The Duchess of Sussex says the decision by the United States Supreme Court to roll back abortion rights tells women they "don't matter".
Meghan has also spoken of her and Harry's "guttural" reaction to the decision, saying: "He's a feminist too."
The US Supreme Court last week ended constitutional protections for abortion that have been in place for nearly 50 years by deciding to overturn the landmark Roe v Wade ruling.
In a conversation with American feminist activist Gloria Steinem and journalist Jessica Yellin, published in Vogue, she said: "Women are already sharing stories of how their physical safety is being put in danger.
"Women with resources will travel to get an abortion, those without might attempt to give themselves one at tremendous risk."
She explained some will be forced to find abortion pills from unregulated pharmacies and "be at the mercy" of doctors and lawyers.
"What does this tell women?" she added. "It tells us that our physical safety doesn't matter, and as a result that we don't matter. But we do. Women matter."
The duchess said the court's decision was going to have a disproportionate effect on women of colour and that is was "difficult to overstate" what it would mean for them.
However, it is not just a women's issue, she told the magazine, with the ruling representing "a blueprint for reversing rights", including same-sex marriage and contraception access, and called on men to get involved.
She said: "Men need to be vocal in this moment and beyond because these are decisions that affect relationships, families, and communities at large.
"They may target women, but the consequences impact all of us. My husband and I talked about that a lot over the past few days. He's a feminist too."
She continued: "His reaction last week was guttural, like mine. I know that for so many women right now, there is a sentiment of despair. But, again, we have to band together and not wallow. We have to do the work."
Meghan was back in the UK for the Platinum Jubilee earlier this month with the Duke of Sussex, Archie and Lili.
She made an appearance with Harry at the service of thanksgiving held to mark the Queen's milestone.
Australian Associated Press
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