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1.
Hum Reprod ; 2024 May 23.
Artigo em Inglês | MEDLINE | ID: mdl-38783613

RESUMO

STUDY QUESTION: After an IVF cycle cancellation, does changing the stimulation protocol affect the odds of live birth and recurrent cancellation in the subsequent cycle? SUMMARY ANSWER: After IVF cycle cancellation, compared to those who repeated the same stimulation protocol, those who changed their protocol had higher odds of live birth and lower odds of recurrent cycle cancellation. WHAT IS KNOWN ALREADY: There is limited data addressing the effect of changing the stimulation protocol after an IVF cycle is cancelled during initial stimulation. The odds of live birth outcomes are not known so far in studies addressing the effect of changing the protocol. STUDY DESIGN, SIZE, DURATION: Retrospective Cohort Study using the 2014-2017 Society for Assisted Reproductive Technology Clinic Outcome Reporting System (SART CORS) database. PARTICIPANTS/MATERIALS, SETTING, METHODS: The data included 13 135 patients with a first autologous IVF cycle that resulted in a cycle cancellation and was followed by a second autologous cycle within the study period. We excluded fertility preservation cycles, supernumerary cycle attempts after the second IVF cycle attempt, and cycles with more than one stimulation protocol documented per cycle start. Patients who received the same protocol for both cycles (n = 6434) were compared to those who changed their protocol in the second cycle (n = 6701). Multivariable logistic regression analyses were performed to estimate the adjusted odds of live birth and recurrent cancellation. MAIN RESULTS AND THE ROLE OF CHANCE: Changing the protocol in the second cycle resulted 14% lower odds of recurrent cycle cancellation (P = 0.01) and 17% higher odds of live birth after fresh transfers (P = 0.04). When stratifying the data by specific combinations of protocol change (agonist flare, agonist suppression, antagonist), there was an increase in live birth when switching from antagonist to agonist suppression (odds ratio (OR) = 1.36, P = 0.03) and from agonist suppression to antagonist (OR = 1.73, P = 0.01) compared to those who repeated their same stimulation protocol. Specifically in poor responders, outcomes were worse when using the agonist flare protocol and significantly improved with the agonist suppression protocol. LIMITATIONS, REASONS FOR CAUTION: Comparison of response to stimulation between first and second cycles cannot be made in this study because the index IVF cycle was cancelled during ovarian stimulation, and thus there is no reportable outcome data for that cycle. Additionally, SART only tracks the three stimulation protocols addressed in this study and does not have data on more contemporary protocols that are used in poor responders thus limiting the generalizability of our findings. WIDER IMPLICATIONS OF THE FINDINGS: Using the SART CORS database, which includes >90% of all reported IVF cycles in the USA, provides generalizability to the demographically diverse IVF populations found here. In agreement with prior studies assessing change in IVF protocols, the agonist flare protocol seems to result in worse IVF outcomes, and based on our results, we believe that there is no role for the agonist flare protocol in patients with a prior poor response to stimulation. STUDY FUNDING/COMPETING INTEREST(S): None declared. TRIAL REGISTRATION NUMBER: N/A.

2.
J Clin Endocrinol Metab ; 86(8): 3918-23, 2001 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-11502833

RESUMO

GH and IGF-I secretion decrease with age. The decline in serum GH with age appears to be associated with menopause. Prior studies of GH release before and after oral and transdermal hormonal replacement in the postmenopausal patient have shown no change or an increase in GH secretion. To distinguish the somatotropic axis effects of aging from those of estrogen deficiency, we compared eight prematurely menopausal women, aged 25-40 yr, with eight postmenopausal women, aged 51-70 yr, both before and after estradiol replacement. All women had a body mass index below 28 kg/m2. All were evaluated twice with frequent blood sampling every 10 min for 24 h. Studies were performed in the absence of exogenous hormones and 6-8 wk after transdermal estradiol replacement, targeted to achieve a serum estradiol level of 367 pmol/liter. GH pulsatility was analyzed. Variables tested included mean GH levels, interpulse baseline mean, pulse frequency per 24 h, and pulse amplitude. Transdermal estrogen replacement had a significant effect on mean GH levels and mean basal GH levels in both the premature ovarian failure and the age-appropriate postmenopausal group. No differences were noted in GH pulse frequency, GH pulse amplitude, IGF-I, IGF-binding protein-1, and IGF-binding protein-3 before and after treatment. A pronounced age effect was noted between the two groups. The premature ovarian failure women secreted significantly greater mean GH than the age-appropriate postmenopausal group regardless of treatment, with a significance level of P = 0.026. Interpulse baseline GH means were greater in the premature ovarian failure women than in the age-appropriate postmenopausal group, but the significance of this relationship was obliterated after adjustment for body mass index. Pulse amplitude was significantly increased in the premature ovarian failure women compared with age-appropriate postmenopausal women (P = 0.006). No significant changes were detected in the GH pulse frequency between the premature ovarian failure and postmenopausal groups. We conclude that moderate doses of transdermal estradiol supplementation do not exert a great effect on the somatotropic axis in women. Age and body composition appear to be the predominant influences on GH activity in women.


Assuntos
Envelhecimento/fisiologia , Terapia de Reposição de Estrogênios , Hormônio do Crescimento Humano/metabolismo , Pós-Menopausa/fisiologia , Pré-Menopausa/fisiologia , Insuficiência Ovariana Primária/fisiopatologia , Adulto , Feminino , Hormônio do Crescimento Humano/sangue , Humanos , Proteína 1 de Ligação a Fator de Crescimento Semelhante à Insulina/biossíntese , Proteína 3 de Ligação a Fator de Crescimento Semelhante à Insulina/sangue , Fator de Crescimento Insulin-Like I/metabolismo , Pessoa de Meia-Idade , Insuficiência Ovariana Primária/sangue , Valores de Referência
3.
Am J Obstet Gynecol ; 178(4): 732-41, 1998 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9579435

RESUMO

OBJECTIVE: Our aim was to determine the effect of aging on the hypothalamic-pituitary-gonadal axis function. STUDY DESIGN: We studied 9 women aged 25 to 40 years with well-defined idiopathic premature ovarian failure and compared them with 8 women aged 51 to 70 years who had age-appropriate menopause. All women underwent 24 hours of frequent blood sampling every 10 minutes before and after replacement with transdermal estradiol targeted to achieve serum concentrations of approximately 100 pg/ml. RESULTS: In the absence of estrogen exposure, women with premature ovarian failure demonstrated a greater 24-hour mean luteinizing hormone concentration compared with that in the older women with age-appropriate menopause (32.3+/-4.3 mlU/ml vs 19.2+/-2.4 mlU/ml, p=0.0001). Despite the lesser luteinizing hormone serum levels in the older group, the luteinizing hormone pulse frequency per 24 hours was similar (22.1+/-3.0 pulses per 24 hours in prematurely menopausal women vs 21.9+/-2.5 pulses per 24 hours in the older postmenopausal women, p=0.94). When exposed to estrogen, mean luteinizing hormone concentrations decreased to 11.6+/-2.7 mlU/ml in prematurely menopausal women versus 4.4+/-1.0 mlU/ml in older postmenopausal women, p=0.017. Both groups had suppressed mean luteinizing hormone secretion compared with their paired, non-estradiol-exposed studies, p=0.0001. Frequency of luteinizing hormone pulsations was reduced to 16.5+/-3.5 pulses per 24 hours in prematurely menopausal women exposed to estradiol (p < 0.0058, compared with non-estradiol-exposed women). Further reduction was observed in older postmenopausal women (11.5+/-1.1 pulses per 24 hours, p=0.0001, compared with nonestradiol exposure, and p=0.0125, vs prematurely menopausal, estradiol-exposed women). Pulse amplitude was suppressed in both prematurely menopausal women (5.6+/-0.5 mlU/ml to 2.3+/-0.5 mlU/ml, p=0.0001) and older postmenopausal women (3.6+/-0.4 mlU/ml to 2.3+/-0.6 mlU/ml p=0.04) in the presence of estradiol. Although luteinizing hormone pulse amplitudes were greater in the women with premature menopause in the absence of estradiol (p=0.0028) compared with those in older postmenopausal women, pulse amplitudes became similar in the presence of estradiol. Parallel changes in mean follicle-stimulating hormone were observed. Women with premature ovarian failure had a mean follicle-stimulating hormone level of 71.1+/-9.4 mlU/ml that was suppressed to 18.0+/-4.1 mlU/ml after estradiol exposure (p=0.0001); values in older postmenopausal women were 45.9+/-6.0 and 10.3+/-2.0, respectively (p=0.0001). Although the women with premature ovarian failure secreted more follicle-stimulating hormone in the absence and presence of estradiol, only the former situation was statistically significant (p=0.0008 and p=0.23, respectively). CONCLUSIONS: These data suggest that there is an age-related decrease in gonadotropin secretion that may be hypothalamic or pituitary in origin. There is less luteinizing hormone secreted in women older than age 50. There is greater suppression of luteinizing hormone and follicle-stimulating hormone secretion by estradiol in aged women. Thus these data indicate that postmenopausal hormone changes involve central hypothalamic-pituitary alterations, as well as ovarian changes.


Assuntos
Envelhecimento/fisiologia , Hipotálamo/fisiopatologia , Menopausa/fisiologia , Hipófise/fisiopatologia , Insuficiência Ovariana Primária/fisiopatologia , Adulto , Idoso , Estradiol/sangue , Terapia de Reposição de Estrogênios , Feminino , Hormônio Foliculoestimulante/sangue , Hormônio Foliculoestimulante/metabolismo , Humanos , Hormônio Luteinizante/sangue , Hormônio Luteinizante/metabolismo , Pessoa de Meia-Idade , Periodicidade
4.
Nature ; 313(5997): 59-60, 1985.
Artigo em Inglês | MEDLINE | ID: mdl-2578217

RESUMO

It has been proposed that protein kinase C mediates cellular responses evoked by external stimuli, leading to alterations in internal free calcium concentrations. We have shown previously that histamine-secreting rat basophilic leukaemia cells (RBL-2H3), which degranulate on aggregation of the receptors for immunoglobulin IgE, contain a Ca2+- and phospholipid-dependent protein kinase (kinase C). The partially purified enzyme is activated directly by the tumour-promoting phorbol ester 12-O-tetradecanoylphorbol-13-acetate (TPA). In intact RBL cells, TPA potentiates histamine release induced by the Ca2+-ionophore A23187 (similar to the synergy reported for platelets, neutrophils and rat peritoneal mast cells). Although TPA at concentrations below 15 nM synergizes with the antigen, higher TPA concentrations inhibit secretion. This selective inhibition suggested that kinase C is involved in both the activation and termination of the secretory process. To examine this possibility, we have determined the effect of TPA on changes in free cytosolic Ca2+ concentration during antigen-induced release. We report here that TPA completely blocks the increase in Ca2+ concentration induced by antigen. Our results strongly suggest that protein kinase C is involved in the regulation of receptor-dependent Ca2+ signalling.


Assuntos
Basófilos/fisiologia , Cálcio/fisiologia , Liberação de Histamina , Forbóis/farmacologia , Proteínas Quinases/metabolismo , Acetato de Tetradecanoilforbol/farmacologia , Canais Iônicos/fisiologia , Leucemia/fisiopatologia , Proteína Quinase C , Receptores de Antígenos/fisiologia
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