What’s the biggest myth about periods?

That the menstrual cycle repeats itself regularly every 28 days. This is the average length, but there’s a huge healthy range, from 21 to 40 days, and the length typically varies by two to four days each time. It’s a problem because people whose periods don’t fit into a 28-day pattern can feel like there’s something wrong.


Why do some people get such heavy periods?

Average menstrual blood loss is about 30ml to 45ml, or two to three tablespoons per period, but again there’s a range. Technically, anything over 80ml is considered heavy. It’s thought there is a genetic component. Annoyingly, anaemia can also trigger heavier periods, creating a vicious cycle!

Is it a good idea to track periods with an app?

I think everybody should track their cycle for a while to see what’s normal for them. If you have symptoms, it can help your GP to determine if they are related to your cycle or not, and spot signs of other problems. It’s worth saying that cycle tracking alone is not an effective form of contraception!

Need to know...

  1. Don’t worry if your cycle is not 28 days. This is only the average.
  2. There’s no need to take a break from the pill if you’re happy with it and doing well.
  3. Ibuprofen not only helps with pain of cramps, it can also reduce blood flow.

What things does my menstrual cycle affect that I might not realise?

Many chronic health conditions can be triggered or worsened at certain points in the cycle, including migraine, epilepsy, allergies and food intolerances. Asthmatics may find they are wheezier at certain times in their cycle. These connections are well established in clinical research, but they haven’t yet passed into clinical advice for patients.

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What’s the best way to deal with period pain?

Anti-inflammatories, like ibuprofen, really help. Not many people realise this, but the time to start taking ibuprofen is two to four days before you expect to start your period.

If you do this, it not only reduces cramping, it also reduces the amount of blood you lose. This can make a big difference for people with painful, heavy periods. Magnesium supplements can help, as can more traditional approaches like exercise and hot water bottles.

© Sofie Lee
© Sofie Lee

Is it okay to take pill packets back to back to avoid a period?

Yes. It may not always prevent bleeding, but it will reduce it. There’s this idea that if you don’t have a regular bleed that you’re somehow accumulating toxins or hormones. This isn’t true. The lining of the womb just doesn’t build up as much in the first place.

Is it a good idea to take a break from the pill?

If you’re on the pill and doing well, there’s no reason to have a health break. Some people worry that the pill can damage future fertility, but this isn’t true. It can take time to get pregnant after coming off the pill but most people regain their natural cycle after three to four months.

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Helen Pilcher
Helen PilcherScience writer, presenter and performer.

Helen Pilcher is a tea-drinking, biscuit-nibbling science and comedy writer, with a PhD in cell biology.