Evaluation of Low-Dose Acetylsalicylic Acid for Preeclampsia Prevention in Pregnant Women Post-Frozen Embryo Transfer: A Randomized Controlled Trial

The primary objective of this study is to evaluate the **incidence of preeclampsia** in pregnant women who have undergone frozen embryo transfer and are treated with 160 mg of **acetylsalicylic acid** (ASA) compared to those who receive no treatment. Preeclampsia is a significant hypertensive disorder during pregnancy that can lead to severe complications for both the mother and the fetus. Identifying effective preventive measures is crucial for improving maternal and fetal outcomes. The study aims to determine whether low-dose ASA can reduce the risk of developing preeclampsia in this specific population.

The clinical trial focuses on evaluating the incidence of **preeclampsia** in a specific population of women who have undergone a frozen embryo transfer. The study population consists exclusively of healthy females aged between 18 and 43 years. Participants are required to have a confirmed pregnancy at six weeks of amenorrhea and must have provided informed consent. The trial does not include male subjects and involves a vulnerable population. The sponsor has not provided information regarding the total number of participants. Participants are selected based on their planned frozen embryo transfer, which may occur in a natural, modified natural, or hormone replacement therapy (HRT) cycle. Lifestyle factors such as diet, physical activity, or other habits are not specified in the available data.

The clinical trial is a **randomized controlled trial** designed to evaluate the effect of low-dose **acetylsalicylic acid** as a preventive treatment for **preeclampsia** in pregnant women who have undergone frozen embryo transfer. The trial will involve two groups: one receiving 160 mg of acetylsalicylic acid and the other receiving no treatment. The primary objective is to assess the incidence of preeclampsia in these women. The trial is expected to run from October 2022 to October 2025, with a maximum treatment period of 28 days for participants.

Participants will be required to attend several study visits throughout the trial. The initial visit will be a screening visit to confirm eligibility, which includes criteria such as being a healthy woman aged 18 to 43, planning for a frozen embryo transfer, and having a confirmed pregnancy at six weeks of amenorrhea. Informed consent must be obtained from all participants. Follow-up visits will be scheduled to monitor the health and progress of the participants, ensuring adherence to the treatment protocol and collecting data on the primary endpoint, which is the mean number of women suffering from preeclampsia in both groups. The end-of-study visit will conclude the participant's involvement, where final assessments will be conducted.

The expected length of participant involvement is up to 28 days, corresponding to the maximum treatment period. Conditions that may lead to early termination from the study include withdrawal of consent, adverse reactions to the treatment, or any medical condition that, in the investigator's opinion, would make continued participation detrimental to the participant's health. The trial is conducted under a double-blind design to ensure unbiased results, with neither the participants nor the investigators aware of the group assignments. This trial is categorized as a Phase 3 trial, indicating its advanced stage in the clinical research process.

The clinical trial involves the administration of **acetylsalicylic acid** as the experimental medication. The product used is Asaflow 80 mg, which is formulated as a **gastro-resistant tablet**. The active substance, acetylsalicylic acid, is of chemical origin. The medication is administered orally, with a maximum daily dose of 160 mg. The total maximum dose over the treatment period is 31,360 mg. The treatment duration is set for a maximum of 28 days. The trial aims to evaluate the preventive effect of low-dose acetylsalicylic acid on preeclampsia in pregnant women who have undergone frozen embryo transfer.

In this study, the experimental group receives the acetylsalicylic acid treatment, while the control group does not receive any treatment, serving as a comparator. The trial is designed to assess the incidence of preeclampsia between the two groups. Participant compliance with the dosing schedule is monitored throughout the study to ensure adherence to the treatment protocol. No additional non-experimental treatments, such as standard-of-care therapy or placebo, are utilized in this trial.

The efficacy of the clinical trial will be assessed by evaluating the primary endpoint, which is the mean number of women suffering from **preeclampsia** in the treated group versus the untreated group. The trial is designed as a prospective interventional randomized controlled trial to determine the effect of low-dose acetylsalicylic acid (ASA) as a preventive treatment for preeclampsia in pregnant women who have undergone frozen embryo transfer. The treatment involves administering 160 mg of ASA, and the efficacy will be measured by comparing the incidence of preeclampsia between the two groups.