Rationale: The investigators hypothesize that direct tubal flushing with oil-based contrast at HSG incorporated in the fertility work-up results in 10% more ongoing pregnancies and a shorter time to pregnancy compared to delayed tubal flushing 6 months after fertility work-up is completed in women at low risk for tubal pathology, which will lead to a reduction in the need for expensive fertility treatments like IVF and/or ICSI, and will therefore be an effective and cost effective strategy.~Objective: The aim of this study is to determine whether direct tubal flushing with oil-based contrast at HSG incorporated in the fertility work-up results in 10% more ongoing pregnancies and a shorter time to pregnancy, which will therefore be effective and cost-effective compared to delayed tubal flushing 6 months after fertility work-up is completed in women at low risk for tubal pathology.~Study design: The investigators plan a multicentre randomized controlled trial with an economic analysis alongside it. Infertile women at low risk for tubal pathology will be randomized to direct tubal flushing with oil-based contrast incorporated in the fertility work-up or delayed tubal flushing 6 months after fertility work-up is completed.~Study population: Infertile women 18-38 years of age, who have a spontaneous menstrual cycle and at low risk for tubal pathology, undergoing fertility work-up.~Intervention (if applicable): Direct tubal flushing with oil-based contrast at HSG as part of the fertility work-up compared to delayed tubal flushing 6 months after the fertility work-up is completed.~Main study parameters/endpoints: The primary outcome is time to live birth, calculated from positive pregnancy test and within 12 months after randomization.~Our hypothesis is that tubal flushing at HSG with oil-based contrast incorporated in the fertility work-up will result in 10% more ongoing pregnancies and a shorter time to pregnancy, and thus reducing the need for ART and reducing costs.~Nature and extent of the burden and risks associated with participation, benefit and group relatedness: As two strategies are compared (tubal flushing with oil-based contrast at HSG incorporated in the fertility work-up versus 6 months after completion of fertility work-up) that are already applied in current practice, no additional risks or burdens are expected from the study.
The aim of this study is to determine whether direct tubal flushing with oil-based contrast at HSG incorporated in the fertility work-up results in 10% more ongoing pregnancies and a shorter time to pregnancy, which will therefore be effective and cost-effective compared to delayed tubal flushing 6 months after fertility work-up is completed in women at low risk for tubal pathology.