affect perinatal outcomes. It is unclear to which extent parental and ART treatment characteristics independently affect perinatal outcomes. STUDY DESIGN, SIZE, DURATION: All IVF clinics in the Netherlands (n = 13) were requested to provide data on all ART treatment cycles (IVF, ICSI and frozen-thawed embryo transfers (FET)), performed between 1 January 2000, and 1 January 2011, which resulted in a pregnancy. Using probabilistic data-linkage, these data (n = 36 683) were linked to the Dutch Perinatal Registry (Perined), which includes all children born in the Netherlands in the same time period (n = 2 548 977). PARTICIPANTS/MATERIALS, SETTING, METHODS: Analyses were limited to singleton pregnancies that resulted from IVF, ICSI or FET cycles. Multivariable models for linear and logistic regression were fitted including parental characteristics as well as ART treatment characteristics. Analyses were performed separately for fresh cycles and for fresh and FET cycles combined. We assessed the impact on the following perinatal outcomes: birth weight, preterm birth below 37 or 32 weeks of gestation, congenital malformations and perinatal mortality. MAIN RESULTS AND THE ROLE OF CHANCE: The perinatal outcomes of 31 184 out of the 36 683 ART treatment cycles leading to a pregnancy were retrieved through linkage with the Perined (85% linkage). Of those, 23 671 concerned singleton pregnancies resulting from IVF, ICSI or FET. Birth weight was independently associated with both parental and ART treatment characteristics. Characteristics associated with lower birth weight included maternal hypertensive disease, non-Dutch maternal ethnicity, nulliparity, increasing duration of subfertility, hCG for luteal phase support (compared to progesterone), shorter embryo culture duration, increasing number of oocytes retrieved and fresh embryo transfer. The parental characteristic with the greatest effect size on birth weight was maternal diabetes (adjusted difference 283 g, 95% CI 228-338). FET was the ART treatment characteristic with the greatest effect size on birth weight (adjusted difference 100 g, 95% CI 84-117) compared to fresh embryo transfer. Preterm birth was more common among mothers of South-Asian ethnicity. Preterm birth was less common among multiparous women and women with 'male factor' as treatment indication (compared to 'tubal factor'). LIMITATIONS, REASONS FOR CAUTION: Due to the retrospective nature of our study, we cannot prove causality. Further limitations of our study were the inability to adjust for mothers giving birth more than once in our dataset, missing values for several variables and limited information on parental lifestyle and general health. WIDER IMPLICATIONS OF THE FINDINGS: Multiple parental and ART treatment characteristics affect perinatal outcomes, with birth weight being influenced by the widest range of factors. This highlights the importance of assessing both parental and ART treatment characteristics in studies that focus on the health of ART-offspring, with the purpose of modifying these factors where possible. Our results further support the hypothesis that the embryo is sensitive to its early environment. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by Foreest Medical School, Alkmaar, the Netherlands (grants: FIO 1307 and FIO 1505). B.W.M. reports grants from NHMRC and consultancy for ObsEva, Merck KGaA, iGenomics and Guerbet. F.B. reports research support grants from Merck Serono and personal fees from Merck Serono. A.C. reports travel support from Ferring BV. and Theramex BV. and personal fees from UpToDate (Hyperthecosis), all outside the remit of the current work. The remaining authors report no conflict of interests. TRIAL REGISTRATION NUMBER: N/A.


Assuntos
Nascimento Prematuro , Criança , Transferência Embrionária , Feminino , Humanos , Recém-Nascido , Masculino , Países Baixos/epidemiologia , Pais , Gravidez , Nascimento Prematuro/epidemiologia , Estudos Retrospectivos
3.
Hum Reprod ; 32(5): 1028-1032, 2017 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-28333222

RESUMO

STUDY QUESTION: Are there treatment selection markers that could aid in identifying couples, with unexplained or mild male subfertility, who would have better chances of a healthy child with IVF with single embryo transfer (IVF-SET) than with IUI with ovarian stimulation (IUI-OS)? SUMMARY ANSWER: We did not find any treatment selection markers that were associated with better chances of a healthy child with IVF-SET instead of IUI-OS in couples with unexplained or mild male subfertility. WHAT IS KNOWN ALREADY: A recent trial, comparing IVF-SET to IUI-OS, found no evidence of a difference between live birth rates and multiple pregnancy rates. It was suggested that IUI-OS should remain the first-line treatment instead of IVF-SET in couples with unexplained or mild male subfertility and female age between 18 and 38 years. The question remains whether there are some couples that may have higher pregnancy chances if treated with IVF-SET instead of IUI. STUDY DESIGN, SIZE, DURATION: We performed our analyses on data from the INeS trial, where couples with unexplained or mild male subfertility and an unfavourable prognosis for natural conception were randomly allocated to IVF-SET, IVF in a modified natural cycle or IUI-OS. In view of the aim of this study, we only used data of the comparison between IVF-SET (201 couples) and IUI-OS (207 couples). PARTICIPANTS/MATERIALS, SETTING, METHODS: We pre-defined the following baseline characteristics as potential treatment selection markers: female age, ethnicity, smoking status, type of subfertility (primary/secondary), duration of subfertility, BMI, pre-wash total motile count and Hunault prediction score. For each potential treatment selection marker, we explored the association with the chances of a healthy child after IVF-SET and IUI-OS and tested if there was an interaction with treatment. Given the exploratory nature of our analysis, we used a P-value of 0.1. MAIN RESULTS AND THE ROLE OF CHANCE: None of the markers were associated with higher chances of a healthy child from IVF-SET compared to IUI-OS (P-value for interaction >0.10). LIMITATIONS, REASONS FOR CAUTION: Since this is the first large study that looked at potential treatment selection markers for IVF-SET compared to IUI-OS, we had no data on which to base a power calculation. The sample size was limited, making it difficult to detect any smaller associations. WIDER IMPLICATIONS OF THE FINDINGS: We could not identify couples with unexplained or mild male subfertility who would have had higher chances of a healthy child from immediate IVF-SET than from IUI-OS. As in the original trial IUI-OS had similar effectiveness and was less costly compared to IVF-SET, IUI-OS should remain the preferred first-line treatment in these couples. STUDY FUNDING/COMPETING INTEREST(S): The study was supported by a grant from the Netherlands Organization for Health Research and Development, and a grant from the Netherlands' association of health care insurers. There are no conflicts of interest. TRIAL REGISTRATION NUMBER: The trial was registered at the Dutch trial registry (NTR939).


Assuntos
Fertilização in vitro/métodos , Infertilidade Masculina/terapia , Inseminação Artificial/métodos , Seleção de Pacientes , Adulto , Coeficiente de Natalidade , Feminino , Fertilização , Humanos , Masculino , Gravidez , Taxa de Gravidez , Prognóstico
4.
Hum Reprod ; 31(7): 1483-92, 2016 07.
Artigo em Inglês | MEDLINE | ID: mdl-27179265

RESUMO

STUDY QUESTION: Are live birth rates (LBRs) after artificial cycle frozen-thawed embryo transfer (AC-FET) non-inferior to LBRs after modified natural cycle frozen-thawed embryo transfer (mNC-FET)? SUMMARY ANSWER: AC-FET is non-inferior to mNC-FET with regard to LBRs, clinical and ongoing pregnancy rates (OPRs) but AC-FET does result in higher cancellation rates. WHAT IS ALREADY KNOWN: Pooling prior retrospective studies of AC-FET and mNC-FET results in comparable pregnancy and LBRs. However, these results have not yet been confirmed by a prospective randomized trial. STUDY DESIGN, SIZE AND DURATION: In this non-inferiority prospective randomized controlled trial (acronym 'ANTARCTICA' trial), conducted from February 2009 to April 2014, 1032 patients were included of which 959 were available for analysis. The primary outcome of the study was live birth. Secondary outcomes were clinical and ongoing pregnancy, cycle cancellation and endometrium thickness. A cost-efficiency analysis was performed. PARTICIPANT/MATERIALS, SETTING, METHODS: This study was conducted in both secondary and tertiary fertility centres in the Netherlands. Patients included in this study had to be 18-40 years old, had to have a regular menstruation cycle between 26 and 35 days and frozen-thawed embryos to be transferred had to derive from one of the first three IVF or IVF-ICSI treatment cycles. Patients with a uterine anomaly, a contraindication for one of the prescribed medications in this study or patients undergoing a donor gamete procedure were excluded from participation. Patients were randomized based on a 1:1 allocation to either one cycle of mNC-FET or AC-FET. All embryos were cryopreserved using a slow-freeze technique. MAIN RESULTS AND THE ROLE OF CHANCE: LBR after mNC-FET was 11.5% (57/495) versus 8.8% in AC-FET (41/464) resulting in an absolute difference in LBR of -0.027 in favour of mNC-FET (95% confidence interval (CI) -0.065-0.012; P = 0.171). Clinical pregnancy occurred in 94/495 (19.0%) patients in mNC-FET versus 75/464 (16.0%) patients in AC-FET (odds ratio (OR) 0.8, 95% CI 0.6-1.1, P = 0.25). 57/495 (11.5%) mNC-FET resulted in ongoing pregnancy versus 45/464 (9.6%) AC-FET (OR 0.7, 95% CI 0.5-1.1, P = 0.15). χ(2) test confirmed the lack of superiority. Significantly more cycles were cancelled in AC-FET (124/464 versus 101/495, OR 1.4, 95% CI 1.1-1.9, P = 0.02). The costs of each of the endometrial preparation methods were comparable (€617.50 per cycle in NC-FET versus €625.73 per cycle in AC-FET, P = 0.54). LIMITATIONS, REASONS FOR CAUTION: The minimum of 1150 patients required for adequate statistical power was not achieved. Moreover, LBRs were lower than anticipated in the sample size calculation. WIDER IMPLICATIONS OF THE FINDINGS: LBRs after AC-FET were not inferior to those achieved by mNC-FET. No significant differences in clinical and OPR were observed. The costs of both treatment approaches were comparable. STUDY FUNDING/COMPETING INTERESTS: An educational grant was received during the conduct of this study. Merck Sharpe Dohme had no influence on the design, execution and analyses of this study. E.R.G. received an education grant by Merck Sharpe Dohme (MSD) during the conduct of the present study. B.J.C. reports grants from MSD during the conduct of the study. A.H. reports grants from MSD and Ferring BV the Netherlands and personal fees from MSD. Grants from ZonMW, the Dutch Organization for Health Research and Development. J.S.E.L. reports grants from Ferring, MSD, Organon, Merck Serono and Schering-Plough during the conduct of the study. F.J.M.B. receives monetary compensation as member of the external advisory board for Merck Serono, consultancy work for Gedeon Richter, educational activities for Ferring BV, research cooperation with Ansh Labs and a strategic cooperation with Roche on automated anti Mullerian hormone assay development. N.S.M. reports receiving monetary compensations for external advisory and speaking work for Ferring BV, MSD, Anecova and Merck Serono during the conduct of the study. All reported competing interests are outside the submitted work. No other relationships or activities that could appear to have influenced the submitted work. TRIAL REGISTRATION NUMBER: Netherlands trial register, number NTR 1586. TRIAL REGISTRATION DATE: 13 January 2009. FIRST PATIENT INCLUDED: 20 April 2009.


Assuntos
Transferência Embrionária/métodos , Adulto , Análise Custo-Benefício , Criopreservação , Transferência Embrionária/economia , Feminino , Humanos , Nascido Vivo , Ciclo Menstrual , Gravidez , Taxa de Gravidez
5.
Hum Reprod ; 30(10): 2331-9, 2015 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-26269539

RESUMO

STUDY QUESTION: What is the cost-effectiveness of in vitro fertilization (IVF) with conventional ovarian stimulation, single embryo transfer (SET) and subsequent cryocycles or IVF in a modified natural cycle (MNC) compared with intrauterine insemination with controlled ovarian hyperstimulation (IUI-COH) as a first-line treatment in couples with unexplained subfertility and an unfavourable prognosis on natural conception?. SUMMARY ANSWER: Both IVF strategies are significantly more expensive when compared with IUI-COH, without being significantly more effective. In the comparison between IVF-MNC and IUI-COH, the latter is the dominant strategy. Whether IVF-SET is cost-effective depends on society's willingness to pay for an additional healthy child. WHAT IS KNOWN ALREADY: IUI-COH and IVF, either after conventional ovarian stimulation or in a MNC, are used as first-line treatments for couples with unexplained or mild male subfertility. As IUI-COH is less invasive, this treatment is usually offered before proceeding to IVF. Yet, as conventional IVF with SET may lead to higher pregnancy rates in fewer cycles for a lower multiple pregnancy rate, some have argued to start with IVF instead of IUI-COH. In addition, IVF in the MNC is considered to be a more patient friendly and less costly form of IVF. STUDY DESIGN, SIZE, DURATION: We performed a cost-effectiveness analysis alongside a randomized noninferiority trial. Between January 2009 and February 2012, 602 couples with unexplained infertility and a poor prognosis on natural conception were allocated to three cycles of IVF-SET including frozen embryo transfers, six cycles of IVF-MNC or six cycles of IUI-COH. These couples were followed until 12 months after randomization. PARTICIPANTS/MATERIALS, SETTING, METHODS: We collected data on resource use related to treatment, medication and pregnancy from the case report forms. We calculated unit costs from various sources. For each of the three strategies, we calculated the mean costs and effectiveness. Incremental cost-effectiveness ratios (ICER) were calculated for IVF-SET compared with IUI-COH and for IVF-MNC compared with IUI-COH. Nonparametric bootstrap resampling was used to investigate the effect of uncertainty in our estimates. MAIN RESULTS AND THE ROLE OF CHANCE: There were 104 healthy children (52%) born in the IVF-SET group, 83 (43%) the IVF-MNC group and 97 (47%) in the IUI-COH group. The mean costs per couple were €7187 for IVF-SET, €8206 for IVF-MNC and €5070 for IUI-COH. Compared with IUI-COH, the costs for IVF-SET and IVF-MNC were significantly higher (mean differences €2117; 95% CI: €1544-€2657 and €3136, 95% CI: €2519-€3754, respectively).The ICER for IVF-SET compared with IUI-COH was €43 375 for the birth of an additional healthy child. In the comparison of IVF-MNC to IUI-COH, the latter was the dominant strategy, i.e. more effective at lower costs. LIMITATIONS, REASONS FOR CAUTION: We only report on direct health care costs. The present analysis is limited to 12 months. WIDER IMPLICATIONS OF THE FINDINGS: Since we found no evidence in support of offering IVF as a first-line strategy in couples with unexplained and mild subfertility, IUI-COH should remain the treatment of first choice. STUDY FUNDING/COMPETING INTERESTS: The study was supported by a grant from ZonMw, the Netherlands Organization for Health Research and Development, (120620027) and a grant from Zorgverzekeraars Nederland, the Netherlands' association of health care insurers (09-003). TRIAL REGISTRATION NUMBER: Current Controlled Trials ISRCTN52843371; Nederlands Trial Register NTR939.


Assuntos
Transferência Embrionária/economia , Fertilização in vitro/economia , Fertilização in vitro/métodos , Inseminação Artificial/economia , Indução da Ovulação/economia , Transferência de Embrião Único/economia , Adulto , Análise Custo-Benefício , Criopreservação , Transferência Embrionária/métodos , Feminino , Fertilização , Humanos , Infertilidade Masculina/terapia , Inseminação Artificial/métodos , Masculino , Modelos Econômicos , Países Baixos , Indução da Ovulação/métodos , Gravidez , Resultado da Gravidez , Taxa de Gravidez , Prognóstico , Transferência de Embrião Único/métodos
6.
BMJ ; 350: g7771, 2015 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-25576320

RESUMO

OBJECTIVES: To compare the effectiveness of in vitro fertilisation with single embryo transfer or in vitro fertilisation in a modified natural cycle with that of intrauterine insemination with controlled ovarian hyperstimulation in terms of a healthy child. DESIGN: Multicentre, open label, three arm, parallel group, randomised controlled non-inferiority trial. SETTING: 17 centres in the Netherlands. PARTICIPANTS: Couples seeking fertility treatment after at least 12 months of unprotected intercourse, with the female partner aged between 18 and 38 years, an unfavourable prognosis for natural conception, and a diagnosis of unexplained or mild male subfertility. INTERVENTIONS: Three cycles of in vitro fertilisation with single embryo transfer (plus subsequent cryocycles), six cycles of in vitro fertilisation in a modified natural cycle, or six cycles of intrauterine insemination with ovarian hyperstimulation within 12 months after randomisation. MAIN OUTCOME MEASURES: The primary outcome was birth of a healthy child resulting from a singleton pregnancy conceived within 12 months after randomisation. Secondary outcomes were live birth, clinical pregnancy, ongoing pregnancy, multiple pregnancy, time to pregnancy, complications of pregnancy, and neonatal morbidity and mortality RESULTS: 602 couples were randomly assigned between January 2009 and February 2012; 201 were allocated to in vitro fertilisation with single embryo transfer, 194 to in vitro fertilisation in a modified natural cycle, and 207 to intrauterine insemination with controlled ovarian hyperstimulation. Birth of a healthy child occurred in 104 (52%) couples in the in vitro fertilisation with single embryo transfer group, 83 (43%) in the in vitro fertilisation in a modified natural cycle group, and 97 (47%) in the intrauterine insemination with controlled ovarian hyperstimulation group. This corresponds to a risk, relative to intrauterine insemination with ovarian hyperstimulation, of 1.10 (95% confidence interval 0.91 to 1.34) for in vitro fertilisation with single embryo transfer and 0.91 (0.73 to 1.14) for in vitro fertilisation in a modified natural cycle. These 95% confidence intervals do not extend below the predefined threshold of 0.69 for inferiority. Multiple pregnancy rates per ongoing pregnancy were 6% (7/121) after in vitro fertilisation with single embryo transfer, 5% (5/102) after in vitro fertilisation in a modified natural cycle, and 7% (8/119) after intrauterine insemination with ovarian hyperstimulation (one sided P=0.52 for in vitro fertilisation with single embryo transfer compared with intrauterine insemination with ovarian hyperstimulation; one sided P=0.33 for in vitro fertilisation in a modified natural cycle compared with intrauterine insemination with controlled ovarian hyperstimulation). CONCLUSIONS: In vitro fertilisation with single embryo transfer and in vitro fertilisation in a modified natural cycle were non-inferior to intrauterine insemination with controlled ovarian hyperstimulation in terms of the birth of a healthy child and showed comparable, low multiple pregnancy rates.Trial registration Current Controlled Trials ISRCTN52843371; Nederlands Trial Register NTR939.


Assuntos
Transferência Embrionária/métodos , Fertilização in vitro/métodos , Infertilidade Masculina , Inseminação Artificial/métodos , Gravidez Múltipla/estatística & dados numéricos , Transferência de Embrião Único , Adolescente , Adulto , Feminino , Seguimentos , Humanos , Masculino , Países Baixos , Gravidez , Resultado da Gravidez , Adulto Jovem
7.
J Endocrinol ; 124(3): 425-32, 1990 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-2159045

RESUMO

Treatment of female rats for 3 weeks with the antigestagen 11 beta-(4-dimethylaminophenyl)-17 beta-hydroxy-17 alpha-(prop-1-ynyl)-estra- 4,9-dien-3-one (mifepristone) results in pituitary and ovarian enlargement. The present study dealt with the possible mechanism(s) of these responses. Ovarian enlargement appeared to be dependent upon prolactin. In the absence of prolactin, during combined treatment with mifepristone and the dopamine agonist 2-Br-alpha-ergokryptine, ovarian growth was significantly suppressed. It was unclear why persistent hyperprolactinaemia, due to treatment with mifepristone, resulted in persistence of functionally active corpora lutea despite intermittent ovulation, while persistent hyperprolactinaemia due to ectopic pituitary grafts did not. Pituitary enlargement appeared to be dependent upon the persistence of ovarian oestrogen secretion during the treatment period. Ovariectomy or lactation fully inhibited this response. Pituitary enlargement and prolactin secretion in ovariectomized rats in response to exogenous oestrogen (injections of oestradiol benzoate) were significantly enhanced by additional treatment with mifepristone. It is concluded that mifepristone facilitates the effect of oestrogen on pituitary lactotrophs, thereby enhancing pituitary growth. Ovarian enlargement during treatment with mifepristone may be specific for rats due to the luteotrophic action of prolactin in these animals. Pituitary enlargement due to facilitation of oestrogen-induced pituitary growth may become a focus of attention when this or similar antigestagenic drugs are being used for prolonged periods in clinical trials, e.g. for limiting steroid-sensitive tumour growth.


Assuntos
Sistema Hipotálamo-Hipofisário/efeitos dos fármacos , Mifepristona/farmacologia , Ovário/efeitos dos fármacos , 20-alfa-Di-Hidroprogesterona/sangue , Glândulas Suprarrenais/efeitos dos fármacos , Hormônio Adrenocorticotrópico/sangue , Animais , Peso Corporal/efeitos dos fármacos , Bromocriptina/farmacologia , Preparações de Ação Retardada , Feminino , Gonanos/farmacologia , Tamanho do Órgão/efeitos dos fármacos , Hipófise/efeitos dos fármacos , Progesterona/sangue , Prolactina/sangue , Ratos , Útero/efeitos dos fármacos
8.
Br J Nutr ; 66(1): 17-26, 1991 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-1931902

RESUMO

Treatment of lactating rats with the anti-progestin Mifepristone or Onapristone adversely affects growth of their litters. The present studies aimed to elucidate the underlying mechanism. The treatment did not interfere with the behavioural interactions between mothers and pups, which are required for normal litter growth. Treatment with the antagonists had a stimulatory action on ovarian oestrogen production. However, ovarian hormones did not play a role in litter growth impairment, as this also occurred with lactating ovariectomized rats. Treatment with anti-progestins did not affect the concentrations of the macronutrients in milk (protein, lactose and lipid), nor did it change the fatty acid composition of lipid. Reduced litter growth was not related to a possible direct effect of exposure of the suckling young to the drugs via the milk. Direct injections into them unequivocally affected adrenal gland and testicular development, but did not affect their body-weight development. Milk secretion, as measured by the milk weight accumulating during 6 or 24 h following sudden removal of litters in advanced lactation, was not impaired by the treatments. However, the ingestion of food and water by dams treated with Mifepristone was significantly below that of control animals. It is concluded that litter growth impairment during treatment of lactating rats with anti-progestin results from the reduction of the intake of food and water by the mother.


Assuntos
Animais Recém-Nascidos/crescimento & desenvolvimento , Ingestão de Líquidos/efeitos dos fármacos , Ingestão de Alimentos/efeitos dos fármacos , Progesterona/antagonistas & inibidores , Animais , Peso Corporal/efeitos dos fármacos , Feminino , Gonanos/farmacologia , Lactação/efeitos dos fármacos , Masculino , Mifepristona/farmacologia , Leite/análise , Ovariectomia , Gravidez , Ratos , Ratos Endogâmicos
9.
J Reprod Fertil ; 87(2): 593-601, 1989 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-2513392

RESUMO

The progesterone antagonists, mifepristone (RU-38,486) and onapristone (ZK-98,299), given as 2 mg daily, did not markedly affect lactation in rats. Both litter growth and time spent by 10-pup litters attached to their mothers were similar in antagonist-treated mothers and in solvent-treated controls. The progesterone antagonists did not affect the steroid content in corpora lutea remaining from the preceding pregnancy. Corpora lutea formed after post-partum ovulation also showed nearly normal function throughout the first 17 days of lactation. It is concluded that progesterone itself plays no role in the initiation or maintenance of luteal function when prolactin secretion is governed through an action independent of the ovaries, as through suckling. Antagonist-treated rats ovulated around Day 13 of lactation despite suckling. This ovulation was not associated with a decrease of progesterone production by the corpora lutea formed after post-partum ovulation. Apparently, elimination of progesterone action may protect corpora lutea from luteolysis. The latter finding indicates a possible role of progesterone in luteolysis and deserves further analysis.


Assuntos
Corpo Lúteo/fisiologia , Gonanos/farmacologia , Lactação/efeitos dos fármacos , Mifepristona/farmacologia , Progesterona/antagonistas & inibidores , Algestona/sangue , Animais , Corpo Lúteo/efeitos dos fármacos , Feminino , Lactação/sangue , Luteólise , Ovulação , Gravidez , Progesterona/biossíntese , Progesterona/sangue , Prolactina/sangue , Ratos , Ratos Endogâmicos
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