Dunham showed up to a Planned Parenthood event wearing an eye-catching sweater that she first brought attention to via Instagram.
"Rollin to the @plannedparenthood Los Angeles Champion of Choice event and there was only one sweater that would do @rachelantonoff," she captioned the pic.
The burgundy sweater had a pink ovary shape on it, and was designed by Rachel Antonoff, the sister of Dunham's boyfriend Jack.
Dunham didn't wear the sweater home that night but instead took it right off her back and handed it to the highest bidder. "The @plannedparenthood event in LA tonight was so crazy inspiring," she captioned a selfie of her bra. "I also spontaneously auctioned the ovary patterned sweater off my body for a nice 4k to benefit PP... Had to walk home in my skivvies and a men's coat #worthit #onbrand #standwithPP."
While she didn't take her shirt off during her visit toThe Ellen DeGeneres Show, she did get pretty candid as to why she and Antonoff have yet to get engaged.
"We were celebrating, and then suddenly the texts just started coming from our friends, from our mothers, from our exercise instructors being like, 'Finally, it's your time.' And we kind of looked at each other and were like, 'Oh God, what have we done?'" she recalled, admitting they were "hiding behind fake liberal ideals."
She did reveal that she still plans on saying "I do" to Antonoff -- just not right now.
"We're not gonna suddenly just get engaged because it became legal," she said. "We better wait for a moment where we feel excited about this. I'm excited to marry him at some point, but it felt like a lot of pressure to just go for it that day.
Dunham quipped, "I did start to ask are there a lot of heterosexuals using this as an excuse to avoid commitment."
Check out more of the Girls star's interview on Ellen: