Skip to main content

Contraception Success Rates

The success of your contraception is impacted by much more than ‘success rates’, important though these are. Provided you’re selecting from a range of effective methods the following also need to be considered for you to choose the most effective method, or combination of methods, to suit your needs.


  • Informed Choice: Become your own contraception expert
  • Understanding methods of contraception and what they offer
    • Barrier Methods
    • Spermicides
    • Intrauterine Devices (IUDs)
    • Sterilisation: biochemical
    • Sterilisation: surgical
    • Natural methods
      • Fertility awareness
      • The Mucus Method
      • The Temperature Method
      • The Sympto–thermal Method
      • Natural Fertility Management
      • Mixing and matching methods
  • Understanding success rates and making them work for you
  • Success rates for chemical and surgical methods of contraception
  • Success rates for barrier methods of contraception 
  • Success rates for Natural Fertility Management, fertility awareness methods and withdrawal

Informed Choice: Become your own contraception expert

Given that for most of your fertile life it’s likely you’re not wanting to make babies when you make love, it’s well worth taking the time to fully explore your contraceptive options. This will contribute to the quality of your sexual experience and your relationship as well as the effectiveness of the method you choose. This is as true for men as it is for women, and potentially for many more years of men’s lives than of women’s.

It’s very likely that in the course of your fertile life different methods of contraception will be appropriate for you at different times.  When considering these you’ll need to think about their effect on your health, how they work, their usefulness in different situations as well as their quoted success rates. If you have purchased The Complete Guide to Optimum Conception you will find more about how to choose a contraception method during your preconception preparation in Module 5.

In the heat of sexual activity you may not be so focused on precautions, nor is this the best time for clear thinking but, like a birth plan, a carefully thought through contraception plan means the clear thinking has already taken place, so you are free to enjoy the moment.

Health professionals and family planning policy makers are focused on preventing unplanned pregnancy. Their concerns generally don’t consider an individual woman’s capacity to know her own body and make choices accordingly. Therefore, approaches that promote gaining that knowledge tend to be given less value by those involved in delivering public contraceptive services.

Are you managing your reproductive health care with informed consent?

As with all health care, informed consent is central to the provision of contraception and it’s crucial for you to have clear information about all available contraception methods in order to manage this important area of your life successfully.

Five ways to inform yourself:

  • Learn as much as you can about your body as a woman. See The Natural Fertility Management Contraception Kit or The Complete Guide to Optimum Conception.
  • Assume that your body’s natural rhythms and processes are there for a reason.
  • Research all health care alternatives and remember that ads, and top internet sites, are placed there by those who have the money to do so. This doesn’t mean they necessarily have the best information.
  • Pay attention to how you feel and follow your instincts.
  • And consult knowledgeable, health conscious women about how they manage their reproductive health. [i]

Health care professionals generally understand informed consent to mean that there has been a discussion about the nature of the drug or procedure, reasonable alternatives have been considered and the risks, benefits, and uncertainties are all understood. You can then decide to accept or reject the drugs or procedures with full awareness of consequences either way. Anything short of this, to your satisfaction, is not informed consent.

Understanding methods of contraception and what they offer

 Methods of contraception typically work by ‘contraception’, ‘abortion’ or ‘sterilisation’; on their own, or in combination.

‘Contraception’ refers to those methods that prevent viable ovum and sperm from meeting in the fallopian tube and resulting in a conception.

‘Sterilisation’ refers to those methods that supress or eliminate the natural reproductive processes, or pathways, within our bodies. Surgical sterilisation is designed to be permanent and chemical sterilisation is designed to be temporary.

‘Abortion’ refers to those methods that prevent a fertilised ovum from continuing to develop naturally, or implant in the uterine lining, causing it to die, its cells to break down and pass unnoticed with a woman’s next period.

Be aware that some methods labeled as ‘contraception’ may actually be working as abortion or sterilisation.

Barrier Methods

Barrier methods physically prevent sperm from reaching an egg, or ovum. These include condoms, diaphragms, the cervical cap and female condoms. These are generally made of rubber, although plastic versions are widely available now for those who are allergic to rubber or just prefer plastic.

The beauty of barrier methods is that you use them when you need them, and are free of them when you don’t. Condoms are, of course, de rigeur for preventing sexually transmitted infections (STIs) when you (or your partner) are sexually involved with other, potentially infected, partners. If you aren’t sure of your partner’s history or infection status, then use a condom. Male and female condoms both prevent STIs.

An experienced health provider will generally fit you for a diaphragm or cervical cap which can then be purchased from a pharmacy. Some diaphragm brands are now available online with instructions for checking fit and correct position. You can also find more about this in Natural Fertility or The Natural Fertility Management Contraception Kit.

Female condoms are a form of condom that fits inside the vagina and over the labia minora, and collects sperm and prevents infection with STDs.  An inner and outer ring keeps it in place. These may be preferable in some relationships. 

Barrier methods are a contraceptive method.


Spermicides contain chemicals – manufactured or naturally occurring – which kill or disable sperm, preventing them from swimming up into the uterus and fallopian tubes to fertilise an egg. Commercial spermicides come in many different forms –foam, jelly and suppositories and can be purchased from pharmacies. No prescription is necessary for spermicides.

Some commercial spermicides cause irritation for some users, and more natural, low-allergenic brands are available – check online.

Spermicides are commonly used in conjunction with barrier methods to increase the effectiveness of each. Some brands of condom come already impregnated with spermicides.

Spermicides are a contraceptive method.

Intrauterine Devices (IUDs)

Inserting one thing or another into the uterus as a way to prevent pregnancy has been used for millenia.  Current IUDs are either inert (ie they work by irritation) or they may release copper or synthetic hormones into your uterus. The copper releasing IUD is known as Cu-IUD and the levonorgestrel (a synthetic progesterone) releasing IUD is known as LNG–IUD or IUS (intra-uterine system).

All types of IUD work contraceptively, in part, by their effect on the endometrium (uterine lining) and the uterine and tubal fluid, as the body reacts to the presence of the irritating foreign body (the IUD). The copper IUDs increase the foreign body reaction which leads to a range of biochemical changes in the endometrium, affecting enzyme systems and hormone receptors.  Copper ions from the Cu–IUDs are toxic to sperm and zygotes (fertilised ova). IUDs containing levonorgestrel also add the effects of synthetic progesterone (progestin), similar to the progestin only, or mini, Pill.

IUDs require a well trained doctor to ensure correct positioning, and timing relative to the menstrual cycle, for insertion of the device, in order to avoid the dangers of perforating the uterus. About 5 – 20% of inert or copper IUD users have the device removed because of bleeding and pain within the first twelve months. Of the remainder, about half report annoying bleeding.[ii]

IUDs are a contraceptive and abortive method.

Sterilisation: chemical

There are fundamentally two types of Pill available: the most commonly used is the combined oral contraceptive Pill (COC), which contains synthetic oestrogen and progestin and may be mono or multi phasic – with variable quantities of hormone, creating two or three phases during the cycle.

The COC works by

  • inhibiting ovarian activity (sterilisation)
  • altering the uterine lining to prevent implantation (abortion)
  • making the mucus in the cervix hostile to sperm (contraception).

There are also progestin-only pills (POPs). Often called the Mini-Pill, these Pills have no oestrogen, so may not inhibit ovulation, but generally work by altering the uterine lining and cervical mucus as with the COCs.

Other modes of delivery of synthetic hormones:

  • Depo-Provera, Implants, LNG-IUDs, IUSs – use progestin like the POPs
  • patches and vaginal rings release synthetic oestrogen as well as progestin, like the COCs.

For more information about the Pill and other hormonal contraception and their impacts see
The Pill: are you sure it’s for you?


Many women only realise the effect the Pill has had on them when they come off it. They often report a much greater feeling of wellbeing, both physical and psychological, as well as see improvements in specific conditions.       Francesca Naish

For more about the effects of hormonal contraception on your fertility and health see The Natural Fertility Management Contraception Kit or, if you plan to conceive soon, The Complete Guide to Optimum Conception.

Sterilisation: surgical

Many couples who have completed their families opt for surgical sterilisation, either male or female. However, even with these procedures there is still a slight risk of pregnancy as tubes sometimes grow back together or the waiting period after vascectomy is not well understood.

Female sterilisation, or tubal ligation, involves blocking or cutting the fallopian tubes, thus preventing the ovum and sperm from meeting. These proceedures require surgery and a skilled specialist to perform it. Once performed, female sterilisation is permanent.  If a later pregnancy is desired a woman would need in-vitro fertilisation (IVF) techniques for a chance to conceive a baby.

Male sterilisation, or vasectomy, involves cutting or blocking both vas deferens (sperm ducts) to prevent sperm formed in the testes entering the ejaculate. While vascectomy is somewhat more reversible than tubal ligation it nonetheless requires highly skilled micro-surgery to reconnect the vas deferens if a later child is desired. Even then the chances of a pregnancy diminish about 10% for each year from the vascectomy.[iii]

While male sterilisation, or vascectomy, is less invasive than female sterilisation, or tubal ligation, both are surgical and carry the usual risks of surgical procedures and depend on the skill of the surgeon.

As with all other methods side-effects of sterilisation need to be carefully researched and considered. Vascectomy, for instance, has been associated with an increased risk of cardiovascular disease, thyroid and joint disorders, cancer of the prostate, testicles and lung, diabetes and dementia. And, with tubal ligation, risks include heavier periods, premature menopause and depression, as well as damage to nearby organs.

Sterilisation methods induce infertility – either mechanically or chemically. In the case of surgery this is mostly permanent. In the case of chemical or hormonal methods this is not generally permanent.

Natural methods

Natural methods of contraception refer to those that are device and chemical free, and rely on an understanding of the processes and changing physical signs of fertility, in order to avoid any unplanned meeting of ovum and sperm.

Some of these are amongst the oldest continually used methods of contraception, and, being free and not dependant on medical consultation, can easily be used anywhere, anytime. That said, these days, technology can assist with the learning or practicing of some of these methods, for example the use of thermometers, microscopes, ovulation testers and apps. However these are optional, except where the temperature method is used on its own.

Fertility awareness is a generic term that describes a life skill a woman can gain by becoming intimately familiar with her unique cycle of ovulation and menstruation. In this way the natural methods of fertility awareness can become the basis on which a couple may then choose the best method of contraception to use when the woman is fertile, be it barrier, barrier with spermicide, alternative sexual practices or abstinence.

The ingredients for successful natural contraception are a healthy curiosity about, and friendliness toward, your own body, knowledge of how your body works, and a clear month-by-month contraceptive intention. Not essential, but ideal, is cooperation between partners.

The great secret of these methods is that, once learnt, they become more or less automatic and there is very little ‘to do’. You may revisit the learning process from time to time, at a time of change, like after giving birth, or after a period of celibacy, but otherwise the understanding you gain becomes something you just intuitively know about yourself.

Many women who have learned the Natural Fertility Management methods have expressed that the real value in learning these methods has been the deep awareness of themselves and their cyclical life. The usefulness of this for contraception becomes a handy by-product.

Discovering things about my body and how it works has been great. For my husband and I it has given us the freedom without all the negative side-effects. Adrienne

It’s great to be working with, and nurturing, my femininity and fertility instead of controlling it at all costs – to treat fertility as a life-giving process and not some form of chronic or fatal disease.  Chang

I wish I’d known all this stuff when I was 16! I’m sure I wouldn’t have given so much of my power and self-esteem away.   Lily

It’s been 12 months now since I began charting my cycle, and it’s been a real voyage of discovery about myself. A very strange, but exhilarating, experience, those first few months were: unlocking a secret code that I’d carried inside of me for about 20 years. My cycle turned out to be such a regular, striaghtforward one that I was amazed that it hadn’t always been obvious to me. But no, I’d been completely in the dark. Finding out where my ovulation regularly fell in my cycle explained such a lot about how I felt – my highs and lows and madnesses – and when. I couldn’t believe that – couldn’t understand why – my cycle had been a mystery to me for so long.   Mariana

Fertility Awareness Methods

Fertility awareness methods include all those that teach women to read their body symptoms; to know when they are fertile and when they are not.

The Mucus Method

A woman can learn to read the cervical mucus changes so she can accurately predict when her mid-cycle ovulation will occur, plan a safe lead-up to this time, and know when her egg is no longer viable afterwards. For many women, once they learn to ‘read’ their mucus it seems very clear and obvious to them.

The Temperature Method

The Temperature Method relies on the fact that a woman’s temperature is higher in the second half of her cycle, after ovulation, due to raised progesterone levels. A woman using this method will take her temperature at about the same time each day – upon waking is standard – and watch for a clear and sustained rise in temperature. Used alone this method is most useful in predicting when ovulation is over and the egg is not viable.

The Sympto-thermal Method

The Sympto-thermal Method incorporates both the mucus and temperature methods, as well as charting other body symptoms that fluctuate with the cycle, like texture and position of the cervix. This collection of methods offers more clarification and confirmation of fertile and infertile times, and more flexibility if there are any health issues, like a fever or vaginal infection, which may distort one or other of the symptoms.

Natural Fertility Management

Natural Fertility Management is a unique combination of methods pioneered by Francesca Naish in the mid-1970s, in which the fertility awareness methods of mucus, temperature and other signs of fertility were combined with research on spontaneous ovulation. The result is a method that offers comprehensive understanding of our fertile and infertile times and, if practiced as taught, a very high success rate.

Natural Fertility Management includes teaching on when and how to use other methods of contraception at fertile times, ensuring seamless use of these for fertility management.

Natural methods effectiveness rates

Research on natural methods has found a clear difference between effectiveness rates when these methods are well taught and when they are not. A vague guess at a ‘safe time’ is obviously going to be a lot less effective than a clear understanding of your body signals. Once learnt, you have this knowledge and method for the rest of your fertile life and, apart from having an effective and safe contraception method, the awareness of your body and cycles can greatly enhance your self-awareness and sexual confidence.

I love the heightened awareness of my body and its cycles and the sense of self-respect and empowerment this brings. Vivienne

My partner thought it was a great idea and had absolutely no resistance to using these methods – it seemed very common sense to him and has probably given him more of an understanding of my fertility as well. Fertility awareness has also helped me to have a more complete sense of who I am as a woman and a deep appreciation of my fertility, which is very empowering.  Janette

I wish I had known what I know now about my cycles when I was an adolescent and could have enjoyed the process of my cycles as I have done for the last ten years. It is very empowering to have this knowledge and be able to use it in such an important area of a woman’s life. Tran

Natural fertility is great for your sex life and sex drive! Rheannan

The rewards of using this method have extended well beyond feeling confident about contraception. It has opened up a whole new understanding of my body, and has given me great peace of mind.  Bettina

I have been using fertility awareness for over a year now very successfully, and I may add, with much pleasure. I have learnt to understand and enjoy all aspects of my cycle. I feel more in touch with my body, more confident and empowered around my sexuality and fertility as I know exactly when I can conceive and when I can’t. Aditi

Mixing and matching methods

Effectiveness rates of various contraceptive methods are enhanced when used in combination. Classically, barrier methods are frequently combined with spermicides. Barrier methods and spermicides are often used by couples practicing natural methods – during the woman’s fertile time. By combining natural and barrier methods user fatigue can be avoided, which can sometimes compromise the effectiveness rates for those using barrier methods all the time.

The Natural Fertility Management Contraception Kit provides a thorough and precise way to learn these methods.


Understanding success rates and making them work for you

The three most important things to remember about contraception, any contraception, are that:

  1. no method of contraception is 100% effective, and this includes the Pill, implants, injections and sterilisation
  2. more important for effectiveness than the various averaged statistics of theoretical or perfect success rates, is carefully choosing a method, or methods, that best suit you, your relationship, your lifestyle, your health goals and your stage of life
  3. for maximum effectiveness of your chosen method, take the time to learn how to use it correctly on all occasions. Appropriate combinations of methods, i.e. barrier with spermicides will further enhance effectiveness.

It’s usually understood that the contraceptive methods that offer the ‘highest’ success rates are:

  • surgical sterilisation, which necessitates you being at a stage in your life where you are reasonably certain that you don’t want any more children, as well as careful consideration of side-effects and contra-indications, and
  • synthetic hormonal methods that don’t rely on daily remembrance, like an injection, an implant or an LNG-IUD.

While these do offer high success rates they also have high drop-out rates, with 30% of women who receive implants having them removed within the first year and similarly 5-20% of IUD users, as mentioned. Direct injection of hormones, such as Depo-Provera, can’t be removed, so a woman who chooses this method and finds it doesn’t suit her unfortunately just has to wait out the effects.

A recent study in the journal Human Reproduction found that a surprisingly large proportion of women become pregnant while using birth control, either through utilising it incorrectly or by using methods inappropriate for their lifestyles.[iv] Dr Martyn Walling, from the UK, has found that one third of women who go on the Pill will stop within a year because of side-effects. On the other hand, women who use fertility awareness methods are most likely to still be using the method in five years time.

Clearly, if a woman has mixed feelings about her contraception then she is less likely to use it well, lowering the effectiveness rate.

While statisticians necessarily look at the tens, hundreds or thousands of women in a study, you can find your own health / relationship / contraception balance, and discover what will work best for you. Your carefully chosen method used well over time will give you the best chance at success.

Success rates for chemical and surgical methods of contraception

The tables below draws on the success rates published by Family Planning Victoria, the National Health Service (UK) and Planned Parenthood (US). Where known, the lower rate is the user rate, the higher the theoretical rate.



Success Rate %

The Pill  (combined and mini)


Morning After Pill


Copper IUD


Hormonal-releasing IUD


Implants (eg Implanon)


Injections (eg Depo-Provera)


Vaginal ring  (eg Nuva-ring)


Skin Patch (eg Ortho Evra)


Tubal ligation & vasectomy


Success rates for barrier methods of contraception


Success Rate %



Female condoms


Condom plus spermicide


Diaphragm/cap plus spermicide


Spermicide alone


Success rates for Natural Fertility Management, fertility awareness methods and withdrawal

To assess the statistical effectiveness of Natural Fertility Management we consider the rates of each of the methods to achieve our theoretical success rate


Theoretical success rate %

User success rate %

Sympto-thermal Method*



Mucus Method



Temperature Method**






*User success rates for fertility awareness methods can vary significantly due to the difference between women and couples who are well taught and consistently practice the methods (high knowledge and motivation), and those less well taught and more approximate in their use (less knowledge and lower motivation).
**Temperature method used on its own implies abstinence in pre-ovulatory phase.
 Both mucus and sympto-thermal methods have been found to have success rates as high as 99.8 per cent in groups that are well-taught and well-motivated.
Natural Fertility Management is a sympto-thermal method, and The Natural Fertility Management Contraception Kit provides a thorough and precise way to learn these methods, including auto-hypnosis support for motivation.

[i]G. Matus, ‘Are you managing your reproductive health care with informed consent?’, Femme Fatal, <> Winter 2006. Re published by Jane Bennett and Alexandra Pope in their book The Pill: are you sure it’s for you?,with permission.
[ii]J. Guillebaud, Contraception Your Questions Answered, Churchill Livingstone, Edinburgh, UK, 2004
[iii]R. Butt, ‘Men clamour to try out silicone alternative to vasectomy’,,,1891798,00  10thOctober 2006
[iv]A. Hobson and R Grumman,  ‘Contraception secrets your doctor hasn’t told you’, Cosmopolitan, December 2003