Unexplained subfertility Illuminating the path to treatment

This thesis illuminates the path from diagnosis to treatment for couples with unexplained subfertility. The crucial questions are if, when and how to treat. Any decision to start treatment should depend on the trade-off between four treatment dimensions: i.e. burden, effectiveness, safety, and costs in relation to treatment.
Common first-line treatments for couples with unexplained subfertility are intrauterine insemination (IUI) and in vitro fertilisation (IVF). Advancements in IVF have led to it being seen as a potentially more cost-effective and safer option compared to IUI. Yet IUI has also advanced in recent years. We performed a randomised controlled trial comparing two forms of IVF to IUI with ovarian stimulation as a first-line treatment in couples with unexplained or mild male subfertility and an unfavourable prognosis for natural conception. We also performed an economic analysis alongside this trial. We further evaluated whether there were treatment selection markers that could aid in identifying couples that would have had better pregnancy chances with IVF compared to IUI.
Natural conception rates are crucial to clinical decision-making, so we evaluated the natural conception chances for these couples. Additionally, we looked at differences between clinics in natural conception rates.
Finally, we are working on a systematic review and network meta-analysis incorporating all the available evidence of randomised controlled trials on first-line treatments and unassisted reproduction for couples with unexplained subfertility.