RESUMEN
Natural cycle IVF, without the use of LH down-regulation, is difficult because women start spontaneous LH surges at any time of the day and on any day of the week. This is not readily compatible with delivery of a routine IVF service and so historically the natural cycle has been modified by the use of human chorionic gonadotrophin (HCG) to make the natural cycle fit convenient clinical practice. This report re-evaluates data collected some years ago and seeks to determine whether the use of HCG is ultimately beneficial. Two large series of natural cycle IVF where only LH monitoring was performed (534 cycles) or where this was combined with HCG as necessary (241 cycles) were analysed. In essence, the use of HCG introduced as many problems as it overcame: there was no net benefit with respect to the number of eggs collected or clinical pregnancies generated. In fact there was an overall deterioration in all indices. The principle difficulties with natural cycle IVF are those associated with the prediction of follicle maturity and hence timing egg collection, and the conflict between costly and intrusively frequent monitoring with simpler but far less effective approaches.
Asunto(s)
Citas y Horarios , Gonadotropina Coriónica/administración & dosificación , Fertilización In Vitro/métodos , Infertilidad Femenina/tratamiento farmacológico , Ciclo Menstrual/efectos de los fármacos , Adulto , Inhibidores de la Ciclooxigenasa/farmacología , Transferencia de Embrión , Femenino , Humanos , Indometacina/farmacología , Persona de Mediana Edad , Ovulación/efectos de los fármacos , Embarazo , Índice de Embarazo , Estudios Retrospectivos , Factores de TiempoRESUMEN
A retrospective report of pregnancy and birth rates achieved in 1010 cycles of stimulated intrauterine insemination (SIUI). Over the years there has been an increasing emphasis on safety, particularly towards reducing the number of high order multiple pregnancies. SIUI is a complex form of assisted conception and requires a high level of clinical judgement to maintain an optimal balance between maximising pregnancy and birth rates and minimising complications, of which the most serious is multiple pregnancy. Extrapolating from these results, it is concluded that a well managed SIUI programme that selects patients appropriately, monitors them intensively and has in place effective strategies to manage over-responders safely, should be able to deliver at least a 15% live birth rate per cycle started with only a 5% cycle cancellation rate. Although SIUI birth rates are lower than IVF rates, the much lower cost of SIUI means that this treatment can be more cost-effective than IVF. However SIUI remains more risky than IVF and, despite careful management, high order multiple pregnancy rates will occasionally occur. It is estimated that the rate of unavoidable high order multiple pregnancies (triplets and above) is 4 per 1000 cycles started.