In 1961, the contraceptive pill first came out in Australia. It was a huge deal. Massive. For the first time, women had control over their sexual and reproductive health. We had options and a sense of freedom that we had never experienced before.

We entered the workforce. We extended our education. We got degrees. We made money. The introduction of oral contraception was revolutionary.

It had a powerful impact on social and economic benefits for women, and has been hailed as one of the greatest scientific innovations of the 20th century.

Watch: Did you know there are different types of birth control pills? Here's some advice on how to find which one is right for you. Post continues below.

These days, around 922 million women of reproductive age (or their partners) are contraceptive users.

When taken correctly, the pill is more than 99 per cent effective at preventing pregnancy, and many women who take it enjoy positive side effects such as clearer skin, fewer PMS symptoms, regular periods and improved moods.

However, while we can't forget how groundbreaking it was or what it did for women, the pill isn't perfect. In fact, we're only now beginning to learn that it's far from it.

While we usually focus on the physical side effects of the pill, you might not be aware that the most common reason women stop taking the pill is not because they're ready to start a family — but due to mental health issues.

There are women who experience little to no negative side effects taking the pill, but there are also many more who report things like a serious loss of libido, depression, anxiety and even suicidal thoughts.

To put this into perspective, these side effects are coming from one of the most commonly prescribed forms of contraception in Australia. Something that one in four Australian women between the ages of 18 and 49 use.

Pretty scary, huh?

But it's not completely surprising. For a long time we've been aware of how the pill can make us feel sad, angry, or just a bit 'off' — ask any woman and if she hasn't experienced some negative side effects, chances are she'll know of someone who has. The problem is, no one has been told why.

While some of these people will decide to go off the pill, many of us will stay on it — or not even be acutely aware of these side effects. So more often than not, these issues just get pushed into the back corner.

But did you know there's actually a proven link between the pill and poor mental health? A big fat link that no one really talks about? We didn't. In fact, we had to write an entire article on it before we found out how the pill impacts our brain.

In recent years new studies have not only verified this link, but revealed so many other side effects most of us are completely unaware of. Negative and potentially long-term effects of something healthy women, like you and I, take every day.

That's pretty terrifying.

So, why are we tiptoeing around the suggestion the birth control pill could be problematic? Why is it so explosive if we're talking about our health?

Well, it's an incredibly delicate subject for good reason. The stakes aren't just high for anyone who has ovaries, but the possibility of scaremongering and unwanted pregnancies is a very real risk.

So now we've found ourselves trapped in this weird limbo where we don't want to be ungrateful, but we know we deserve better.

Let's break down what we know.

Does the pill really cause depression and anxiety?

Okay. We're not going to dance around it — the research behind this paints a pretty bleak picture.

Professor and author of This Is Your Brain On Birth Control, Sarah Hill, wrote an entire book that validates what generations of women have suspected since the introduction of the pill — that it is doing a whole lot more than simply preventing pregnancy.

She told us that oral contraceptives are affecting women’s thinking, emotions and behaviour. And we need to have a conversation about it.

"There has been a growing body of research that suggests that women who are on hormonal contraception are at greater risk of developing depression and anxiety than women who are not," said Professor Hill. "Research suggests that these differences stem from differences in hormonal and neurotransmitter activity in the brains of hormonal contraception."

In Australia, Jayashri Kulkarni, a Professor of Psychiatry at Monash University, led research into the effects of oral contraception on mood and anxiety. Her study found that woman taking the oral contraceptive pill were more likely to be depressed than non-pill users.

It was discovered that women taking the pills with low amounts of oestrogen had more depression than those taking higher oestrogen dose pills. (FYI: Typically, combined oral contraceptive pills contain a form of estrogen and a form of progesterone).

Overall, the study found that the progesterone-only contraceptives were the most depressive of all the contraceptives.

Further to this, a 2016 study conducted in Denmark by Professor Øjvind Lidegaard, showed women taking the combined oral contraceptive pill were 23 per cent more likely to be diagnosed with depression, while those using progestin-only pills were 34 per cent more likely.

In an interview with Refinery29,Lidegaard explained that while we know some women experience severe mental health side effects when taking hormonal contraception — the problem was that beyond his study we don’t know exactly how many are affected. Professor Lidegaard and his team were only able to run this study because Denmark collects patient and prescription data.

"There has been a lot of research in hormonal contraception," he told Refinery29. "On mental health, the quality of the studies have been poor and the results consequently unreliable. Those studies, for example, had not followed women from their first use of hormonal contraception in the way we did."

Since Professor Lidegaard's research, a study was conducted in late 2019. It was led by Dr Michael Lipton, Professor of Radiology at the Albert Einstein College of Medicine in New York, and it found that hormonal contraception might be "altering the structure of women’s brains".

It was noted that the pill had an effect on a part of the brain (called the hypothalamus) which regulates pretty much all of our hormones. However, it was concluded that further investigation is needed into how hormonal contraception potentially impacts a woman's brain function.

Yet, despite the significance of these studies and the overwhelming evidence produced, it is surprising that nothing has really changed.

"This is something that has been found in research studies since the 1990s. It's crazy to me that a bigger deal hasn't been made of this," said Professor Hill.

So, why hasn't there been more noise made around these studies? Why are we all being left in the dark?

Well, the fact is that until very recently, there has been little research surrounding hormonal contraceptions and mental health. And the research that is out there isn’t being published in medical journals, but rather in psychology and neuroscience journals. Meaning? Doctors often aren’t aware of these side effects.

Professor Kulkarni, who led the Australian study, also said it's still a taboo topic in society.

"While the data shows a link between certain types of pill (eg: progesterone-only pills, subcutaneous and intra-uterine devices — are associated with higher levels of depression), there is still confusion because many women using hormone contraception do NOT experience depression. Their experience throws doubt on the experience of those who do."

Professor Kulkarni also says that often the type of depression experienced on the pill is not always the easily recognised major depressive disorder with characterised, described symptoms. "I also think there is reluctance to believe that gonadal hormones impact mental health – although there is ample neuroscientific evidence for this," she adds.

According to Professor Hill, more research and medical intervention is the only way forward.

"The stress response of pill-takers looks very similar to that of people who have PTSD or have experienced trauma. This is also something that is linked with depression and anxiety. There isn't a clear answer, yet, for why this happens and there is critical need for new research on this," she explains.

When we spoke to Associate Professor Caroline Gurvich, Clinical Neuropsychologist and Deputy Director of Monash Alfred Psychiatry research centre, she said there is a crucial need to learn more about which women are vulnerable to the adverse mood effects.

"Research suggests somewhere between 32 per cent and 60 per cent of women discontinue oral contraceptive use within six months for a variety of reasons — but one of those reasons is mood changes."

As 22-year-old Melinda tell us: "I tried four different versions of the pill across a year and a bit, and my god it was chaotic. I was extremely moody and on edge. I was constantly eating and my head always felt a mess, to the point my boyfriend was concerned for my health. It also triggered my anxiety and depression. I already had this but the pill just amplified it and I ended up needing to see a doctor. Never again."

While the statistics speak for themselves, for some reason it is still surprising and scary to find out how common it is for Australian women to experience a wealth of side effects on their mental health.

After being on the pill for nine years due to polycystic ovary syndrome, 24-year-old Emily recently went off it only to experience dramatic changes in her body and mental heath.

She said, "I suffer from sporadic depression episodes and I haven’t had one since. My scalp has gotten so much oiler, my skin, which used to be oily is now dry.

"I lost 2kg the minute I got off it, I eat heaps less, my mood is so much brighter and I feel like I’m in control with my feelings."

One 26-year-old woman said, "I have been on the pill for 11 years, and one time the doctor messed up one of my scripts and gave me a different dosage (I went from Microgynon 25 to Microgynon 30) and I literally slipped into a black hole. I felt like everything was hazy and I cried pretty much for two weeks straight. It was terrifying. I realised then that the dosage was different and switched back ASAP."

These studies and experiences not only verify very obvious links to poor mental health, but they also highlight the need for more research into the negative and potential long-term effects of the oral contraception pill.

"Learning more about why some women are particularly vulnerable to adverse mood effects is needed. Developing a biomarker (e.g. a marker that could be picked up in a blood test) that could identify which women are vulnerable to adverse mood effects would be a significant step forward," said Gurvich.

However, this need for further research then ties us into another issue — the funding of clinical trials. It's obviously very expensive to secure research funding, and the main sponsors are often drug companies — which makes things incredibly difficult when you're trying to prove the negative effects of a medication.

What other side effects have been associated with the pill?

Yep. There's more. Beyond the link between depression and anxiety, Professor Hill said there are other, lesser-known side effects you might not be aware of. The fact is that sex hormones have a domino effect on other parts of our body — the pill doesn't just affect your ovaries.

Listen: More of a podcast person? That's cool. Here's what no one tells you about the pill and men. Post continues below.

"In addition to impacting mood and the stress response, hormonal contraceptions can impact sexual functioning and who we are attracted to, the way our brain processes rewards, the structure of the hippocampus and hypothalamus, how hungry we feel, our ability to persevere on difficult tasks, and certain aspects of our memories," said Hill. "The effects are pervasive because there are sex hormone receptors on cells in almost all key areas of the brain."

Just on the fact that pill can alterWHO YOU ARE ATTRACTED TO: Apparently oestrogen is known to shape a woman's preferences when it comes to partners. The hormone steers us to favour qualities associated with masculinity and higher testosterone, like square jaws and broad shoulders, for example.

But research suggests women who are taking the pill are lacking this cyclical oestrogen urge (thanks to the artificial progesterone dominance), meaning their preferences towards who they are attracted to are different.

Why is this important? Well, it could lead to dissatisfaction. If a woman chooses her partner when she's on the pill and then goes off it, she may no longer find that she is attracted to the person.

When it comes to sexual functioning, for many years it has been suspected that the o