Table 1

Study timeline

	Study period
	Enrolment 19–23 weeks	Allocation 20–24 weeks	Postallocation 36–37 weeks	Close-out 28 days after delivery
Timepoint	T1		T2	T3
Eligibility screen	X
Informed consent	X
Allocation 20–24 weeks		X
Interventions
Concealed			X
Revealed			X
Assessments
Sociodemographic data		X
Medical history		X
Prenatal evaluation (ultrasound biometries)		X	X
Doppler assessment			X
Amniotic fluid assessment			X
Perinatal outcome				X