You can get DHA from algea sources and still eat vegan. There is also a sex-linked difference between ALA conversion to DHA/EPA, with women, and women who are

You can get DHA from algea sources and still eat vegan. There is also a sex-linked difference between ALA conversion to DHA/EPA, with women, and women who are pregnant or brestfeeding converting significantly more ALA to DHA than men. Men were converting far less than 10% while women were converting more than 10%.