Negative side effects of oral contraceptives

Around 100 million women around the world use oral contraceptives, better known as 'the pill'.

In the UK, 27% of women between 16 and 49 use the pill, making it the most common form of contraception. (2007). In the US, 30% of women practising contraception use the pill (2002).

The reasons for the popularity of the pill are fairly obvious; it is convenient, does not interrupt sex, and has excellent efficacy (over 99%) if taken correctly.  However, there are certain drawbacks to oral contraceptives, which, though well documented, seem to have been largely ignored or misunderstood by the general public.

Depression and mood swings

There have been some scientific studies performed which show that some women can experience depression while taking the pill.

One study (2009) showed that psychiatric disorders such as anxiety and depression are common among women who report adverse mood effects related to oral contraceptives.

A review of several studies showed that while most women don't report negative mood changes whilst on the pill, and may experience positive effects, those with a history of depression are likely to find their mood worsening.

It has also been shown that women who experience negative emotional PMT before starting to take the pill are more likely to undergo adverse mood changes if they choose a pill with a high oestrogen level, whereas women who have not previously suffered from PMT are more likely to experience adverse mood changes if they choose a pill with a high progesterone level.

One small study (2005) also suggested that the incidence of depression-like symptoms in healthy women with no history of depression are significantly higher for those taking the combined pill than non-users.

Overall, however, there has been very little scientific study which specifically focuses on the effects of the pill on mood, due to the difficult nature of such research. As a result, the effects tend to be downplayed. Health practitioners are not required to ask women about their history of depression, or explain the possible psychological side effects the pill may have. The information leaflets given out with the pill do mention that 'mild' depression is a possible side effect, but they also say that it is temporary and should disappear in a period of months. This is at odds with the overwhelming anecdotal evidence from women who say that taking oral contraceptives has severely affected their mood.

A quick search in internet forums reveals hundreds of women who complain of effects ranging from weepiness, irrational anger and unsociability to relationship breakdown and even suicidal thoughts. Many of these women have spent years dealing with their symptoms before associating them with the pill, only to find that they improved dramatically when they stopped taking it. Whilst this cannot be taken as scientific evidence, the sheer volume of these reports suggest that there may be psychological side effects of the pill that have not been sufficiently researched by the medical community.

Decreased sexual enjoyment

Another reported side effect of the pill has been a loss of interest in sex, and a decrease in sexual thoughts.

There have been a few studies in this area that suggest that certain chemicals present in oral contraceptives lower womens levels of plasma-free testosterone, which can deplete sex drive. One study (2003) showed that more women using the combined pill suffered from vaginal dryness than non users.

Recent research has suggested the possibility that the decrease in libido may continue even after the pill has been discontinued. One study showed that the levels of SHBG, a testosterone binding globulin which may limit sex drive, remained elevated for up to one year after discontinuation. The levels of SHBG among menopausal women suffering from sexual dysfunction were seven times higher for oral contraceptive users than for non users.

Again, these studies are contradicted by many others which indicate little negative effects on libido, or even positive effects, but anecdotal evidence seems to support the idea that the pill can lower libido in some women. Many have reported complete loss of interest in sexual activity, painful intercourse, and vaginal dryness, which in some cases does not improve for a long time after discontinuation.

Some studies include the suggestion that women report a loss of libido because they expect sexual appetite to increase when on the pill, and therefore are disappointed when their sex drive remains normal. The likelihood of such a claim is questionable.

Headaches, breast tenderness, pelvic pain

A study in 2000 showed that women who have a oral contraceptive regimen that includes a 'pill free' week are likely to suffer from hormone withdrawal symptoms in these 7 days, which leads to symptoms such as headaches, breast tenderness, bloating and pelvic pain. It has been suggested by researchers that the 'pill free week' types of oral contraceptives should be discontinued due to these side effects.

Though headaches can be a part of normal PMT, it has been shown that many women experience more migraines after starting to take the pill. It has also been suggested that women who suffer from migraines should not be prescribed the pill, since it can aggravate symptoms, which may not subside for up to a year after discontinuation.

Overall, though many women continue to use the pill with no adverse side effects at all, evidence does show that some women can find themselves being badly affected by it. Doctors are generally only too willing to prescribe it, on the basis that the 'minor and temporary' side effects are a price worth paying to avoid pregnancy. It may also be that the speed and convenience of prescribing the pill leads to other methods such as the coil (IUD), the diaphragm (cap) or vaginal sponges being ignored. Many women report that they have found it difficult to switch to another method of contraception because their doctor has been so enthusiastic in recommending the pill.

It is worrying that there is so much anecdotal evidence that oral contraceptives can cause severe side effects, and yet very little scientific research has been done on the subject. Most women remain so unaware of the potential problems that they can take years to associate physical and psychological problems with their contraception.

Hormonal contraceptives work by preventing the natural functioning of the reproductive system. Many women find this innately worrying, which is not surprising when you consider it in relation to other natural functions. Pills that suppress hunger, or a need to sleep, are viewed with natural suspicion and often condemned by the medical profession, so why are pills that suppress periods and the menstrual cycle so readily accepted?