07 May Epigenetics: can IVF affect your baby’s genes?
Epigenetics is a branch of science that’s increasingly relevant to pregnancies. And IVF pregnancies – especially using donor eggs or donor sperm. Why? Because epigenetics looks at the way lifestyle factors might affect your baby’s genes. If you have a donor-egg child, it could mean she takes after you, after all.
Epigenetics is new, and very complex. Basically, everyone has a unique set of genes, set out in a particular sequence. Epigenetics looks at the millions of markers dotted around those genes. Think of them as genetic traffic lights.
The gene sequence can’t be changed. But these markers could alter the way the genes are ‘expressed’. What inherited genes end up doing, or not doing, could be based on lifestyle factors. Think of a music album. You can’t alter the music. But you can change the volume and the tracks you choose to play.
So what role does epigenetics play in IVF treatment? Patients using donor eggs think their babies won’t take after them. But that’s not quite true if you believe in epigenetics. Your uterine environment, stress levels, diet and behaviour may influence the way your baby’s genes are expressed. This offers, in mots cases, comfort to donor-egg patients. There may be more of you in your child than you think.
A study of maternal diet and baby genes found that a mother’s diet at the time of conception may alter gene expression. The DNA of the babies conceived in the rainy season was expressed differently to those conceived in the dry season – when maternal diet wasn’t that great. The study concluded that a healthy diet is important when you’re trying for a baby.
Epigenetics is linked to events, not just lifestyle. In 1944, the Nazis stopped food getting into parts of the Netherlands. Thousands died of malnutrition. The babies that survived were, unsurprisingly, underweight. But so were a number of babies born, years later, to those children. Their genes had been damaged. The DNA sequence was the same, but the expression of those genes had been passed down. Something influenced the marker that turned on the gene, or genes, linked to weight.
Does IVF itself expose the fetus to epigenetic dangers? A small Danish study suggested that babies born via assisted reproduction (i.e. IVF) had a slightly higher chance of getting childhood cancer. One possible reason was that epigenetic changes might occur in the IVF process. Manipulation of the embryos and IVF medication may be the reason. But the risk is minimal.
A more recent study, in 2019, found epigenetic differences between IVF babies and non-IVF babies. But those differences vanished in later life, and didn’t impact on their health. Another 2019 study into fertility treatment and epigenetics did see a small genetic health risk to IVF babies. Very small.
Epigenetics is very new. It’s too early to claim lifestyle and environmental factors before and during pregnancy (whether via natural conception or IVF) affect the baby’s genes in a significant way. Or that personality traits of the birth mother might impact on the genes of her donor-egg child.
But there’s clearer evidence that a healthy lifestyle before and during pregnancy makes your baby epigenetically better off. If epigenetics is about parental health, it’s a wake-up call to the benefits of looking after yourself.