None listed
Conditions
Brief summary
Labour is perhaps the most hazardous time in pregnancy for the fetus. Uterine contractions can contribute to more than a halving of blood flow to the uterus and placenta and this in turn may lead to fetal distress. In most pregnancies, the placental blood supply and function is adequate but it may not be sufficient to tolerate the extra demands of labour. Up to 63% of babies who become distressed and suffer oxygen deprivation in labour have no prior risk factors. Furthermore, events in labour account for as many as 20% of cases of cerebral palsy in term infants. Recent research demonstrates that the changes in blood flow to the fetus can be detected by ultrasound and that these changes are highly predictive of identifying fetuses at risk of becoming distressed in labour, as well as reliably excluding those that were not at risk. With this in mind, investigating ways to preserve and promote the blood supply and in turn, the oxygenation to the fetus has the potential to significantly change intrapartum care. Sildenafil is a vasodilator (opens blood vessels) and based on previous research may play a role in enhancing blood flow to the fetus. This clinical trial will investigate if having sildenafil in labour improves the blood flow to the fetus and reduces the need for emergency operative delivery (either caesarean section or operative vaginal birth) for fetal distress.
Interventions
Participants will be randomised to either placebo orally 8 hourly (maximum three doses in 24 hours) or sildenafil citrate 50mg orally 8 hourly (maximum 150mg in 24 hours).
Only women at term (37-42 weeks of pregnancy) are eligible. Participants will be randomised when delivery is anticipated within 72 hours and dosing regimen commenced when transferred to birth suite for management of labour. Doses will be administered intrapartum in labour ward by medical and midwifery staff under supervision
Participants will be randomised to either placebo orally 8 hourly (maximum three doses in 24 hours) or sildenafil citrate 50mg orally 8 hourly (maximum 150mg in 24 hours). Only women at term (37-42 weeks of pregnancy) are eligible. Participants will be randomised when delivery is anticipated within 72 hours and dosing regimen commenced when transferred to birth suite for management of labour. Doses will be administered intrapartum in labour ward by medical and midwifery staff under supervision and unused drug tablets will be returned and disposed of in adherence with hospital policy.
Sponsors
Mater Health Service
Study design
Allocation
Randomised controlled trial
Intervention model
Parallel
Primary purpose
Treatment
Masking
Blinded (masking used) (Subject, Caregiver, Investigator, Outcomes Assessor)
Eligibility
Sex/Gender
All
Age
18 Years to 50 Years
Healthy volunteers
Yes
Inclusion criteria
*Aged between 18-50 who are able to give informed consent *Singleton pregnancy at 37-42 weeks gestation *Appropriately grown fetus without any structural, chromosomal or genetic abnormality. *Admitted in spontaneous labour (cervical dilatation <4cm) or prior to induction of labour *Planning a vaginal delivery
Exclusion criteria
*Women <18 years old *Those unable to give informed consent *Women with pre-existing heart disorders, stroke, hypotension or hypertension, retinitis pigmentosa, kidney or liver abnormalities, sickle cell anaemia, stomach ulcers or any other bleeding disorder. *Women on any anti-hypertensive medication.
Outcome results
None listed