Couples in whom the results of an initial fertility workup fail to identify the presence of any obvious barriers to conception are diagnosed with unexplained subfertility. Couples who have tried to conceive for a relatively short time have a good chance of natural conception and thus may not benefit from immediate access to ART. As fertility decreases over time, the main dilemma that clinicians and couples face is when to abandon an expectant approach in favour of active treatment. Several prognostic or predictive models have been used to try to discriminate between couples with high and low chances of conception but have been unable to compare individualized chances of conception associated with ART relative to chances of natural conception at various time points. These models are also unable to recalculate the chances of pregnancy at subsequent time points in those who return after a period of unsuccessful expectant management. In this paper, we discuss currently available models. We conclude that in order to provide accurate, individualized and dynamic fertility prognoses associated with and without treatment at different points in time, we need to develop, validate and update clinical prediction models which are fit for purpose. We suggest several steps to move the field forwards.
The author group would like to thank Prof. Egbert te Velde for all of his efforts regarding the present manuscript, including his work on the first draft and his insightful remarks during the process.
B.W.M. is supported by a NHMRC Practitioner Fellowship (GNT1082548)
- Journal Article
- unexplained subfertility
- natural conception
- prediction models
- dynamic prediction