Women owe a lot to Margaret Sanger, the pioneer of women’s reproductive rights and founder of the American Birth Control League, the precursor to Planned Parenthood.
In 1951, she convinced Dr Gregory Pincus to develop the first oral contraceptive pill and run the necessary clinical trials. In 1960, the pill was officially approved by the Food and Drug Association (FDA), and from there, it quickly made its way through the Western world, landing on Australian shores in 1961.
Although until 1972, it came with a hefty 27.5% luxury tax and was only available to married ladies. Thankfully, that’s no longer the case and around 27-34% of Australian women claim the birth control pill as their go-to for contraception .
You may know that the pill is 99% effective at preventing unwanted pregnancy (when used correctly), but there is a lot more to learn about this magical little pill . So first things first, what is the contraceptive pill and how exactly does it work?
How does the birth control pill work?
The short answer is that it stops you from ovulating. If you don’t ovulate, there’s no mature egg released and simply put, no egg = no chance of getting pregnant.
Birth control pills work by synthetically keeping the levels of oestrogen and progesterone equal at all times.
This stops the pituitary gland in your brain from sending signals that release the 2 hormones that trigger ovulation: the follicle-stimulating hormone, which signals the growth and maturation of ovarian follicles, and the luteinizing hormone, which prepares a mature egg follicle to burst and release the egg.
In addition to this, the pill also helps to prevent pregnancy by changing the consistency of your cervical mucus, making it harder for sperm to get through.
What are the types of birth control pills?
There are 2 versions of the pill to choose from, and they work in different ways.
The combined pill
This is the OG birth control pill and the one that most people are referring to when they talk about “the pill”. The combined oral contraceptive pill is made using both oestrogen and progestin, which works to prevent pregnancy in 3 ways:
- It prevents ovulation. Remember, no egg, no chance of pregnancy.
- It thins the lining of your uterus, essentially making it an environment incapable of nurturing a fertilised egg (if one were to exist).
- It thickens your cervical mucus, creating a barrier between your uterus and sperm, which makes it nearly impossible for the little swimmers to pass your cervix.
The mini pill
The mini pill contains progestin only and is great for women who may not be suited to be exposed to additional oestrogen.
It’s also commonly prescribed for breastfeeding mothers as some studies have shown that oestrogen can interfere with the lactation process.
Progestin is a synthetic form of the hormone progesterone, which is produced after ovulation by the corpus luteum — the discarded follicle sac of your mature egg — in a regularly ovulating body. Its purpose is to support the development of the endometrium (uterine wall) to make it suitable to host a fertilised egg (embryo).
However, when progestin is present at high levels, it not only prevents the body from ovulating, it actually regulates the uterine wall, preventing it from getting too thick. Given a growing egg needs a thick, cushy uterine wall to grow in, there are no chances of implantation here.
The other thing to note is that the mini pill consists of only active pills, meaning there are no placebo or inactive pills in the pack. As such, there will generally be an absence of the actual period, though the lack of oestrogen can allow for some breakthrough bleeding to occur, especially if you miss a pill, even by a few hours.
Kin's pill subscription makes getting birth control pills delivered on time easy. A Kin membership includes free and fast delivery of your contraception to your door two weeks before you run out (or earlier if you prefer). And, this means no more trips to the doctors or chemist — simply complete a digital consult with our Aussie practitioners and you'll have your pill in no time.
Does the pill make you skip your period?
One of the major draw-cards of taking birth control is the ability to forego that monthly ritual of letting it flow — but is it safe to skip your period?
In short, yes. But the truth is, it really depends on your individual body.
There are heaps of reasons you may want to skip your period, which can range from serious medical conditions like endometriosis and dysmenorrhea to more practical reasons, like the beach holiday you’ve planned.
For many women, like active-duty military, who work in environments with limited access to clean bathrooms, the ability to control menstruation at work is not just convenient, it’s often necessary.
Plus, severe menstrual symptoms like excruciating pain caused by endometriosis, intense mood disorders caused by premenstrual dysphoric disorder (PMDD), and menstrual migraines don’t get activated when you skip your period, so the benefits of the pill can reach far beyond convenience.
Benefits of the pill for women with PCOS and endometriosis
There are some major benefits to taking the pill, particularly for women who suffer from endometriosis or polycystic ovarian syndrome (PCOS), which is estimated to be around 10% of women .
While it’s not exactly clear what causes these issues, they’re categorised by unbearable pelvic pain, irregular cycles, and things like acne or hair in unusual places. So knowing there is some relief is, well, a relief.
Endometriosis is the overproduction of the uterine lining, which causes it to grow on other areas of the body, such as the ovaries, bowel, rectum, bladder, and around the pelvis. PCOS is the growth of numerous small or large cysts along the outer edge of the ovaries.
The pill regulates hormone levels in the body and stops the uterine wall from building up excessively (which is called endometrial hyperplasia), while also preventing the development of ovarian cysts, essentially keeping these 2 at bay.
While the pill has been shown to improve common symptoms of hormonal imbalances, it shouldn’t be considered a one-size-fits-all solution. As always, it will depend on your individual body and needs and it’s always best to discuss your options with your doctor.
Kin's pill subscription includes unlimited consults with an Australian practitioner and you can chat with our experienced GPs about anything related to your contraception — whether it be about periods, side effects or changing prescriptions.
Does anything make the pill less effective?
Yeah, she’s tough, but there are still a few watch-outs when it comes to the effectiveness of your pill.
Some medications can reduce the pill’s effectiveness by increasing the metabolisation of hormones.
Specifically, one study showed that consistent use of antibiotics such as rifampicin and rifabutin, drugs used to treat tuberculosis and meningitis, and a selection of anticonvulsants can prevent the pill from suppressing ovulation .
These drugs increase enzymes in your body, which can interfere with the processes of oral contraception. Others include :
- Anti-fungal drugs
- Certain drugs used to prevent seizures
- HIV medications
Even though there is limited research on the interference of these medications with birth control, it’s best to exercise caution if you’re taking anything that may put you at risk. Use a backup method of birth control throughout the course of your treatment and for at least 1 week after.
Most supplements have no effect on contraception, but a select few herbs, extracts, and other natural supplements can make it less effective by decreasing absorption or interfering with the breakdown of the hormones.
The supplements listed below have raised concerns about causing interference with the pill. If you’re taking any of these or additional herbal supplements, be sure to read the packaging carefully, speak to your pharmacist about the potential impact, and always use a backup form of contraception if you’re unsure.
- Flaxseed 
- Saw Palmetto 
- Garlic pills 
- Alfalfa 
- St. John's Wort 
All of these supplements are best avoided if you use the pill as your only form of birth control. If you accidentally take any of the supplements listed above, it’s best to use condoms or another secondary form of birth control to reduce your risk of pregnancy.
Your body needs to fully absorb each and every birth control pill you take in order to stop you from becoming pregnant. If you have a digestive or autoimmune disorder like Crohn’s disease, Coeliac disease, or IBS, it could make the pill less effective.
Temporary digestive issues such as vomiting or diarrhoea also have the potential to make the pill less effective, so it’s important to use a second form of birth control, such as condoms if you experience acute diarrhoea that lasts for longer than 24 hours at a time.
A healthy BMI range in Australia is considered to be anything between 18.5-24.9. If your BMI places you in the overweight or obese range, you have a higher risk of becoming pregnant while using contraception than women who have a lower BMI.
Researchers have actually found that women with a BMI of 27.3 or higher had a 60% higher risk of becoming pregnant while using the birth control pill than women with a BMI that ranked in the mildly overweight category or lower .
Plus, women with a BMI higher than 32.2 have a more than 100% higher risk of becoming pregnant while using contraception.
In general, the effectiveness of contraception decreases as your weight and BMI increase.
What to do if you miss a pill
It’s important to take your pill at the same time every day for the best results and effectiveness. Its effectiveness drops to about 91% when factoring in human error, like missed pills or inconsistency in the time of day you take the pill, meaning it's still possible for you to get pregnant .
But life gets in the way.
If you miss a pill, take it as soon as possible (even if this means taking 2 pills on the same day). If you miss more than 1 pill, take the missed pill as soon as you remember but ensure you’re using a backup form of contraception until you’ve taken 7 hormone pills in a row. You may also want to consider getting your hands on the morning after pill.
Always refer to the instructions on the packaging of your specific pill to ensure you’re following the best procedure and are protected.
Oh, and another quick note: if you miss a sugar pill, there’s no need for concern.
In fact, some packs don’t even have sugar pills. Sugar pills contain no hormones and serve the purpose of only keeping you in the habit of taking the daily pill so that you stay on track when it comes time to start a new hormonal pill pack.
What if you miss a mini pill?
Then, the above advice doesn't apply. If you’re taking the mini pill, your contraception has lower levels of hormones, meaning if you miss it by even 3 hours it may reduce the effectiveness .
It’s absolutely necessary to use a backup form of contraception for at least 2 days if you miss 1 of your mini pills.
Common side effects of the pill
There is a range of potential contraceptive pill side effects. The good news is, for the most part, they aren’t incredibly serious and should subside after your body adjusts, usually within a month.
Some women experience breakthrough bleeding during their cycle if they choose low-dose pills or mini pills. Similar to what happens when taking the sugar pills in your pack, the lower dosage or lack of oestrogen can trigger the body to release the uterine wall and cause spotting.
Perhaps one of the most common concerns when making the decision to go on the pill is weight gain.
It’s not unheard of to put on weight during your period and lose it just as quickly, but there's actually no link between weight gain and oral contraceptives .
What there is, however, is a link between increased levels of oestrogen and fluid retention .
Medically, this is known as premenstrual fluid retention and it occurs naturally in your cycle as hormones fluctuate and oestrogen and progesterone levels rise. Combined oral contraceptive pills can cause oestrogen levels to be anywhere from 6-10 times higher than normal, so naturally, fluid retention can be triggered.
If you notice a rapid increase on the scale within the first few weeks of taking the pill, without any major changes to diet and exercise, it’s most likely fluid. As you maintain your normal health habits, you’ll notice your body will adjust and you’ll gradually make your way back toward the norm.
Again, similarly to what happens naturally during your cycle when your hormone levels increase, the pill can stimulate breast tissue, resulting in anything from mild discomfort to enlarged breasts.
While the pill can cause benign lumps to occur in your breasts, studies have shown a decrease in hospitalisation for the treatment of these non-cancerous growths among women who take the pill .
However, know your boobs, ladies! Keep tabs on anything that feels out of the ordinary and when in doubt, see your doctor.
While it may occur when you first start taking the pill, nausea is more commonly a result of emergency contraceptive use than regular birth control.
Lower sex drive
The pill reduces the levels of androgens in your system, so it can lower your sex drive, with about 15% of women reporting changes to their libido .
Testosterone is the major androgen associated with sexual urges, and your body naturally increases its production during ovulation to encourage frisky business at prime fertilisation time.
We’re not only not ovulating when taking the pill, but the increased levels of female sex hormones hinder the production of testosterone . You get the picture.
Less common, more serious side effects
There are some less common, albeit more serious, side effects involved with the pill. Similarly to the above, the majority should subside. However, if any of these symptoms persist or really strike you as out of the ordinary, speak to your doctor ASAP.
Headaches and migraines
Increased risk of headaches and migraines is more common in users of combination pills, so if you’re already susceptible, choosing the mini pill or a lower dose combined pill may be best.
Migraine headaches affect 24% of women of reproductive age and can be completely debilitating . They can last from hours to days, are characterised by severe pain and throbbing, and can be accompanied by nausea, vomiting, and extreme sensitivity to light.
If you begin suffering migraines after starting birth control, speak to your doctor immediately as it may signal an increased risk of stroke and it’s best to seek an alternative contraceptive option.
Truthfully, the links between oral contraceptives and mood changes are understudied.
However, one particularly oft-cited study in Denmark has shown links between increased hormone levels (particularly progesterone) and depression. This is also why during a normal cycle you experience symptoms of PMS when progesterone levels are on the rise .
Keeping in mind that your levels are elevated continuously whilst using contraceptives, there is a slightly higher chance to experience feelings of depression, anxiety or fear, with about 4-10% of women reporting negative changes to their mood .
While some studies show a link between breast cancer and birth control pills, they also show that risk increases slightly in women who use the pill for more than 5 years. However, the risk is ultimately small, increasing from about 1 time higher to 1.6 times higher .
That said, thanks to the pill’s regulation of the development of the uterine wall, taking the pill has actually shown a 50% reduction in the risk of endometrial cancers, a reduced risk of developing ovarian cancer, and an almost complete cessation in the development of ovarian cysts . That’s pretty fab news.
Blood clots and deep vein thrombosis (DVT)
The FDA has reviewed a selection of studies identifying an increased risk of developing blood clots, including DVT, in women taking birth control pills containing progestin. The FDA found the risk at about 3-5 times higher than the average healthy, non-pregnant, non-birth-control-taking woman .
For new mothers particularly, using combination birth control pills is not recommended within 3 weeks of delivery, as your risk of DVT is heightened immediately after childbirth.
While oestrogen has been linked to an increase in blood clots, the risk is actually considerably low assuming you’re not predisposed to their development. If you are, it’s extremely important to have a conversation with your doctor about the best possible contraceptive solution for you.
You may be predisposed to blood clots if you’ve had surgery, trauma to the body or brain, pregnancy, hormonal therapy or are immobile.
Blood clots can also be genetic, so getting a good grasp of your family health history is important. If you have previously had any blood clots, or are aware of any family history of blood clots, it’s extremely important this is brought up with your doctor. It may not be appropriate for you to be on the combined pill and alternative options should be discussed.
Does the pill decrease fertility?
This is a big one as there is a lot of speculation around the fertility rates of long-time hormonal birth control users. In short, years of taking the pill won’t affect your long-term fertility in itself.
In fact, a study out of UPenn showed 81% of subjects achieved pregnancy within a year of stopping the pill .
In some women, their menstrual cycle may take some time to return to normal after stopping the pill . If your cycle hasn’t returned after 3 months, speak with your doctor.
However, there is a number of other factors that can affect your fertility rates such as iron levels, thyroid health, age, and lifestyle, so even while you’re adamantly preventing pregnancy in your early years, be sure you’re staying on top of your overall fertility knowledge if you do want kids one day.
Understanding your fertility ensures that you protect your options in the future. By taking a fertility test now, you can proactively identify any reproductive health issues early and make informed decisions about your fertility journey.
Kin's Fertility Hormone Test is a simple blood test followed by an online GP consult that provides you with personalised insights about your ovarian reserve, possible egg freezing and IVF outcomes, possible signs of PCOS as well as your menopause timing, reproductive timeline, and more.
Ongoing support is available, such as through our free fertility planning tools or by connecting with our qualified Australian practitioners.
That’s a whole lot of information, but all up, it’s super important to know the facts before you jump in, and that goes for just about anything.
All bodies are completely unique and there is no one-size-fits-all solution. Assess what’s most important to you in terms of your contraceptive choices and speak to your doctor or get in touch with one of our Kin practitioners. We can help you make a choice that’s right for you.