Gynaecologist, Sumayya Ebrahim, tells us about the contraception options for women with breast cancer.
More and more younger women worldwide are being diagnosed with breast cancer. What was traditionally a disease mainly affecting older women close to or beyond menopause, is now no longer so.
While chemotherapy can push a woman on the cusp of menopause, right into it and make it no longer possible for her to bear children, the situation is different in younger women. There still remains a chance that younger women could fall pregnant during the course of their diagnostic tests and the early stages of their cancer treatment. Should this occur, the repercussions are enormous: their breast cancer treatment plan may have to be altered or the pregnancy may have to be terminated. Neither options are as ideal as preventing the pregnancy in the first place.
Even in a young woman, breast cancer chemotherapy will have an affect on fertility. Usually, it makes a woman infertile during the course of the treatment and for a period thereafter. In some cases, though, fertility never returns. The bottom line is that the effect is distinctive for different women. Age seems to play a huge role: the younger a woman is at the time of chemotherapy, the higher the likelihood that fertility may return.
Which route to take?
It would make sense to choose a contraceptive option that has no impact on hormones that can cause a cancer recurrence or even interfere with ongoing treatment. As a general rule, non-hormonal contraception is recommended.
By far, the most obvious choice would be the male condom. This method has the advantage of being used only when necessary. It also protects against sexually transmitted infection. It can be 2% or 98% effective in preventing pregnancy, depending on how it is used and if there are any accidents that occur when using it.
The most commonly prescribed method is the copper intrauterine device. It is highly effective in preventing pregnancy. An added attraction is that it is completely non-hormonal. It is also, what is called, a fit-and-forget method; the user just has to endure the fitting procedure, and there is no daily commitment or pill taking. It can remain in place for between five to 10 years, depending on the device fitted.
Natural family planning methods e.g. cycle timing, cervical mucus and temperature checks, or withdrawal before ejaculation from the vagina. Today, there are many apps, such as Clue (iOS only) or Dot (iOS and Android), that can be downloaded onto your smartphone. These can track your cycles and body changes, and then alert you to when your most fertile time of the month occurs. The more regular your cycle is, the more accurate the app is. Irregular or missed periods make them less reliable. They are also reliant on your ability to read the physical changes that occur in your body.
How does the copper intrauterine device work?
The copper in the device kills the sperm as they get into the uterus, and it also causes an inflammatory reaction in the lining of the uterus that prevents implantation of a fertilised egg. For this reason, it can be regarded as a method that induces early abortion and some people may have a life-choice objection to this method.
It does make the period heavier and more painful, however, women on chemotherapy are very likely to stop menstruating. In some women it can trigger repeated bladder or pelvic infections. It also offers no protection against sexually transmitted diseases or HIV infection.
This latex device needs to be fitted by a medical doctor or family planning nurse. It has to be inserted into the vagina just before intercourse and left in for a period of eight hours thereafter. The efficacy is enhanced by the simultaneous use of a spermicide. This device works by covering the cervix and so preventing sperm from travelling up into the uterus. The spermicide will, in addition, kill the sperm. It is not a very popular and not a commonly used contraceptive in South Africa, and is often difficult to find.
Vasectomy (male sterilisation)
Some couples will choose this method in order to avoid further interventions in a woman already undergoing treatment for breast cancer. It is usually a quick procedure that can be done, under local or general anaesthesia.
In this procedure, the tubes that carry sperm from the testes to the penis is cut. This method is only fully effective once a semen test, done afterwards, confirms no detectable motile sperm. It may take a few months for this to happen.
Once the vasectomy is performed, it is regarded as a permanent form of contraception and can be reversed only under special circumstances. It is usually only recommended for couples who have completed their families.
Tubal ligation (female sterilisation)
There are many surgical techniques to achieve a final result of blocking the fallopian tubes or cutting them. By doing this, sperm will no longer be able to reach the eggs to fertilise them. Again, this is generally regarded as a permanent form of contraception. Reversal can be done, but may involve various surgical procedures with no guarantee of success. It is generally a good method for women who have the fortitude to undergo another surgery, in addition to their cancer treatments.
There is no clear evidence that it is safe to use any form of hormonal contraception in breast cancer survivors. The following contraceptives would be considered hormonal methods:
• Combined oral contraceptive pills (COCP) e.g. Femodene, Yaz and Mercilon.
• Contraceptive patch e.g. Evra.
• Contraceptive vaginal ring e.g. NuvaRing.
• Progesterone-only pill e.g. Microval.
• Progesterone implant e.g. Implanon.
• Progesterone injections e.g. Depo-Provera and Nur-Isterate.
NB – a special point to consider
Failure rates for all methods of contraception decrease as fertility naturally drops with advancing age. This makes methods that have an unacceptable failure rate for a younger woman, appropriate for a woman in her 40s.
Since fertility will be further decreased following chemotherapy, a contraceptive method with a higher failure rate may be acceptable in a small population of women, who are still menstruating after breast cancer treatment. For example, while condoms and natural family planning methods may not be effective in a 35-year-old, they may be perfectly adequate for a 45-year-old on chemotherapy.
What about the Mirena?
The Mirena is an intrauterine device that releases a low sustained dose of a progestin (levonorgestrel) on a daily basis over a five-year period. The dose is meant to be so low that the progestin does not enter the bloodstream and so not exert any effect on the breast. Basic scientific data, however, suggests that progestins can have an effect on breast tissue – it encourages growth as well as cell division. This depends on the timing, type and amount of progestin used.
Now, not only will women who have recently had Mirenas inserted tell you, but studies have also shown that one of the initial nuisance side effects of the Mirena is breast tenderness. Therefore, it would seem that there is some hormonal effect on the breast, at least in the first few months after insertion, when levonorgestrel levels are highest. Thus an effect on breast cancer risk cannot be dismissed at this time. More data on safety is needed, before this device can be recommended as a first-line contraceptive for breast cancer survivors.
Some studies indicate, and researchers have recommended that the Mirena device can be used safely in some patients on tamoxifen treatment, where there may be concerns about developing an endometrial cancer of the uterus.
The progestin in the Mirena can exert a protective effect on the endometrium and thus act to prevent a tamoxifen-induced uterine cancer. Of course, this benefit has to be balanced by the potential simultaneous risk of inducing a breast cancer recurrence. This decision needs careful consideration by the entire treatment team.