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1.
Hum Reprod ; 35(12): 2860-2870, 2020 12 01.
Artículo en Inglés | MEDLINE | ID: mdl-33190155

RESUMEN

STUDY QUESTION: Do IVF treatment and laboratory factors affect singleton birthweight (BW)? SUMMARY ANSWER: BWs of IVF-conceived singleton babies are increasing with time, but we cannot identify the specific treatment factors responsible. WHAT IS KNOWN ALREADY: IVF-conceived singleton babies from fresh transfers have slightly lower BW than those conceived naturally, whilst those from frozen embryo transfer (FET) cycles are heavier and comparable to naturally conceived offspring. Our recent studies have shown that BW varies significantly between different IVF centres, and in a single centre, is also increasing with time, without a corresponding change in BWs of naturally conceived infants. Although it is likely that factors in the IVF treatment cycle, such as hormonal stimulation or embryo laboratory culture conditions, are associated with BW differences, our previous study designs were not able to confirm this. STUDY DESIGN, SIZE, DURATION: Data relating to BW outcomes, IVF treatment and laboratory parameters were collated from pre-existing electronic records in five participating centres for all singleton babies conceived between August 2007 and December 2014. PARTICIPANTS/MATERIALS, SETTING, METHODS: Seven thousand, five hundred and eighty-eight births, 6207 from fresh and 1381 from FET. Infants with severe congenital abnormalities were excluded. The primary outcome of gestation-adjusted BW and secondary outcomes of unadjusted BW and gestation were analysed using multivariable regression models with robust standard errors to allow for the correlation between infants with the same mother. The models tested treatment factors allowing for confounding by centre, time and patient characteristics. A similar matched analysis of a subgroup of 379 sibling pairs was also performed. MAIN RESULTS AND THE ROLE OF CHANCE: No significant associations of birth outcomes with IVF embryo culture parameters were seen independent of clinic or time, including embryo culture medium, incubator type or oxygen level, although small differences cannot be ruled out. We did not detect any significant differences associated with hormonal stimulation in fresh cycles or hormonal synchronization in FET cycles. Gestation-adjusted BW increased by 13.4 (95% CI 0.6-26.1) g per year over the period of the study, and babies born following FET were 92 (95% CI 57-128) g heavier on average than those from the fresh transfer. LIMITATIONS, REASONS FOR CAUTION: Although no specific relationships have been identified independent of clinic and time, the confidence intervals remain large and do not exclude clinically relevant effect sizes. As this is an observational study, residual confounding may still be present. WIDER IMPLICATIONS OF THE FINDINGS: This study demonstrates the potential for large scale analysis of routine data to address critical questions concerning the long-term implications of IVF treatment, in accordance with the Developmental Origins of Health and Disease hypothesis. However, much larger studies, at a national scale with sufficiently detailed data, are required to identify the treatment parameters associated with differences in BW or other relevant outcomes. STUDY FUNDING/COMPETING INTEREST(S): This work was supported by the EU FP7 project grant, EpiHealthNet (FP7-PEOPLE-2012-ITN-317146). No competing interests were identified. TRIAL REGISTRATION NUMBER: N/A.


Asunto(s)
Fertilización In Vitro , Laboratorios , Peso al Nacer , Estudios de Cohortes , Femenino , Humanos , Embarazo , Estudios Retrospectivos
2.
Behav Res Methods ; 42(3): 671-84, 2010 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-20805589

RESUMEN

Visual perception can be influenced by top-down processes related to the observer's goals and expectations, as well as by bottom-up processes related to low-level stimulus attributes, such as luminance, contrast, and spatial frequency. When using different physical stimuli across psychological conditions, one faces the problem of disentangling the contributions of low- and high-level factors. Here, we make available the SHINE (spectrum, histogram, and intensity normalization and equalization) toolbox for MATLAB, which we have found useful for controlling a number of image properties separately or simultaneously. The toolbox features functions for specifying the (rotational average of the) Fourier amplitude spectra, for normalizing and scaling mean luminance and contrast, and for exact histogram specification optimized for perceptual visual quality. SHINE can thus be employed for parametrically modifying a number of image properties or for equating them across stimuli to minimize potential low-level confounds in studies on higher level processes.


Asunto(s)
Estimulación Luminosa/métodos , Programas Informáticos , Algoritmos , Calibración , Sensibilidad de Contraste , Análisis de Fourier , Humanos , Reconocimiento Visual de Modelos , Valores de Referencia
3.
Hum Fertil (Camb) ; 9(3): 175-80, 2006 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-17008270

RESUMEN

Ovarian hyperstimulation syndrome (OHSS) is a serious and potentially life-threatening complication following ovarian stimulation for in vitro fertilization (IVF). Coasting is the practice whereby the gonadotrophins are withheld and the administration of human chorionic gonadotrophin (hCG) is delayed until serum oestradiol (E2) has decreased to what is considered to be a safe level, to prevent the onset of OHSS. This study aimed to assess the length of coasting on the reproductive outcome in women at risk of developing OHSS. Coasting was undertaken when the serum E2 concentrations were > or = 17000 pmol/L but < 21000 pmol/L. Daily E2 measurements were performed and hCG was administered when hormone levels decreased to < 17000 pmol/L. Eighty-one women who had their stimulation cycles coasted were grouped according to the number of coasting days. Severe OHSS occurred in one case, which represented 1.2% of patients who underwent coasting because of an increased risk of developing the syndrome. No difference was found between cycles coasted for 1 - 3 days and cycles coasted for > or = 4 days in terms of oocyte maturity, fertilization and embryo cleavage rates. Women in whom coasting lasted for > or = 4 days had significantly fewer oocytes retrieved (P < 0.05) and decreased implantation rate (P < 0.05) compared to those coasted for 1 - 3 days. Pregnancy rate/embryo transfer and live birth rate did not differ between groups. In conclusion, coasting appears to decrease the risk of OHSS without compromising the IVF cycle pregnancy outcome. Prolonged coasting is, however, associated with reduced implantation rates, perhaps due to the deleterious effects on the endometrium rather than the oocytes.


Asunto(s)
Fertilización In Vitro/efectos adversos , Fertilización In Vitro/métodos , Síndrome de Hiperestimulación Ovárica/prevención & control , Gonadotropina Coriónica/administración & dosificación , Protocolos Clínicos , Estradiol/sangre , Femenino , Hormona Liberadora de Gonadotropina/agonistas , Humanos , Menotropinas/administración & dosificación , Síndrome de Hiperestimulación Ovárica/etiología , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Factores de Riesgo , Inyecciones de Esperma Intracitoplasmáticas/efectos adversos , Inyecciones de Esperma Intracitoplasmáticas/métodos , Factores de Tiempo
4.
Ann Thorac Surg ; 85(1): 310-1, 2008 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-18154831

RESUMEN

Cold agglutinins are of unique relevance in cardiac surgery because of the use of hypothermic cardiopulmonary bypass (CPB). Immunoglobulin M autoantibodies to red blood cells, which activate at varying levels of hypothermia, can cause catastrophic hemagglutination, microvascular thrombosis, or hemolysis. Management of CPB and myocardial protection requires individualized planning. We describe a case of aortic valve replacement in a patient with high titre cold agglutinins and a high thermal amplitude for antibody activation. Normothermic CPB and continuous warm blood cardioplegia were successfully used.


Asunto(s)
Estenosis de la Válvula Aórtica/cirugía , Puente Cardiopulmonar/métodos , Enfermedad Coronaria/cirugía , Paro Cardíaco Inducido/métodos , Daño por Reperfusión Miocárdica/prevención & control , Anciano , Estenosis de la Válvula Aórtica/complicaciones , Estenosis de la Válvula Aórtica/diagnóstico por imagen , Bioprótesis , Enfermedad Coronaria/complicaciones , Enfermedad Coronaria/diagnóstico por imagen , Crioglobulinas/efectos adversos , Crioglobulinas/análisis , Estudios de Seguimiento , Implantación de Prótesis de Válvulas Cardíacas/métodos , Humanos , Complicaciones Intraoperatorias/prevención & control , Masculino , Cuidados Preoperatorios/métodos , Radiografía , Medición de Riesgo , Índice de Severidad de la Enfermedad , Resultado del Tratamiento , Ultrasonografía , Isquemia Tibia/métodos
5.
Fertil Steril ; 85(5): 1464-8, 2006 May.
Artículo en Inglés | MEDLINE | ID: mdl-16580673

RESUMEN

OBJECTIVE: To compare the effect of prophylactic laparoscopic salpingectomy versus division of the fallopian tubes on ovarian response to gonadotropins in women undergoing IVF. DESIGN: Retrospective study. SETTING: National Health Service-based tertiary referral center for reproductive medicine. PATIENT(S): One hundred sixty-eight women with tubal factor infertility. Sixty-five women with hydrosalpinges had either salpingectomy (n = 40, group A) or proximal tubal division (n = 25, group B), while the remaining women with tubal disease but without hydrosalpinges acted as the control group (n = 103, group C). INTERVENTION(S): Prophylactic laparoscopic salpingectomy or proximal division of the fallopian tubes and ovarian stimulation with gonadotropins for IVF. MAIN OUTCOME MEASURE(S): Day 2 serum FSH levels before surgery and 3 months after surgery but before ovarian stimulation, ovarian response assessed as total dose of hMG administered, serum E2 concentrations on day 3 and day 8 of stimulation and on the day of hCG injection, number of follicles, and number of oocytes retrieved and fertilized. RESULT(S): In group A, baseline FSH levels were significantly raised after surgery compared with before surgery. Postsurgery FSH concentrations were significantly higher in group A compared with group B. The number of follicles (15-20 mm) was significantly lower in group A compared with group B and group C. The serum E2 levels on day 8 of stimulation were lower in group A compared with group B, and on the day of hCG injection it was significantly reduced in group A compared with groups B and C. The number of oocytes retrieved per cycle was significantly lower in group A compared with group B. There were no significant differences in pregnancy rates and miscarriage rates among the three groups. CONCLUSION(S): These findings suggest that prophylactic salpingectomy in women with hydrosalpinx may compromise ovarian response to stimulation without affecting pregnancy rates. A randomized control trial is recommended to determine the most appropriate laparoscopic procedure in the management of hydrosalpinx before IVF.


Asunto(s)
Enfermedades de las Trompas Uterinas/tratamiento farmacológico , Enfermedades de las Trompas Uterinas/cirugía , Gonadotropinas/administración & dosificación , Infertilidad Femenina/terapia , Laparoscopía/métodos , Inducción de la Ovulación/métodos , Salpingostomía/métodos , Adulto , Terapia Combinada , Enfermedades de las Trompas Uterinas/complicaciones , Femenino , Fertilización In Vitro , Humanos , Infertilidad Femenina/etiología , Ovario/efectos de los fármacos , Embarazo , Resultado del Embarazo , Estudios Retrospectivos , Resultado del Tratamiento
6.
Fertil Steril ; 85(3): 603-9, 2006 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-16500326

RESUMEN

OBJECTIVE: To assess the implantation, pregnancy, and live birth rates after the transfer of frozen-thawed embryos (FET) in a natural or hormonal control cycle. DESIGN: Retrospective study. SETTING: National Health Service tertiary referral center for reproductive medicine in Manchester, United Kingdom. PATIENT(S): Two comparable groups of women with regular menstrual cycles: Group A (n = 212) had FET in a natural cycle after spontaneous ovulation; group B (n = 205) had FET in a pituitary-desensitized hormonally controlled cycle. INTERVENTION(S): In group B, GnRH agonist was commenced in the midluteal phase of the previous cycle and discontinued 3 days before embryo transfer. Oral estradiol valerate and vaginal progesterone pessary were used to prepare the endometrium. Embryo transfer was carried out 3 days after detection of the endogenous LH surge in group A and on day 3 of progesterone administration in group B. MAIN OUTCOME MEASURE(S): Implantation, pregnancy, and live birth rates per cycle and per embryo transfer (ET). RESULT(S): In the 212 women who had natural-cycle FET, 172 ETs were performed and 247 embryos replaced. The implantation rate was 14.1% (35/247). Twenty clinical pregnancies (20/172, 11.6%) were achieved. In the 205 women who had down-regulated hormone replacement-cycle FET, 173 embryo transfers were performed and 243 embryos replaced. The implantation rate was 13.5% (33/243). Eighteen clinical pregnancies (18/173, 10.2%) were achieved. There were no significant differences between the two groups with regard to the implantation, clinical pregnancy, or live birth rates per cycle or per ET. CONCLUSION(S): These findings suggest that both FET protocols are equally effective in terms of implantation rate and pregnancy outcome in women with regular menstrual cycles.


Asunto(s)
Criopreservación , Transferencia de Embrión , Estradiol/análogos & derivados , Hormona Liberadora de Gonadotropina/agonistas , Fase Luteínica , Progesterona/administración & dosificación , Administración Intravaginal , Administración Oral , Tasa de Natalidad , Implantación del Embrión , Endometrio/efectos de los fármacos , Estradiol/administración & dosificación , Estradiol/uso terapéutico , Femenino , Humanos , Nacimiento Vivo , Hormona Luteinizante/sangre , Ciclo Menstrual , Pesarios , Embarazo , Índice de Embarazo , Progesterona/uso terapéutico , Estudios Retrospectivos , Resultado del Tratamiento
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