Can IVF cause breast cancer? Are IVF babies abnormal? In this article we’ll teach you more about long term outcomes of IVF for mothers and babies…
IVF long term outcomes:
The first IVF birth occurred in the late 1970’s. To date, more that 5 million children have been born through IVF.
As it is a relatively new technology (in the grand scheme of things) there have been some concerns about whether IVF conceived people may suffer long term health problems. There have also been concerns as to whether women who have had IVF treatment (whether successful or not) may be at risk of long term health problems.
Happily, studies to date overwhelmingly show that our fears are largely unfounded.
Do IVF babies have more birth problems?
The answer is yes, but it’s complicated.
Most of the children born from IVF appear healthy. We have noticed a small increase in health problems, such as low birth weight, premature birth and congenital birth defects.
Some of these long-term health effects may be encoded by epigenetics.
What is meant by the term epigenetics?
Biological mechanisms that regulate genes are called “Epigenetics”. This refers to “switches” which control whether genes are turned on or turned off. Events in early development, including in embryonic development, can potentially influence health in later life. Epigenetics plays an important role in this process. IVF in theory has the potential to alter epigenetic gene expression with to date unknown consequences.
Epigenetic changes have been identified in many chronic diseases such as diabetes, cancer, and psychiatric disorders.
What are some confounding factors?
Fertility treatment is often needed in the context of women and couples having medical risk factors for disease. These include more advanced age and underlying pathologies or disease processes that result in their infertility.
What about the woman’s health after IVF?
In IVF treatment, hormonal treatments are administered that cause transient very high levels of female sex hormones (oestrogen and progesterone) in the blood.
The question has been asked whether women who have had IVF have an increased lifetime risk of cancer, especially those cancers which are known to be hormone sensitive (hormone receptor positive).
Of particular concern have been cancers of the breast and ovary, but other cancers have also been considered.
Because women having IVF are generally relatively young and healthy, cancer occurs rarely in this group. Data is generally taken from observational cohort or case-control studies.
These kinds of studies are broadly criticised as having methodology flaws and biases. Examples of problem include small sample size studying rare diseases, heterogeneous or mixed populations and treatments with a limited amount of time for later follow-up.
To confuse matters further, infertility itself is a risk factor for certain cancers including those of the breast, ovary and uterus. Having babies early in life is protective against developing these cancers.
What do we know at this point?
Reassuringly, most studies show that IVF does not increase the risks of invasive ovarian cancer, malignant melanoma or cancers of the endometrium, cervix, breast, thyroid or colon.
IVF may very modestly increase the risk of borderline ovarian cancer. This cancer is very rare (whether a woman has had IVF or not) and has a relatively favourable prognosis.