The effectiveness of immediate versus delayed tubal flushing with oil-based contrast in women with unexplained infertility (H2Oil-timing study): study protocol of a randomized controlled trial

Table 2 SPIRIT schedule of enrollment, intervention and assessments

	Study period
	Enrollment	Allocation	Post-allocation
TIMEPOINT	-t₁	t₀	t₁	t₂	t₃	t₄
ENROLLMENT:
Eligibility screening	X
Informed consent	X
Allocation		X
INTERVENTIONS:
Immediate oil-HSG			X
Delayed oil-HSG				X
ASSESSMENTS:
Baseline characteristics		X
APAIS questionnaire*			X or X
Pain score*			X or X
HSG procedure, results and complications*			X or X
iMCQ				X	X
iPCQ				X	X
Fertility treatment					X
Pregnancy yes/no				X	X
Ongoing pregnancy outcome						X

*Depending on the allocated intervention. -t₁: prior to allocation, t₀: at allocation, t₁: first menstrual cycle after allocation, t₂: 6 months after allocation, t₃: 12 months after allocation, t₄: 2 months post-partum

ISSN: 1472-6874