NCT06105775

Inorganic Nitrate Supplementation in Chronic Hypertensive Pregnancies

Inorganic Nitrate Supplementation for Blood Pressure Control in Chronic Hypertensive Pregnancies From the 2nd Trimester (NIT_CH): a Triple-Blind Randomized Placebo-Controlled Trial

• Status: Recruiting
• Phase: N/A
• Study type: Interventional
• Enrollment: 144 (estimated)
• Sponsor: University of Sao Paulo · Academic / Other
• Sex: Female
• Age: 16 Years
• Healthy volunteers: Not accepted

Summary

High blood pressure during pregnancy poses significant risks to both the mother and baby. A combination of factors, including advancing maternal age, rising obesity rates, and metabolic health issues, have amplified the prevalence of this condition. While conventional medicines are available, safety during pregnancy remains a concern. Recent studies suggest that inorganic nitrate might be a safer alternative. The power of nitrate lies in its ability to stimulate the body's production of a compound that aids in dilating and relaxing blood vessels. Preliminary studies conducted on mice and a select group of pregnant women have yielded encouraging results. Early tests indicated that after consuming inorganic nitrate, there was a reduction in blood pressure and an improvement in the health of the mother's uterine artery-a vital vessel responsible for nourishing the fetus. Our study aims to investigate the effects of inorganic nitrate supplementation on pregnant women from the start of their pregnancy and continuing it throughout their term. If our findings are positive, it could revolutionize how we approach blood pressure management during pregnancy, paving the way for healthier futures for both mothers and babies.

Detailed description

Eligible pregnant women with chronic hypertension will be identified and invited to participate through posters displayed in the municipality's health units, as well as by medical professionals within the local health network, based on the inclusion criteria. An appointment will be promptly scheduled to verify eligibility and present the informed consent form, during which all questions and concerns will be addressed. On the enrollment day, the subsequent visit will be scheduled for the 16th week of their pregnancy, marking the commencement of the study. By then, participants will already have been randomly allocated to respective groups by an external professional who is not directly involved in the study, ensuring blinding. Randomization will occur on a 1:1 ratio, employing blocks of 2-4 pregnant women as determined by specialized software. Regardless of allocation, participants will continue with standard medications for preeclampsia prophylaxis: acetylsalicylic acid, taken at 100 mg nightly up to 36 weeks of gestation, and calcium carbonate, taken at 1000 mg daily until delivery, alongside routine antihypertensive treatment. From the 16th week of pregnancy onward, participants will receive either a capsule containing 400 mg of inorganic nitrate (540 mg of sodium nitrate, equivalent to 140 mg of sodium chloride and 400 mg of nitrate) or a placebo (140 mg of sodium chloride and 400 mg of flour). Both capsules will be identical in color and appearance. All participants will be instructed to take one capsule each morning, continuing this regimen for 22 weeks (154 days), ending either at the 38th week of pregnancy or at childbirth, whichever occurs first. Visits will take place at predetermined intervals based on the progression of the pregnancy. Initially set at a frequency of every 4 weeks, but as the end of the pregnancy approaches, the visits will become more frequent. The baseline appointment is set for the 16th week of gestation, with subsequent appointments scheduled for the 20th, 24th, 28th, 32nd, 34th, 36th, 37th, and 38th weeks. It is important to note that scheduled visits may conclude earlier if childbirth occurs sooner, or they might be extended if the pregnancy progresses beyond the anticipated delivery date. During these visits, participants will undergo an obstetric clinical examination, blood pressure measurement, biochemical analysis, and an ultrasound paired with a Doppler study of the uterine arteries. To ensure consistent and optimal blood pressure levels, the overseeing medical team will closely monitor and adjust participants' antihypertensive medications as necessary. Ensuring adherence to the regimen is paramount; thus, participants will be asked to return any unused capsules during their visits and will then be supplied with their next batch for the ensuing period.

Conditions

• Hypertension in Pregnancy
• Hypertension
• Pregnancy

Interventions

Type	Name	Description
DIETARY_SUPPLEMENT	Inorganic Nitrate Capsule	Starting from the 16th week of gestation and continuing for 22 weeks (154 days) or until delivery, whichever comes first, participants will consume a daily capsule containing 400 mg of inorganic nitrate. Participants will maintain standard preeclampsia prophylaxis (acetylsalicylic acid 100mg nightly until 36 weeks of gestation and calcium carbonate 1000mg daily until delivery) and regular antihypertensive treatment.
DIETARY_SUPPLEMENT	Placebo Capsule	From the 16th week of gestation and lasting 22 weeks (154 days) or until delivery, participants will consume a daily capsule containing sodium chloride with the nitrate replaced by plant-based flour, design to mimic the appearance of the active capsule. Participants will maintain standard preeclampsia prophylaxis (acetylsalicylic acid 100mg nightly until 36 weeks of gestation and calcium carbonate 1000mg daily until delivery) and regular antihypertensive treatment.

Timeline

• Start date: 2025-03-06
• Primary completion: 2025-12-01
• Completion: 2026-12-01
• First posted: 2023-10-30
• Last updated: 2025-03-26

Locations

1 site across 1 country: Brazil