To examine the cumulative conception rate and live birth rate in women undergoing IVF and to assess the influence of prognostic factors on cumulative conception rate and discontinuation of treatment. Retrospective analysis of data from couples undergoing IVF. Assisted conception unit of a university hospital. PATIENT(S): Two thousand fifty-six patients undergoing 2708 cycles of IVF from April 1992 to March 1999. MAIN OUTCOME MEASURE(S): Cumulative conception rate by age, number of oocytes retrieved, and embryos transferred, and the influence of these factors on dropout rates. RESULT(S): The cumulative conception rate and cumulative live birth rate after four attempts were 75% and 66%, respectively. The cumulative conception rate differed significantly between women 35 years of age or younger and those older than 35 years who had five or more oocytes retrieved (83% vs. 63%). When fewer than five oocytes were retrieved in women 35 years of age or younger, the cumulative conception rate decreased to 33%. Overall, 36% of patients continued treatment after the first attempt; these patients were more likely to have more than five oocytes retrieved and more than two embryos available for transfer. The cumulative conception rate was greater when the female partner was 35 years of age or younger and had more than five oocytes retrieved and more than two embryos were available for transfer. These factors influenced dropout rates.
InfertilityFecundabilityIVF OutcomesFertility Probability Models
The last decade has transformed the physician's approach to infertility. The development of IVF for its treatment has so improved our capacity to overcome this most distressing of disabilities that we now need to revise many of our working ideas on how it can come about. This is not because new causes have been discovered. Rather, an appreciation has been gained of how apparently minor disturbances can combine to cause a major disruption in the expectation of pregnancy.
At the best of times-and sometimes, no doubt, at the worst of times getting pregnant is a matter of chance. The parameter that describes this chance is the monthly probability of conception, known among epidemiologists as fecundability (f) (probability of achieving pregnancy in one menstrual cycle), and is similar to "monthly fecundity" (monthly probability of a live birth in one cycle exposed to the risk of pregnancy) (1). Like every statistic in biology, fecundability has a wide distribution of values in the population (modeled in Fig. 1). Figure 1 also illustrates a group of couples with a fecundability value of zero-meaning complete infertility, or sterility, which affects perhaps 5% of couples attempting to achieve a pregnancy.
PregnancyPreterm DeliveryIVF OutcomesSmall for Gestational Age
The Medical Research Council In-Vitro Fertilization (IVF) Register report on births resulting from assisted conception in Great Britain demonstrated a high incidence of preterm and low birthweight babies. This incidence remained high even when the analysis was restricted to singleton babies. The present paper investigates possible risk factors for prematurity, low birthweight and small-for-gestational-age (SGA) in singleton IVF births. Thirteen per cent of singleton IVF babies were preterm, 11% low birthweight and 17% small-for-gestational-age. Analysis by multiple regression indicated that hypertension during pregnancy was an independent risk for preterm delivery, low birthweight and SGA, bleeding during pregnancy for preterm delivery, and the number of embryos transferred and the type of infertility for low birthweight.