She's never been afraid to speak her mind, often vocal about causes such as Human Rights and Feminism.

And it seems Lena Dunham isn't shy about sharing her body as well as her opinions - as she posted a very natural bikini picture on Instagram stories on Wednesday.

The Girls actress, 30, posted a snap of herself holding her stomach in the bathroom mirror, sporting leopard print bottoms and a frilly black bikini top.

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Honest:Lena Dunham shared a series of bikini selfies on Instagram stories on Wednesday ahead of a pool party, writing: 'Endo scars and all'

She captioned the snap: 'Endo scars and all', referring to her Endometriosis scars, as she recovers from the chronic disease where the tissue that lines the uterus grows in other places in the body.

This usually means on the ovaries, in the abdominal cavity, and on the bladder and major organs like the liver and kidneys (though, in rare cases, the errant tissue has been found as far away as the brain).

The menstrual cycle causes the tissue to swell and bleed, causing pain, fatigue, nausea, gastrointestinal problems, and a host of other physical symptoms.

A pretty piece: The Girls actress, 30, showed off her Target ensemble as she connected with her fans

Funky: A flash of Lena's arm inking was in view as she pointed at the camera

On Tuesday Lena wrote she's 'dealt with [her] share of Internet trolls,' often finding herself 'disappointed' with the sites themselves for what she perceived to be 'a lack of effort to protect people online from racist, misogynist, ableist, xenophobic & transphobic language,' as well as blatant threats.

This comes the day after Instagram's CEO Kevin Systrom said the features were developed to foster a 'positive and creative' social media site considered 'a safe place for self-expression' for its users.

Happy day: Lena Dunham on Tuesday said she was pleased at Instagram's latest features that enables users to block out certain phrases they deem offensive; here she is seen in June

The last straw: Dunham said she stopped logging onto Twitter amid cruel abuse in reaction to this 2015 shot in which she was wearing her boyfriend's underwear

Drawing a line: Dunham said that while she's able to process the unending barbs from trolls, she worries about those who might not have the wherewithal to blow off the abuse

Turning things around: Dunham immediately pledged her support to the tech company amid its latest decision

'Social media communities should engender a dialogue,' the 30-year-old Girls creator said, 'not become tools for verbal abuse.'

Dunham, a 2008 graduate of Oberlin College, said that she understands that 'as a public person,' she's more prone to attacks, expressing concern for those who haven't been provided with the tools to brush off the effects of online bullying.

'I can't help but wonder how people without the same resources have learned to cope,' the Golden Globe winner said. 'What about teenagers who are still forming their identities, and for whom cyber-abuse is an absolute threat to their mental health?

Pretty as a picture: The Gotham native encouraged her fans to remain blocking and reporting those who harass and troll online

Dunham said she was pleased at Instagram's latest tweak, joking that the phrases she's personally eliminated from her feed include 'thong' and 'bag of cottage cheese,' among others.

'I'm so excited that they've given us this tool to keep unnecessary negativity out of our feeds and hearts,' said the Emmy-nominated TV star.

The HBO star, hailed by some as the voice of her generation, implored her fans to continue dealing with unwanted attention from trolls, stressing the importance of taking a stand against the online cowards.

Powerful presence: Lena, here with Chelsea Clinton in July at the DNC, has been hailed by some as the voice of her generation

'Please keep on swiping to delete gross comments, reporting inappropriate creeps and blocking like your life depends on it,' Dunham said. 'Because guess what? Someone's might.'

Last year, Dunham told Re/Code that she washed her hands of Twitter after she was targeted by bullies after posting a scantily-clad selfie in which she was wearing her boyfriend's underwear.

'It turned into the most rabid, disgusting comments about my body, and my Instagram page was somehow the hub for misogynists for the afternoon,' said Dunham, who said she has another person administer her account, which boasts nearly five million followers.

Fearless: The writer has been hailed for her social commentary on multiple fronts

Dunham said that while she likes the format of the site, 'it really, truly wasn’t a safe space for' her amid the torrent of cruel comments.

'I think that even if you think you can separate yourself from the verbal violence that is being directed at you, it creates some really cancerous stuff inside you,' she explained in the 2015 interview. 'Even if you think, "Oh I can read 10 mentions that say I should be stoned to death, and laugh and move on," those aren't words that should be directed at you.