Why does premenstrual syndrome occur? Despite extensive research the answer remains uncertain. Symptoms only occur between puberty and the menopause, and they disappear during pregnancy, so the link with monthly ovarian and hormonal activity is obvious.
It would therefore seem logical to expect that any contraceptive method that stops the monthly cycle and ovulation should lead to an improvement in symptoms and be an ideal choice for PMS sufferers. Unfortunately that is not always the case. Contraception for the woman with premenstrual syndrome is often a bit of a ‘hit and miss’ affair. GPs are uncertain as to the best method to prescribe. Sufferers will often work their way through all the contraceptive methods and eventually settle for the ‘least worst’ option.
Combined contraceptive pill
The combined contraceptive pill which contains two hormones – oestrogen and progestogen – is usually taken for twenty-one consecutive days followed by seven pill-free days during which a withdrawal bleed or ‘period’ occurs. The exact role and effect of combined hormonal contraception in the treatment of PMS is subject to continuing study and research.
Many women find this a very easy method: as well as providing excellent contraception it has the added advantage that periods are lighter and less painful.
Symptoms may reappear in the pill-free week so if this happens it is quite safe and acceptable to take the pill continuously, thus keeping hormone levels constant rather than having monthly variations. Break-through bleeding may occur initially when starting taking the pill ‘back to back’ in this way. If this lasts for more than three or four days it is best to take a break from the pill for four days and then restart taking the pill (contraceptive efficacy will not be affected). This continuous pill-taking can only be used when the monophasic pill is prescribed, which contains the same dose throughout the packet. Pills that have varying doses (biphasic or triphasic), or those that have seven ‘dummy’ or placebo pills, should not be taken in this way.
Whilst many women’s PMS symptoms improve whilst taking the contraceptive pill, a significant number of women find their symptoms appear to get worse and may even last throughout the month. This is thought to be due to the effects of the progestogen content rather than the oestrogen. As combined pills contain different types of progestogen it is well worth trying a pill with a different progestogen (e.g. drospirenone) to see if there is any improvement in symptoms. Any change of pill should be tried for a minimum of three months before any conclusion can be reached about the benefits or otherwise. Chopping and changing pills too quickly and too frequently makes it difficult to evaluate the benefits and side effects.
There are now two new combined contraceptive pills that do not contain the synthetic oestrogen (ethinyl oestradiol) but an oestrogen that is identical to natural human oestrogen. We need more research as to whether these pills would be more beneficial to the PMS sufferer than the standard pills but they may well be worth trying.
Contraceptive ring and the contraceptive patch
The contraceptive ring and the contraceptive patch both contain the two hormones, oestrogen and progestogen, and like the combined pill may be of benefit to some women. Again, they should be tried for a minimum of three months.
Progestogen only pill or mini pill
The progestogen only pill or mini pill can also stop women ovulating.
Though some GPs consider it useful in treating PMS, most studies
have detected no benefit and some women even find their PMS symptoms worsening.
Injection of depot progestogen and the contraceptive implant
The three monthly injection of depot progestogen and the contraceptive implant contain only progestogen (no oestrogen). Some women find these two methods helpful but they are not usually recommended for PMS sufferers as the progestogen component can cause worsening of their PMS symptoms.
Progestogen releasing intrauterine system (Mirena) or coil.
The other method of hormonal contraception is the progestogen releasing intrauterine system (Mirena) or coil.
This option worth can be particularly useful for women who suffer from heavy and painful periods but does not usually help PMS. It reduces blood loss significantly and also suppresses ovulation in about 20% of cases. The Mirena lasts for five years and users should expect unpredictable light bleeding or spotting in the first few months while it is settling down. Having a Mirena fitted means the progestogen is where it is needed (i.e. the lining of the womb) and is not circulating around the whole body as with the progestogen only pill, injection or implant. However, even these low systemic levels can occasionally produce adverse PMS symptoms in those who are progestogen-intolerant.
The intrauterine device (IUD) or coil will not have any effect on PMS symptoms. It can make periods heavier, longer lasting and more painful so is perhaps not an ideal method for women who are already feeling pretty low at this time of the month.
Barrier methods
Barrier methods (condoms and the diaphragm or cap) usually will not have any impact on PMS symptoms. These are not as effective as hormonal methods but they have the added advantage of protection from sexually transmitted infections.
Female sterilization
Some women mistakenly think that female sterilization will solve their premenstrual symptoms but this is not the case. They can’t become pregnant but an egg will still be released monthly from the ovaries and so they will still experience the same hormonal mood swings as before the procedure.
Emergency contraception or the ‘morning after pill’
Use of emergency contraception or the ‘morning after pill’ should have no effect on premenstrual symptoms.