What influences your chance of IVF success?

In vitro fertilisation (IVF) is a technique used to help a woman become pregnant, by which an egg and sperm are joined together outside the body in a laboratory (‘in vitro’, which is Latin for ‘within the glass’).

The first baby conceived by this method was born in 1978, paving the way for a new era in how babies could be conceived and thus helping to address a range of fertility issues. Since then, the methods and technology used in IVF treatment have significantly improved, success rates have risen, and millions of babies have now been born worldwide using IVF.

IVF may be suitable if you would like to conceive but you or your partner have fertility problems, or perhaps because you want to avoid passing on inherited genetic disorders to your children. Whatever the reason, opting for IVF is a big decision so it is important to understand the factors that may influence the outcome of the procedure.

The likelihood of you having a baby via IVF can be affected by a number of factors – some that you cannot change, such as your age or particular types of fertility problem, and some that are modifiable. Modifiable factors can be medical or lifestyle related. Here, we will explore some of the most important factors that could affect your chances of conceiving with IVF.

Age

Age is well recognised to be one of the most influential factors in predicting IVF success. This is because as a woman ages, both the quantity and quality of her eggs declines.IVF technology in the setting of low numbers of eggs and/or poor-quality eggs is much less successful.2

If you receive donor eggs from a younger woman, you can expect to have nearly the same chance of success as women of the age of your donor. This is because younger eggs tend to be of better quality.2

Chromosomal abnormalities (problems with the DNA-containing structures in cells) are one of the major factors contributing to IVF failure and are the reason behind most miscarriages. These abnormalities increase as we age, and at a faster rate in women – by your mid-40s, as many as 75% of the chromosomes in your eggs are likely to have abnormalities.1

Our recommendation is to start IVF sooner rather than later (there is no lower age limit for IVF treatment). Everyone’s body is unique so a comprehensive medical assessment can give a better indication of your chances of conceiving with IVF than your age alone. IVF has been used successfully to help women at all stages of their reproductive life, but it is important to understand that each case is different.

Previous pregnancy or miscarriage

If you’ve previously been pregnant, the likelihood of you having a baby during your IVF treatment may be increased – IVF is recognised as being more effective in women who have previously been pregnant and/or had a live birth.On the other hand, if you have had a miscarriage, your chances of success with IVF may be reduced. If you have experienced recurrent miscarriages (three or more pregnancy losses), you might have a particular fertility issue where IVF may not help.

We can help you narrow down the probable causes of pregnancy loss and provide recommendations on the most appropriate course of action.

Type of fertility problem

IVF can be a good option for couples having trouble conceiving as a result of certain fertility problems, such as low numbers of sperm, issues with ovulation, endometriosis or blockages of the fallopian tubes. However, IVF does not work well for everyone.

Some fertility problems respond less well to IVF, including:

  • Poor ovarian response: Sometimes the ovaries do not respond well to fertility medications and therefore can’t produce the multiple eggs that make IVF more effective. This can occur if your ovarian reserve (number of eggs in your ovaries) is low or if they are not responding to the IVF treatment. If this is the case, IVF with your own eggs may not be the best option and you may wish to opt for donor eggs.
  • Duration of infertility: Statistically, couples that have been infertile for longer are less likely to have a baby with IVF.If you and/or your partner have had problems with fertility for several years, a health assessment will be necessary to determine whether IVF is suitable for you.
  • Dual infertility: If both you and your partner have fertility problems, the chance of success with IVF may be lower. Male infertility can be challenging to address with IVF, because sperm of impaired quality do not fertilise eggs at the same rates as normal sperm. Careful testing of both partners can give a better idea of whether IVF is the right option for you.
  • Fibroid tumours: Benign fibroid tumours (tissues that grow in and around the wall of the uterus, or womb) are very common, and usually don’t interfere with becoming pregnant. Sometimes, however, they can make it difficult for the embryo to implant and grow properly. These cases can usually be surgically corrected, allowing pregnancy to occur.
  • Uterine abnormalities: Congenital uterine anomalies (i.e. problems with the uterus that develop before you are born) can reduce the chance of a successful pregnancy. Outcomes vary from woman to woman, depending on the type of abnormality, so it is important to have a full health assessment to determine the specific abnormality.

Each case is different, so it is important that you undergo an in-depth consultation and careful testing in order to understand whether IVF is the right option for you.

Lifestyle factors

Lifestyle factors such as nutrition, smoking, and alcohol consumption can affect you and/or your partner’s fertility. Even though many factors influencing IVF success are out of your control, you may be able to improve your chances by understanding and addressing the following factors.

Obesity and nutrition

Being overweight or obese can have an impact on your fertility. Obesity (BMI 30 to 35) has been linked to miscarriage following IVF, and is also associated with reduced pregnancy rates in women and lower sperm quality in men.It is thought that an increase in leptin (the hormone secreted by fat tissue) can affect menstruation, in turn leading to worse IVF outcomes.

The ‘Mediterranean diet’, which consists of a high intake of vegetables, legumes and vegetable oils, and a low intake of fast food, has been linked to a higher pregnancy rate and may potentially improve the chances of pregnancy after IVF.This could be due to the presence of linoleic acid in vegetable oils, which may be beneficial for the implantation of the fertilised embryo.

Smoking and alcohol

You and/or your partner should quit smoking if you’re considering IVF. Smoking can cause damage to the sperm’s DNA and can affect the reserve of eggs and their ability to become fertilised.Smokers often require twice as many IVF cycles to conceive than non-smokers.You can also be affected by second-hand smoke – fertility is reduced in women exposed to cigarette smoke from their partners smoking at home.9

Drinking alcohol can also reduce your chances of IVF success, as it affects pregnancy and miscarriage rates. Just one can of beer per day before week 1 of the sperm or egg collection has been linked to reduced IVF success.10 Drinking alcohol when you’re trying to conceive – whether through IVF or not – is not recommended. This is because alcohol can cross the placenta and affect the development of your baby, potentially leading to problems such as fetal alcohol syndrome, stillbirth or physical disabilities.

During an IVF cycle, you should focus on eating healthy, balanced meals. Maintaining a healthy weight is extremely important, and your BMI range should ideally be between 19 and 30 before attempting IVF.Consider reducing your alcohol intake, and if you or your partner smoke, quitting is the best option.

Deciding whether IVF is right for you

When considering your fertility, there is no one-size-fits-all approach. As with all aspects of fertility care, the best decision for you is the one that is personalised to your individual situation.

For more information about IVF, please visit this page. And if you would like to discuss your options with one of our fertility specialists, please call Newlife IVF on (03) 8080 8933 or book online via our appointments page.

References
  1. van Loendersloot LL et al. Hum Reprod 2010;16:577–589.
  2. Sabatini L et al. Reprod Biomed 2008;17:10–19.
  3. Nelson SM, Lawlor DA. PLoS med 2011;8:e1000386.
  4. Roberts S et al. Health Technol Assess 2010;14:1–237.
  5. Fedorcsak P et al. Acta Obstet Gynecol Scand 2000;79:43–48.
  6. Vujkovic M et al. Fertil Steril 2010;94(6):2096–2101.
  7. Frins S et al. Reprod Biol and Endocrinol 2015;13:134.
  8. Younglai EV et al. Arch Environ Contam Toxicol 2002;43:121–126.
  9. Zenzes M et al. Mol Hum Reprod 1998;4:159–165.
  10. Klonoff-Cohen H et al. Fertil Steril 2003;79:330–339.