NCT03581214: O2P2

Intrapartum Maternal Oxygen Supplementation: Effects on the Mother and Neonate

Completed NA Results posted Last updated 15 April 2025

What this trial tests

NA trial testing No oxygen in Intrauterine Resuscitation in 910 participants. Completed in 1 April 2024.

Timeline

15 July 2018

Primary endpoint
17 October 2022

1 April 2024

Quick facts

Lead sponsor	Washington University School of Medicine
Phase	NA
Status	Completed
Study type	INTERVENTIONAL
Allocation	randomized
Design	parallel
Masking	double
Primary purpose	treatment
Enrollment	910
Start date	15 July 2018
Primary completion	17 October 2022
Estimated completion	1 April 2024
Sites	1 location across United States

Drugs / interventions tested

• No oxygen
• Oxygen — full drug profile →

Conditions studied

• Intrauterine Resuscitation — all drugs for Intrauterine Resuscitation →

Sponsor

Washington University School of Medicine

Who can join

18 and older, female only, with Intrauterine Resuscitation. Patients with the condition only — healthy volunteers not accepted.

Results — posted to ClinicalTrials.gov

Per-arm endpoint measurements with 95% confidence intervals where reported. Source: trial results section.

Umbilical Artery Malondialdehyde Primary · At delivery

Group	Value	95% CI
Room Air	9.8	6.2 – 17.4
Oxygen	10.2	6.6 – 15.8

Umbilical Artery 4-hydroxynonenal Primary · At delivery

Group	Value	95% CI
Room Air	34.1	10.6 – 155.2
Oxygen	29.5	10.6 – 145

Maternal Malondialdehyde Primary · Within 1 hour of delivery

Group	Value	95% CI
Room Air	2.8	2.1 – 3.9
Oxygen	2.5	1.8 – 3.6

Maternal 4-hydroxynonenal Primary · Within 1 hour of delivery

Group	Value	95% CI
Room Air	190.4	82.3 – 292.2
Oxygen	168.1	65.9 – 312.5

Adverse events — posted to ClinicalTrials.gov

Time frame: 72 hours post delivery. Reporting threshold: 0%. Adverse-event reports describe events observed during the trial — not all are caused by the drug.

Room Air

Serious: 0/102 (0%)

Deaths: 0/102

Oxygen

Serious: 0/104 (0%)

Deaths: 0/104

Other adverse events (2 terms — click to expand)

Reaction	System	Room Air	Oxygen
Neonatal ICU stay > 72 hours	Pregnancy, puerperium and perinatal conditions	—	—
Neonatal hypothermia treatment	Pregnancy, puerperium and perinatal conditions	—	—

Data from ClinicalTrials.gov NCT03581214 adverse events section.

Sponsor's own description

Approximately 2/3 of laboring women receive supplemental oxygen (O2) in an attempt to reverse perceived fetal hypoxia on electronic fetal monitoring (EFM). O2 supplementation is most commonly used in patients with Category II EFM, a class of EFM patterns designed in part to identify fetal acidemia. This liberal use of O2 in laboring patients is concerning because hyperoxygenation in infants is associated with adverse outcomes including retinopathy and abnormal neurodevelopment. Furthermore, excess O2 exposure is linked to free radical generation and subsequent oxidative cell damage. This calls for a closer look at the safety of intrauterine O2 exposure. The proposed project explores potential mechanisms for harm with maternal O2 supplementation in laboring patients with Category II EFM. Specifically, this project will determine the effect of O2, compared to room air (RA), on umbilical cord and maternal levels of malondialdehyde (MDA) and 4-hydroxynonenal (4-HNE), markers of free radical-induced oxidative stress. The study will also explore the correlation between urinary and blood markers of oxidative stress. Banked specimens will be used to investigate the potential effect of peripartum O2 exposure on placental oxidative stress in the future.

Publications & conference data

No peer-reviewed publications indexed yet for this trial. Completed trials usually publish results within 12-18 months.