IVF - What are the chances of success?

IVF - What are the chances of success?

IVF - What are the chances of success? 

Success is dependent on a variety of different factors, and is usually determined by the number of live births rather than achieved pregnancies.


The first success, however, is pregnancy. If this is achieved, a fertility specialist is likely to then refer a woman to her gynaecologist (or obstetrician), or another pregnancy specialist for prenatal monitoring and care.

If pregnancy is not achieved, a woman will need to stop taking progesterone. Within a week, a woman will likely experience her menstrual period. It can happen that a menstrual period does not occur or a woman experiences unusual bleeding. If either of these things occur, a woman should contact her doctor for a thorough check or examination.

If a woman is keen to undergo another cycle of treatment, a fertility specialist will repeat the process once the body has settled (healed) and possibly advise options and adjustments which can be implemented to try and improve chances of pregnancy the next time around.

Pregnant woman holding little blue baby socks.

Live birth

The real success is a healthy 9-month pregnancy and birth of a baby (or babies) as a result of IVF treatment. The success rate of being able to give birth to a healthy baby depends on the following factors:

  • A woman’s age: Pregnancy is more easily achievable if a woman is younger. Once a woman reaches her 40s or older), a successful pregnancy becomes more difficult to achieve, especially if she uses her own eggs. A woman in her 40s may sometimes be advised to consider using donor eggs from a younger woman as a way to improve her chances of pregnancy through IVF methods. Age is a major factor when it comes to IVF success. A woman who is 35 years of age can have approximately 39.6% chance of success (using her own eggs). A woman who is younger has a success rate of more than 40%. Chances creep towards the 20% mark between the ages of 35 and 37, and dramatically decreases from there in the years before reaching 40. A woman over 40 has as much as 11.5% chance when using her own eggs. Women who are aged 43 and older have less than a 10% chance of success.
  • A woman’s reproductive history: Women who have experienced pregnancy or given birth before undergoing IVF treatment can sometimes have higher success rates than those who have not. Success rates for women who have undergone IVF treatment multiple times and not achieved a pregnancy, are also lower.
  • The cause of infertility: A normal egg supply (menstrual cycle) has shown to improve the chances of success using IVF methods. Certain conditions making conception difficult, such as endometriosis, fallopian tube blockages or damage, sperm problems or unexplained infertility can lower the odds of success through IVF.
  • Various lifestyle factors: Substance use (or abuse), such as that of alcohol, recreational drugs or cigarettes (smoking) can reduce a woman’s chances of being able to fall pregnant through IVF methods. Excessive caffeine intake also has an influence, as do certain medications and problems with obesity. Did you know that smoking can affect a woman’s success rate by as much as 50%?
  • Embryo transfer methods: Some embryo transfer methods have higher success rates than others for various reasons. This would have been discussed during the initial preparation stages prior to treatment being commenced. Not all embryos (whether freshly used or after being frozen and thawed) survive the dividing and developing process which needs to take place before implantation. The more developed an embryo, the higher the chances of a successful pregnancy.
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