A quick look at indexed news articles does not show any major news organization hits for the March For Life until near the bottom of the first page of hits (NBC Washington), and then only to note that traffic will be difficult as a result of tens of thousands of marchers. (Estimates from the actual event put it near 300,000.)
Surprised? Didn't think so.
The Washington Post had a link in the Local / Metro section that redirected to the Religion section. It definitely wasn't "above the fold". The article wasn't particularly biased when it correctly reported that
Few counter-demonstrators were visible along the route, but some gathered in front of the Supreme Court.but the accompanying video was heavily skewed to give the impression of a lot more counter-demonstrators and show a "balanced" report. (Example: the still for the video shows a "Keep Abortion Legal" sign holder.) In keeping with the Post's political leanings, the article titles used the "anti-abortion" appellation vs. the "pro-life" language.
Then there are the active truth twisters like Newsweek who assert that there are no young women attending the March for Life. No, I'm not linking to them.
They can skew all they like or try to create news blackouts by not covering it, but still - somehow - hundreds of thousands of people show up every year to protest abortion.