This clinical trial aims to determine the effect of PUFA-n3 supplementation on birth weight, gestational length, and plasma inflammatory markers in pregnant women with HIV who are on antiretroviral therapy. The key questions this study seeks to answer are:

1. Will the neonates of HIV-positive women who received 1280 mg of PUFA-n3 supplementation during pregnancy have higher birth weights and longer gestation periods compared to the neonates of HIV-positive women who received a placebo?
2. Will the inflammatory markers in HIV-positive women who received 1280 mg of PUFA-n3 during pregnancy differ from those of HIV-positive women who received a placebo?

Researchers will compare the effects of 1280 mg of PUFA-n3 supplementation against a placebo (olive oil) to determine if the supplement can increase birth weight, gestational length, and attenuate the inflammation.

Participants in the study will:

• Take a prenatal multivitamin that includes 300 mg of PUFA-n3
• Take either 1280 mg of PUFA-n3 or a placebo daily for 8 weeks, starting from a gestational age of 20-29 weeks.
• Visit the hospital at the beginning of the study and again 8 weeks later for blood sampling. Additionally, they will have follow-up visits every 2 weeks to monitor gestational weight gain and dietary intake.
• Keep a diary to register their supplement intake and record any side effects.

In pregnant women infected with human immunodeficiency virus (HIV), antiretroviral therapy (ART) during pregnancy significantly reduces the risk of neonatal or vertical transmission of the virus. However, these women may face a higher risk of adverse outcomes for their babies, including preterm birth, low birth weight, and being small for their gestational age. HIV infection and ART contribute to a chronic inflammatory state, which has been linked to these negative pregnancy outcomes.

Additionally, the typical diet of pregnant women receiving perinatal care at the Instituto Nacional de Perinatología often lacks sufficient polyunsaturated fats. This is primarily due to limited access to a diverse and high-quality diet, which is frequently influenced by their socioeconomic status. Supplementation with polyunsaturated omega-3 fatty acids (PUFA-n3) during pregnancy has been proposed as a preventive measure against adverse outcomes such as preterm birth and low birth weight. Several studies have documented the efficacy of PUFA-n3 supplementation in this population, particularly among women with a low dietary intake of these fatty acids.

Moreover, even though ART reduces inflammation and immune activation, these levels remain elevated compared to those in healthy individuals, and the imbalance in cytokine profiles persists. ART can also alter cytokine profiles, highlighting the critical need for interventions aimed at reducing chronic inflammation, which can ultimately impact morbidity and mortality in this population.

The relationship between insufficient intake of PUFA-n3 and preterm birth can be attributed to its role in the physiology of delivery. A high ratio of PUFA-n6 to PUFA-n3 may trigger early labor. Therefore, this study aims to evaluate the effects of PUFA-n3 supplementation on birth weight, gestational length, and plasma inflammatory biomarkers in pregnant women using ART.

The sample size for this study was calculated for all the outcome variables. The largest sample size will be used, which was the one calculated to find differences between the means in the IL-6 concentrations of the two supplementation groups, accepting a type I error of 0.05, α=0.05 (1.96), aiming to show a true difference with 0.80 probability, β=0.20 (-0.84). A study in pregnant women was taken as a reference, where the intervention was carried out with a similar dose of PUFA-n3 (1200 mg). The difference found in IL-6 concentrations was 2.8 pg/mL, and following the standard deviation observed in the same study of IL-6 of 4.4 pg/mL. As a result, the sample size will be 38.7 patients per group, plus 20% losses, so 46 patients per group.

The women who meet the inclusion criteria will be invited to participate, and an informed consent letter will be explained and given. Those women who accept will be enrolled in the study. First, they will be randomly assigned to one of the supplementation groups: softgels with 1280mg of PUFA-Ω3 or softgels with a placebo (olive oil).

Allocation to the treatment groups will be done using a table of random numbers, through the software for parallel group clinical trials: Random Allocation Software, created in Microsoft Visual Basic 6 for Windows. Both groups of women will have their usual prenatal care, which includes the Nutrition Care Process. There will be two evaluations, the initial between 20 to 29 weeks of gestational age (GA) according to the first day of the last menstrual period, and the second one, eight weeks after the first (28-37 GA). Both evaluations included: medical history, multiple-pass 24-hour dietary recall, weight measurements, and blood sampling for the inflammatory biomarkers and fatty acid quantification. The pregnancy outcomes, birth weight, and gestational length are going to be obtained from the electronic file. Finally, the statistical analysis will be according to the distribution of outcome variables. The change in the inflammatory biomarkers and the change in the erythrocyte fatty acid profile will be analyzed by a paired t-test or Wilcoxon test. Afterwards, the effect of the supplementation on the pregnancy outcomes and inflammatory biomarkers will be evaluated by the Student t-test or the U-Mann-Whitney test.

Inclusion Criteria:

• Pregnant women
• Single pregnancy
• Gestational age from 20 to 29 weeks since the first day of the last menstrual period
• Agree to participate in the study

Exclusion Criteria:

• Gestational age more than 29 weeks
• With diagnosis of gestational diabetes or preeclampsia
• Smoking and/or drug use during the invitation to participate in the study
• Fish allergy

Only IPD that will be used in the results publication

At the beginning of the study, and until the end of the study

Who wanted to know more about this study, and when the results were published, if it is required.