“I don’t actually talk about abortion that much, usually,” begins American comedian and actor Jenny Slate when we meet. But it would be understandable if most people thought that was all she talked about, because she has, somewhat unexpectedly for her, become the poster child for the pro-choice movement in the US. Slate is the star of the independent film Obvious Child, which has been hugely feted since its release in the States and, somewhat less pleasingly for all those involved in the movie, been dubbed by the US media as “the abortion romcom.”

“Ugh, that is such a bummer, that term. An abortion romcom – that’s not a thing!” Slate says with an eye-roll. “The movie isn’t saying that abortions are funny. It’s saying that people are funny.”

And the people in the movie – especially Slate, who plays the film’s protagonist, Donna – are very funny. Written and directed by Gillian Robespierre, Obvious Child tells the story of Donna, a standup comedian in Brooklyn whose chaotic life is a source of bemusement to her parents, who are unable to believe that their twentysomething daughter doesn’t even know how to do her taxes (“Nobody knows how to do their taxes!” Donna retorts, not wholly incorrectly.) After a painful breakup, she has a one-night stand and, while she remembers there was a condom in the bedroom at the time, “I can’t actually remember what it did.” And so, having played “Russian roulette with her vagina”, as her best friend puts it, Donna realises that she is pregnant and decides to have an abortion, and the film is about what happens after she makes that decision.

It is a testament to how conservative the US entertainment industry has become about abortion in the past quarter-century that Obvious Child has been greeted with such adulatory relief by pro-choice audiences. While Donna knows from the start that she’s going to have an abortion, the film does make something of a song and dance about it, and there’s even a shot of Donna on the hospital gurney with tears running down her cheeks. Does Slate think the subject is too controversial in the US now for it to be simply part of a film – as it was in Dirty Dancing and Fast Times at Ridgemont High back in the 80s – as opposed to a whole film?

“I don’t think so, because I don’t put a stigma on abortion,” she says, and then pauses. “I feel I have to be totally cemented in my position, all: ‘You can’t tell me what to do with my body’, but there is another part of me that is, you know, myself: vulnerable, with lots of doubts. I think our film shows that complexity.”

Facebook Twitter Pinterest Slate in Obvious Child. Photograph:Rex

With its Brooklyn setting and cast of hapless twentysomethings who talk crudely and amusingly about body functions and sex, Obvious Child has inevitably been compared to Girls, and the film and TV show share a similar flavour. Ultimately, the appeal of both is that they are clever, funny and, perhaps most importantly, female-centric.

“The way comedy is now,” says Slate, “at least in the States, there’s a lot of really big, broad stories that are acted by people but don’t really have any recognisable humans in them – and that is double for the roles that are given to women. People want to see comedies where characters aren’t sacrificed for the jokes.” One of the many reasons she loved making Obvious Child, she says, which was written, produced and directed by women and in which she co-stars with Gaby Hoffmann, “is because it really felt like a sisterhood”.

Slate has none of the self-consciously performative quality that is so common among standup comedians, even off-stage. Instead, she is thoughtful and softly spoken, with a slightly girlish voice, and she moves easily between therapy jargon and joyful swearing. She was, in fact, fired five years ago after one season on Saturday Night Live after accidentally swearing in her debut appearance when she was 27. At the time, she felt so humiliated that she became stricken with stage fright.

“I lost all of my confidence because I messed up. I’m the kind of person who likes to get As in everything, so I wasn’t kind to myself,” she says quietly.

To help snap her out of her funk, her boyfriend (and now husband) Dean Fleischer-Camp, suggested that the two of them work on an animated film together. The result was Marcel the Shell with Shoes On, a deliciously funny short film voiced by Slate, about life as a very small shell. To Slate and Fleischer-Camp’s amazement, the film went viral and, to date, has had nearly 24m views on YouTube, sparked a sequel, a bestselling book and a follow-up book coming out this autumn.

“Marcel was a totally new character who expresses self-love, and that was really important for me to express that, even though I could only do it as a tiny shell, because, back then, I was just being so hard on myself, and not in a constructive way,” she says. Today, now with the success of Marcel the Shell and Obvious Child behind, she says her feelings about the SNL debacle are: “I don’t give a shit. Not a SHIT!”

Ever since she was a child, growing up the middle daughter in Massachusetts with a potter and a poet for parents (“My parents didn’t care what we did, as long as we weren’t assholes”), she wanted to be an actor, and she only got into standup as a way to “have a voice and start a career that’s not based on insecurity or lies”. Aside from her excellent performance in Obvious Child, she’s had roles on some of the smartest US comedies of the past decade, such as Parks and Recreation, Bored to Death and Kroll Show. But, like many women before her, Slate has realised that it’s not always easy to find decent roles: “I’m pretty much done with playing a traditional bitch. There are a lot of men writing bitchy roles for women and that’s really, really simple, but if there’s not a way I can do that originally, I’m not going to do it anymore,” she says.

Facebook Twitter Pinterest Slate with Kristen Wiig in Saturday Night Live. Photograph: NBC/Getty

Slate resists concluding that women write better roles for women – “That seems to be a strange limitation” – but is not shy about pointing out gender biases. She suggests that the reason the US media flipped out about her swearing on SNL is because she’s a woman: “No one’s asking Norm MacDonald about it,” she says, referring to another SNL-er who also accidentally swore on live TV. “But because I’m a feminine woman, the media is like, ‘Oh my God, this little woman said fuck!’”

Donna has a lovely line in the film about how, as a little girl, she would fantasise about what it would be like to be a woman, “with a bra, and a blouse ... talking on my car phone to Susan ...” This actually came from Slate’s own act, and life. The reason she wanted to be an actor as a child is because she idolised women like Rosalind Russell and Carol Burnett because “they had personalities, they had a sense of style, they had a really developed sexuality that couldn’t be replaced by anyone else. That was very exciting to me. I couldn’t wait to be an adult woman and I’m glad I felt that way as a kid, because when I grew up I realised I live in a world where the female form is really disrespected, and society is often trying to wrestle the female form into a shape that looks more like a young boy.”

But as a self-professed perfectionist young woman, who went to private school and then on to a highly pressured university (Columbia), how did she avoid the kind of self-loathing that is so common among her demographic?

“I don’t think I avoided it, I think I just didn’t want it,” she replies. “I have an appetite for being happy and being sunny, which is not to say I’m immune to insecurities.”

One of my favourite of Donna’s schticks in Obvious Child is the one about how much she resembles Anne Frank and, unsurprisingly, this line also comes from Slate. “I do feel that I look traditionally Jewish, and it’s something I’m proud of and it’s something I’m a little bit insecure about, because I think maybe people don’t see me as myself. You know, that’s not the main girl, that’s the friend,” she says. “But you know, I’ve realised that’s my issue. I’m glad that I look like myself and I didn’t get a nose job to fit in, and now I’m starring in this movie and people seem to like it. So fuck it.”

• Comments have been reopened to time with this film’s Australian release