Calculate the probability of a spontaneous ongoing pregnancy within 1 year
(leading to live birth).

This probability is not reliable in case of :
Has a postcoital test been performed?

This model has been validated between 2002-2004 in 38 hospitals in the Netherlands by Van der Steeg et al. In the Colaborative Effort of Clinical Evaluation in Reproductive Medicine (CECERM). The models showed to predict accurately.