IF you’ve had unprotected sex, forgotten to take your contraceptive pill or had a condom break, you’ll likely find yourself at a pharmacy the next day buying a morning after pill.
But the pill might not work for millions in the UK, as being overweight or obese could affect how effective the drug is, a women’s health expert has warned.
The morning after pill – also referred to as emergency birth control – works by delaying the release of an egg.
Sperm can stay alive in the genital tract for up to five days, but delaying ovulation with the pill means the sperm will likely die before it can fertilise an egg and result in pregnancy.
Dr Frances Yarlett, NHS GP and Medical Director at The Lowdown, told Sun Health that there could be a risk of the morning after pill being less effective if you’re overweight or obese.
She cited research published in 2011, which found that women taking levonorgestrel morning after pills were more likely to get pregnant if their body mass index (BMI) was higher than 30, compared to those whose BMI was lower than 26.
BMI measures whether you’re a healthy weight for your height.
According to the NHS, having a BMI of 25 to 29.9 means you’re in the overweight range, and one of 30 or above means you’re obese.
The 2021 Health Survey for England estimated that almost 30 per cent of adults in England were obese, while nearly 40 per cent were overweight.
“Research studies looking at different people, found that the concentration of levonorgestrel in the bloodstream was lower in people with higher BMIs,” Dr Yarlett said.
“This means it is possible that the levonorgestrel morning after pills could be less effective in people with a weight over 70kg or a BMI over 26.”
The GP noted that there are two different types of morning after pill.
Brands such as Levonelle One Step, LoviOne or Ezinelle use the progestogen hormone levonorgestrel and can be taken up to 72 hours after unprotected sex.
The other type of morning after pill is called ellaOne, and this can be used up to five days after sex.
“Frustratingly, the morning after pill is a paid for medication from pharmacies, and this may affect women’s choice of pill and prevent them from taking a higher dose,” Dr Yarlett said.
“This is why we would love to see the morning after pill free for all.”
A Lowdown blog breaking down different forms of emergency contraception adds that ellaOne may be less likely to work if you have a BMI above 30 or weigh more than 85kg.
“Doubling the dose of the levonorgestrel pill has been suggested to increase the effectiveness, but another study suggests this makes no difference,” it said.
Guidelines from the the UK Faculty of Sexual and Reproductive Healthcare suggest that ellaOne should be offered to women weighing over 70kg or with a BMI over 26, or two levonorgestrel tablets is this pill isn’t available.
The Lowdown suggests discussing your options with a pharmacist.
“It’s really important to know that neither of the types of morning after pill are effective after you have ovulated,” Dr Yarlett stressed.
“If you have already ovulated, or you cannot have a morning after pill, you can have the copper coil fitted as an emergency.”
CAN OTHER FACTORS MAKE IT LESS EFFECTIVE?
Taking certain medications may reduce the effectiveness of the morning after pill or influence which one you can take, Dr Yarlett added.
“Certain medications can reduce the effectiveness of both types of morning after pill, so you should always discuss any regular medications with a pharmacist or GP,” Dr Yarlett said.
According to Drugs.com, there are over 245 drugs that can interact with the morning after pill, ranging from minor to severe interactions.
The treatment can become less effective if you take St John’s Wort, medication for epilepsy, HIV or tuberculosis, or you’re on certain types of antibiotics.
“If you are on medications which affect the morning after pill, you can always choose the copper coil,” Dr Yarlett advised.
According to the GP, the copper coil is the most effective form of emergency contraception and everyone requesting the morning after pill should be offered the copper coil first, to be fitted within five days of ovulation.
“The copper coil can then be used long term for contraception, or removed after you have checked you are not pregnant, as it may not be your first choice of long term contraceptive,” she explained.
“Women with severe asthma that is treated with oral steroid tablets cannot have the ellaOne morning after pill.
“And women who are breastfeeding should not feed directly for one week after taking ellaOne, with the advice to “pump and dump” for seven days.”
If you’re on hormonal contraception, you can start taking it straight away after having levonorgestrel morning after pills, but you should wait for five days before re-starting contraception if you take ellaOne.
In these cases, the you should be offered the copper coil.
HOW YOUR BMI CAN AFFECT CHOICE OF CONTRACEPTIVE
Aside from making the morning after pill less effective, your BMI can also have an impact on your choice of contraceptive.
“We know that those with a higher BMI are at an increased risk of blood clots,” Dr Yarlett told Sun Health.
“As combined hormonal contraception – the pill, patch or vaginal ring – can also slightly increase the risk of blood clots, we have to consider BMI alongside other risk factors for blood clots such as smoking and family history,” she explained.
“If your BMI is over 30, your nurse, doctor or pharmacist should discuss the risks of taking combined hormonal contraception against the benefits.
“For some people – for example, if your BMI is over 35 – the risk of getting a blood clot is greater than the risk of getting pregnant, so you would be advised to choose a different method.
Read more on the Scottish Sun
“All other methods of contraception are available to people in larger bodies of any BMI – including the progestogen only pill, the coils, implant or injection.”
The GP advised using The Lowdown’s recommender or comparison tools is you’re struggling to choose which contraception to take.
A guide to taking the morning after pill
EMERGENCY contraception can stop you from getting pregnant after you’ve had unprotected sex.
This applies to when you haven’t used a condom, the condom broke or you forgot to take your contraceptive pill.
You need to use emergency contraception within three to five days of having unprotected sex. The sooner you take it, the more effective it will be.
Just like all methods of contraception, it’s not 100 per cent guaranteed that the morning after pill will protect you from pregnancy.
Depending on how much time has passed since you had unprotected sex, you might be limited on what treatments you can seek.
There are two main types of emergency pill used in the UK:
- Levonorgestrel like Levonelle, which you need to take within three days after sex
- Ulipristal acetate like ellaOne, which you need to take within five days after sex
You can also have an intrauterine device (IUD) – also known as the copper coil – fitted within five days of having sex.
It’s a small plastic T-shape that a specially trained nurse or doctor can put into your womb at a sexual health clinic or GP surgery.
You can choose to leave in the IUD as your usual method of contraception and it will last you five to 10 years, depending on the type.
How often can I take the morning after pill?
While you can take the morning after pill as often as you need to, it’s not recommended that you use it as a regular method of contraception.
There are no long-term effects on your body if you take it often, but there are other methods of contraception that are much more effective and easier to manage.
Can the pill cause side effects?
Most people who take the morning after pill won’t experience side effects.
But you might experience:
- A headache
- Stomach ache
- Changes to your periods – your period could temporarily be earlier, later, lighter, heavier or more painful
- Nausea or vomiting – if you do vomit after taking your morning after pill (within two hours for levonorgestrel or three hours for ellaOne) you will not be protected against pregnancy and will need to get a second dose
To combat nausea, you could take the morning after pill with some food to line your stomach.
Where can I get the morning after pill?
You can get the emergency pill or IUD free from:
- Most sexual health clinics
- Most GP surgeries
You can also get the emergency pill for free from:
- Some NHS walk-in centres
- Pharmacies that offer NHS emergency contraception services
- Some young people’s services (call the national sexual health helpline on 0300 123 7123 for more information)
Sources: NHS and The Lowdown