The spontaneous pregnancy prognosis in untreated subfertile couples: the Walcheren primary care study

The spontaneous pregnancy prognosis of couples in a primary care situation has never been studied. Prognostic models have been developed for referral populations only. We wished to develop a prognostic model to estimate the likelihood of live birth and the impact of prognostic factors among untreated subfertile couples in a primary care situation. With this aim, we conducted a cohort follow-up study of 726 couples in the peninsula of Walcheren, a geographically isolated, but demographically and socio-economically representative area of an industrialized Western society, The Netherlands. Of the Walcheren population, 9.9% exhibit subfertility complaints at least once during their lifetime. There were 201 live birth conceptions during 9915 months of untreated observation. The cumulative rate of conceptions leading to live births was 52.5% when all of the untreated observations were considered, and 72.0% in the subgroup of 342 couples who remained untreated throughout their follow-up. The relevant prognostic factors in this primary care subfertility population were: abnormal post-coital test, tubal defect, ovulation defect, and duration of subfertility. A prediction score based on these factors would be accurate in approximately 76-79% of cases. Live birth prognosis can be estimated with sufficient accuracy to be useful in counselling subfertility patients, and in planning clinical management.