How effective is the contraceptive pill?

Things that can increase pill failure and how to protect yourself from pregnancy


Things that can Increase Pill Failure and how to Protect yourself from Pregnancy

Out of the plethora of birth control options available today, for many women, pills are the go-to method because they are a fast, easy, convenient, and non-invasive way to prevent pregnancy if taken correctly.

The way the pill works to safeguard a woman from pregnancy depends on the type she takes – the combined pill (containing estrogen and progesterone) or the mini pill (containing progesterone only).  The former stops ovulation by preventing the ovaries from releasing an egg each month, while the latter thickens the cervical mucus and thins out the uterus lining, making it difficult for sperm to fertilize an egg.

The combined pill has to be taken around the same time every day for 3 weeks, followed by a 7-day break, in which you should experience a period-type bleed. On the other hand, the mini-pill must be taken consistently every day; once you start, do not take any breaks in between packs, and make sure that you ingest the pill within the same 3-hour window each day to achieve maximum efficacy.  

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Can I get pregnant while taking the pill?

In an ideal world, a woman will use the pill perfectly – that is, on a consistent basis for the prescribed period, without missing any days in between. Based on this assumption, the pill is over 99% effective, meaning that only 1 out of 100 women will likely fall pregnant in a year. This statistic may make the pill sound like a fool-proof way of preventing pregnancy but, unfortunately, this world is far from perfect; with all of the complexities and distractions we face on a daily basis, not all of us will remember to take the pill at the same time every day, without fail. This is where its efficacy somewhat declines to around 91%. In other words, around 9 out of 100 women are likely to fall pregnant with typical use of the pill.


What reduces the effectiveness of birth control pills?

Contraceptive pills are considered lifesavers for many women leading busy lives who need an efficient yet effective method of birth control. But despite its usefulness, there’s a particular protocol you must follow in order to save yourself from the risk of a real sticky situation.


Not taking the pill as instructed

As discussed above, when it comes to the pill doing its job properly, timing (and consistency) is everything. Missing a day, or not taking it at the scheduled point, can result in hormone levels not being at the required level to protect against unwanted pregnancy. This rule is especially important if you’re taking the mini pill as its effects usually begin to deplete after 27 hours, which means you must ensure that you take it within the same 3-hour window each day. If for whatever reason, you miss 2 or more pills in a row, you must use a backup form of contraception until you’ve taken the pill for 7 consecutive days.


Vomiting or diarrhoea

Falling ill can be a nuisance at the best of times and the stress of having to take the pill while vomiting or having severe diarrhoea can make matters even worse. If you threw up within 2 hours of taking the pill or have had ongoing episodes of diarrhoea, it is highly likely that your body did not fully absorb the medication, which would increase your risk of getting pregnant. If this happens to you, take another pill straight away to make sure you’re protected. If your illness lasts for more than 24 hours, you may want to think about using added contraception, such as condoms, until you get better.


Other medications that interfere with the pill

Certain medications, as well as herbal remedies and supplements, may reduce the efficacy of your birth control. So you may want to have a quick rummage through your medicine cabinet to make sure there aren’t any sneaky suspects hiding in plain sight. Antibiotic and antifungal drugs, more specifically Rifampin and Griseofulvin, may render the pill ineffective, as well as certain HIV and anti-seizure medicines. Even natural, herbal remedies like St. John’s Wort and high doses of vitamin C have been known to interfere with birth control pills, so you may want to steer clear of these while using this contraceptive method. If any of these medications are unavoidable and you’re likely to be on them for a long period, speak with your doctor about switching to an alternative form of birth control.


What can I do to prevent pill failure?

By failing to prepare, you are preparing to fail – this is especially relevant when taking birth control pills. Being organized and following a precise routine can help to prevent any unintended pregnancies. The following tips can assist in making sure that your pills work as intended and avoiding any unwanted surprises weeks down the line:

  • Always keep another form of birth control at hand, such as condoms or spermicide, just in case you forget to take your scheduled dose of the pill - after all, you can never be too careful.
  • If you’re planning on spending nights away from home, make sure you pack your pills with you.
  • Take your pill at the same time every day. If you’re having trouble remembering to take your pill, try setting daily reminders on your phone or download a period tracking app that will alert you when it is time for your next dose.
  • Better still, you could explore long-acting, reliable alternatives that don’t require you to do anything on a regular basis to maintain their contraceptive efficacy. Viable options include an intrauterine device (IUD) or an arm implant; speak with your doctor for more information or if you would like to have either one inserted.
  • Always take a missed pill as soon as you remember and use a backup method of birth control if you miss 2 consecutive doses.
  • Don’t leave your prescription to the last minute. Make sure you get your new pack of pills at least 1 week before your current one is due to run out to avoid any unforeseen difficulties.
  • If you ever fall ill and need to visit your doctor, tell them you’re on the pill to make sure that any medication they prescribe you doesn’t interfere with your birth control. 

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