Duration of Subfertility as a Prognostic Factor

Abstract

Objectives: Longstanding subfertility is associated with a low chance to conceive spontaneously. Treatment modalities are intra-uterine insemination in hyperstimulated cycles and in vitro fertilization (ART). These treatments are expensive and have a considerable physical and psychological impact on the patient. In the initiation of ART the chances to conceive without treatment should be weighed against success of treatment. To what extent does duration of subfertility predict the chance of spontaneous conception? Design: Retrospective cohort study in a university-based hospital. Materials and Methods: In 1997 369 couples were registered at the outpatients clinic for Reproductive Medicine of the University Hospital Groningen. A routine subfertility screening was performed. Exclusion criteria were: ovulatory disorders, azoospermia, bilateral tubal occlusion, any subfertility treatment and lost to follow-up. Results: 238 couples fulfilled the criteria for inclusion. The table summarizes the data of patients that did and did not become pregnant stratified for duration of subfertility. legendlegendSensitivity: 35%, Specificity: 82% Sensitivity: 16%, Specificity: 98% Positive likelihood ratio: 1.94 Positive likelihood ratio: 8.00 Negative likelihood ratio: 0.79 Negative likelihood ratio: 0.86Not pregnantPregnantTotalNot pregnantPregnantTotal> 2 yrs68876> 3 yrs31132< 2 yrs12636162< 3 yrs16343206Total19444238Total19444238legend Sensitivity: 35%, Specificity: 82% Sensitivity: 16%, Specificity: 98% Positive likelihood ratio: 1.94 Positive likelihood ratio: 8.00 Negative likelihood ratio: 0.79 Negative likelihood ratio: 0.86 Open table in a new tab Conclusions: A subfertility duration of 2 years does not predict a failure to conceive spontaneously in the next year very well. A 3 year duration of subfertility is a very good prognostic test to predict ongoing childlessness. This confirms the general practice in the Netherlands to start ART only after three years of unexplained subfertility.