In November 2013, ACOG issued the Hypertension in Pregnancy Task Force Report recommending daily low-dose aspirin (81mg) beginning in the late 1st trimester for women with a history of early-onset preeclampsia and preterm delivery at less than 34 0/7 weeks, or for women with more than one prior pregnancy complicated by preeclampsia. The following year, the USPSTF published a similar guideline, although the list of indications for low-dose aspirin use was more expansive. Since then, the ACOG has issued new guidance on low-dose aspirin, in 2018 and 2021. Nonetheless, while criteria for use has evolved, the dosage recommended has remained as 81 mg. But MEDICINE MOVES FAST, and a new Expert Review in the AJOG MFM is making a case for 162mg. Are we underdosing low-dose aspirin for prevention of preeclampsia? A litany of data says YES. Listen in for details.