What is the use of low-dose Acetylsalicylic acid (ASA) in pregnancy?

From the Guidelines

Low-dose Acetylsalicylic acid (ASA) is used in pregnancy to prevent preeclampsia, particularly in high-risk individuals, with a recommended dose of 100-150 mg/day starting at 12 to 16 weeks of gestation.

Key Points

• The use of low-dose ASA in pregnancy is supported by the U.S. Preventive Services Task Force, which recommends its use in individuals at high risk for preeclampsia, such as those with type 1 or type 2 diabetes 1.
• The recommended dose of low-dose ASA is 100-150 mg/day, with some studies suggesting that a dose of 162 mg/day may be acceptable 1.
• Low-dose ASA has been shown to reduce the risk of preeclampsia by 24%, preterm birth by 14%, and intrauterine growth restriction (IUGR) by 20% 1.
• The American Congress of Obstetricians and Gynecologists, the World Health Organization, and the National Institute for Health and Care Excellence also recommend the use of low-dose ASA in high-risk pregnant women 1.

Benefits and Harms

• The benefits of low-dose ASA in pregnancy include the prevention of preeclampsia, preterm birth, and IUGR 1.
• The harms of low-dose ASA in pregnancy are considered to be small, with no increased risk of placental abruption, postpartum hemorrhage, or fetal intracranial bleeding 1.

Clinical Considerations

• The decision to use low-dose ASA in pregnancy should be based on an individual's risk factors for preeclampsia, such as medical history and clinical diagnostic tests 1.
• Low-dose ASA should be started at 12 to 16 weeks of gestation and continued until delivery 1.

From the FDA Drug Label

If pregnant or breast-feeding, ask a health professional before use. It is especially important not to use aspirin at 20 weeks or later in pregnancy unless definitely directed to do so by a doctor because it may cause problems in the unborn child or complications during delivery. The use of low-dose Acetylsalicylic acid (ASA) in pregnancy is not explicitly stated in the label, but it warns against using aspirin at 20 weeks or later in pregnancy unless directed by a doctor.

• Pregnancy warning: Aspirin may cause problems in the unborn child or complications during delivery if used at 20 weeks or later in pregnancy.
• Precaution: Pregnant women should ask a health professional before using aspirin 2.

From the Research

Use of Low-Dose Acetylsalicylic Acid (ASA) in Pregnancy

• The use of low-dose ASA in pregnancy has been studied for its potential to prevent preeclampsia and other adverse pregnancy outcomes 3, 4, 5, 6, 7.
• Low-dose ASA is recommended for women at high risk of preeclampsia, including those with a history of preeclampsia, multifetal gestation, renal disease, autoimmune disease, type 1 or type 2 diabetes, and chronic hypertension 4.
• The optimal dosage and timing of low-dose ASA treatment are still under investigation, but current guidelines suggest initiating treatment between 12 weeks and 28 weeks of gestation, optimally before 16 weeks, and continuing daily until delivery 4.
• Studies have shown that low-dose ASA can reduce the risk of preeclampsia, intrauterine growth restriction, and preterm birth in high-risk pregnant women 5, 6, 7.
• The effectiveness of low-dose ASA in preventing preeclampsia and other adverse outcomes may depend on the individual patient's response to the treatment, with some studies suggesting that a personalized approach to ASA therapy may be necessary 5.

Benefits and Risks of Low-Dose ASA in Pregnancy

• Low-dose ASA has been shown to be safe and effective in preventing preeclampsia and other adverse pregnancy outcomes, with a low risk of serious maternal or fetal complications 4, 7.
• However, some studies have suggested that low-dose ASA may not be effective in all women, and that a higher dose may be necessary to achieve optimal benefits 5.
• Further research is needed to fully understand the benefits and risks of low-dose ASA in pregnancy and to develop personalized treatment approaches for individual patients 3, 5, 6.