Concerning news about a contraceptive pill you might be using.

So you have sex. Maybe the condom breaks. Maybe you don’t use one. Or maybe you just forgot to take your contraceptive pill that morning.

At some point in their lives, most women will be in need of the morning-after pill.

And if and when that time comes, it would be nice to know that the pill you take will do that job it’s intended to. Right?

Well, news from Europe today kind of puts that theory into doubt.

The manufacturers of a morning-after pill have revealed that the drug might not work as effectively as it should for women with a high BMI.

Apparently HRA Pharma, the company who make the European drug, Norlevo, are going to update the pill’s packaging to indicate that it is less effective for women who weigh over 165 pounds (which is around 75 kilograms) and that it loses its efficiency altogether when taken by women over 176 pounds (which is approximately 80 kilograms).

Cue panic around the world.

Jezebel reported this morning:

As first reported by Mother Jones, HRA Pharma was originally prompted to look into the effectiveness of their emergency contraception by a 2011 study out of the University of Edinburgh, Scotland that found that “the risk of pregnancy was more than threefold greater for obese women compared with women with normal body mass index, whichever EC [Emergency Contraception] was taken.” They also found that the risk of pregnancy was particularly high if that emergency contraception was made of levonorgestrel, the hormone found in many of the major over-the-counter morning after pills sold in the United States, like Plan B One-Step. The study recommended that overweight women use IUDs.

When Mamamia read the story earlier today, the first thing we wanted to know was how this affects us in Australia.

Because morning-after pills containing levonorgestrel are sold here. And 75 kilograms? That kind of sounds like an average woman.

An indeed it is.

According to the ABS, the average Australian woman weighs around 71.1 kilograms. And 71.1 kilograms, if you haven’t already realised, is just a few kilos shy of the danger weight where emergency contraception reportedly starts to fail.

When Mamamia looked closely at the most recent data from the ABS,  we saw that between 28.2 per cent of Australian woman aged 25-34 weigh 75 kilograms or more, and that 21.8 per cent of women in the same age bracket weigh more than 80 kilograms.

Mamamia also found that 36.1 per cent of women aged 35-44 weighed 75 kilograms or more, and that 28.8 per cent of women in that same age category weighed over 80 kilograms.

So, by our calculations, that’s several thousands of women who could potentially be affected.

The question now is whether there is legitimate cause for concern.

Mamamia spoke to Philip Goldstone, the Medical Director at Marie Stopes about the European findings.  Here’s what he had to say:

In Australia, we only have one emergency contraception pill on the market, which does include the active ingredient levonorgestrel. There have been no studies that have specifically looked at the effect of body weight on the efficacy of oral emergency contraception, however some analysis of studies into levonorgestrel have shown an association between pregnancy risk and body mass index.

It is not recommended that women with a high body mass index stop using emergency contraception if needed, and it is also not recommended that the dose be increased. If you have any concerns that the emergency contraceptive pill has not been effective for you, it is best to take a pregnancy test to confirm or follow up with your GP.

We also received a comment from Dr Mary Stewart, who is the Acting Medical Director at Family Planning NSW about the findings and how they relate to women in Australia.

An alternative form of emergency contraception is the copper IUD device (that also offers ongoing contraception), although Dr Stewart said getting an IUD within the five-day time frame can be difficult.

Ultimately, Dr Stewart said there hasn’t been enough research done on the correlation between weight and the efficiency of the morning-after pill to make any absolute conclusions.

“My understanding is that there is insufficient evidence about efficacy at higher BMIs for levonorgestrel EC, however in the absence of an alternative, the emergency contraceptive pill we have, which is extremely safe, is still likely to offer some benefit in preventing an unintended pregnancy and is better than nothing,” Dr Stewart said.

“Obviously there are considerations to be had about effective contraception and women should be aware of all their options,” she said.

Similarly, AMA’s OBG spokesperson Dr Gino Pecoraro says more research is needed.

“It certainly sounds like something we need to be aware of. And the big thing here is that people need to understand that it’s about emergency contraception. What we really need to make sure is that emergency contraception is something that is hardly ever needed,” Dr Pecoraro said.

“People need emergency contraception because either the condom broke, they weren’t expecting to have sex on that occasion so they weren’t prepared. Or that they didn’t take their usual method of contraception or it didn’t work for whatever reason. So if we can make that the smallest possible group that’s the first thing we can do.”

“Those so-called long acting reversing contraception are much more effective because they take away people mistakes like forgetting to take the pill,” he said.

Dr Pecoraro said anyone who is concerned by the findings should consult a health care professional.

“The most important thing is that they need to go and see their doctor,” he said.  “Because they need to have a full history… It also says in other studies that it depends where you were in the cycle. If you were around the mid cycle which is the most fertile time when ovulating, than you’re at much greater risk than someone who’s at, say, day 27.”

“Nothing takes the place of history and examination by your trained doctor.”

Editor’s note: We don’t bring this post to alarm you, just to make you aware. Just as every doctor we spoke to pointed out, a lot more research needs to be done before we draw any definite conclusions.  But in the meantime, please share this post with women who are close to you so that they can be aware too.

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