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1.
Hum Reprod ; 35(9): 1954-1963, 2020 09 01.
Article de Anglais | MEDLINE | ID: mdl-31838515

RÉSUMÉ

In IVF/ICSI treatment, the FSH starting dose is often increased in predicted low responders from the belief that it improves the chance of having a baby by maximizing the number of retrieved oocytes. This intervention has been evaluated in several randomized controlled trials, and despite a slight increase in the number of oocytes-on average one to two more oocytes in the high versus standard dose group-no beneficial impact on the probability of a live birth has been demonstrated (risk difference, -0.02; 95% CI, -0.11 to 0.06). Still, many clinicians and researchers maintain a highly ingrained belief in 'the more oocytes, the better'. This is mainly based on cross-sectional studies, where the positive correlation between the number of retrieved oocytes and the probability of a live birth is interpreted as a direct causal relation. If the latter would be present, indeed, maximizing the oocyte number would benefit our patients. The current paper argues that the use of high FSH doses may not actually improve the probability of a live birth for predicted low responders undergoing IVF/ICSI treatment and exemplifies the flaws of directly using cross-sectional data to guide FSH dosing in clinical practice. Also, difficulties in the de-implementation of the increased FSH dosing strategy are discussed, which include the prioritization of intermediate outcomes (such as cycle cancellations) and the potential biases in the interpretation of study findings (such as confirmation or rescue bias).


Sujet(s)
Fécondation in vitro , Injections intracytoplasmiques de spermatozoïdes , Études transversales , Femelle , Hormone folliculostimulante , Humains , Naissance vivante , Induction d'ovulation , Grossesse , Taux de grossesse
2.
Hum Reprod ; 32(7): 1457-1464, 2017 07 01.
Article de Anglais | MEDLINE | ID: mdl-28505246

RÉSUMÉ

STUDY QUESTION: Does long-term exogenous testosterone administration result in polycystic ovarian morphology (PCOM), determined by (3D) transvaginal ultrasound (TVU) in female-to-male transsexuals (FtMs). SUMMARY ANSWER: Long-term exogenous testosterone administration in FtMs does not result in PCOM determined by (3D) TVU. WHAT IS KNOWN ALREADY: The role of androgens in the pathophysiology of polycystic ovary syndrome (PCOS) is still unclear. From animal studies, intra-ovarian androgens have been suggested to disturb folliculogenesis, through a pro-atretic effect on growing follicles. It remains debatable whether exogenous androgens induce PCOM in humans. In the past histomorphologic studies indicated that androgen administration in FtMs could cause PCO-like changes. However, ultrasound morphology is an established criterion for PCOS, TVU data of ovaries after prolonged androgen exposure are lacking. STUDY DESIGN, SIZE, DURATION: Prospective, observational, case-control study, in an academic setting, performed in 2014-2015, including 56 FtMs and 80 controls. PARTICIPANTS/MATERIALS, SETTING, METHODS: The study population consisted of adult FtMs treated with long-term testosterone, as part of their cross-sex hormone treatment, and scheduled for sex-reassignment surgery (bilateral salpingo-oophorectomy). Prior to the operation, under anaesthetics TVU measurements (3D transvaginal probe 3-9 MHz; HD11, Philips Ultrasound, Inc.) of the ovaries were performed. The control group consisted of females from a general population who underwent the same TVU and analysis. Antral follicle count (AFC) (3D) and ovarian volume (3D) were calculated using specialized software. PCOM was defined as AFC of 12 or more follicles (2-10 mm) in at least one ovary. MAIN RESULTS AND THE ROLE OF CHANCE: Prevalence rates of PCOM were not significantly different in the FtMs compared to controls, determined by (3D) TVU: 32.1% (17/53) versus 30.7% (23/75), P = 0.87. LIMITATIONS, REASONS FOR CAUTION: Testosterone levels in FtMs are supraphysiological, and may not be comparable to the testosterone levels in women with PCOS. However, we applied a unique and ethically acceptable opportunity of exploring the effects of androgens on human ovaries. WIDER IMPLICATIONS OF THE FINDINGS: This first explorative study shows that long-term exogenous testosterone administration in adult women does not seem to induce PCOM determined by TVU. STUDY FUNDING/COMPETING INTEREST(S): None. TRIAL REGISTRATION NUMBER: The trial was registered at the Dutch Trial Register (www.trialregister.nl), registration number NTR4784.


Sujet(s)
Androgènes/effets indésirables , Hyperandrogénie/induit chimiquement , Ovaire/effets des médicaments et des substances chimiques , Syndrome des ovaires polykystiques/induit chimiquement , Testostérone/effets indésirables , Transsexualisme/traitement médicamenteux , Centres hospitaliers universitaires , Administration par voie cutanée , Adulte , Androgènes/administration et posologie , Androgènes/usage thérapeutique , Études cas-témoins , Femelle , Gels , Humains , Hyperandrogénie/imagerie diagnostique , Imagerie tridimensionnelle , Injections musculaires , Mâle , Pays-Bas/épidémiologie , Ovaire/imagerie diagnostique , Syndrome des ovaires polykystiques/imagerie diagnostique , Syndrome des ovaires polykystiques/épidémiologie , Prévalence , Études prospectives , Testostérone/administration et posologie , Testostérone/analogues et dérivés , Testostérone/usage thérapeutique , Facteurs temps , Échographie
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