An uploaded screenshot shows the 32-year-old singer donated $10,000 to the nonprofit organization.
Perry wrote that she vows "to support organizations that may have their funding support taken from them in the future by the government," and she shared a personal testimony.
"I am making a public donation to Planned Parenthood for the teenage me who made several visits to first a clinic in Santa Barbara and then Los Angeles, CA to educate myself on my sexual health, a subject I had little to no information on because of my sheltered upbringing," she wrote. "Planned Parenthood educated me on my body and my reproductive health, so that I could focus on my dreams and using my voice until I knew the timing was right for me to make a plan to have a family ... Without this education, I may have had a different life path."
The "Roar" singer personalized the message by referring to herself with her legal name, as opposed to her stage name, and she expressed her belief in the need for women to plan ahead.
"I am grateful for and stand in support of Planned Parenthood for giving Katheryn Hudson the knowledge to plan and for continuing to be a haven for women to learn all options for their future," she wrote. "Now, more than ever, we all need to protect and create safe places for each other."
Perry, who wrote that she grew up with "a lower- to middle-class family" that didn't have health insurance options, encouraged other women to "become a member and an ally" of Planned Parenthood.