In Ireland, almost 2 in 100 births are twins. While global data has shown that the rate of multiple births has gradually increased since the 1980s, with factors such as fertility treatments and women starting their families later on in life contributing to this, new figures present a stark change.

Information from a Senior Parliamentary Researcher found that while the number of IVF treatment cycles grew during 2009-2019 in Ireland, there was a 10.6% drop between 2019 and 2020, most likely associated with pandemic-related disruption.

What’s more, the total number of embryos transferred in 2020 was 21% less than in 2019, again believed to be caused by Covid-19 pandemic-related restrictions.

Changing approaches with regards to how many embryos are transferred to the uterus of a patient during IVF could also be a reason for the dropping rates. Since 2000, some experts have discouraged multiple embryo transfers in a bid to prevent risky pregnancies, again impacting the likelihood of multiple births.

What makes a twin?

A person can be considered a twin if they were formed alongside their sibling in the womb during a single pregnancy.

Many people will have heard about identical and fraternal (non-identical) twins.

Fraternal or non-identical (dizygotic) twins are the most common twin type worldwide and are formed when two separate eggs are fertilised by separate sperm. The fertilised eggs then implant in the uterus, resulting in two babies from the same pregnancy. Non-identical twins can be the same sex, or different sexes (one boy and one girl).

However, identical (monozygotic) twins will always be the same sex, as they are formed when a single fertilised egg splits, creating two embryos that share near-identical genes.

A twin DNA test – also called a zygosity test – is a DNA test that can be used to determine whether multiple children from the same birth (twins, triplets, quadruplets etc.) are identical or non-identical.

Why might you want a twin DNA test?

There are many reasons why you might want to order a Twin DNA Test.

Examples include:

  • It wasn’t clear during pregnancy (in utero) whether the twins were identical or non-identical. Identical twins do not always share the same placenta and sac – it all depends on when the egg splits
  • You want to assess the likelihood of conceiving twins again
  • One sibling has been affected by an illness, and you want to know whether you need to test the other sibling for the same condition
  • You need the information to take part in a study about multiple births
  • You want to buy a Twin DNA Test as a gift for multiple birth parents or their children

Where can I buy a Twin DNA test?

Thanks to advances in modern scientific techniques, it’s never been easier to find out for sure whether twins are identical or not.

For just €139 and with results in 2-3 days, our home Twin DNA test can be ordered quickly and easily online and gives families the expert answers they need from our award-winning and accredited laboratory.

With only simple cheek swabs required, this easy and completely painless test can be used on siblings of any age – from new-born babies to grown adults. The DNA (zygosity) certificate provided on completion of the test can also be used as a unique keepsake for multiple birth parents.

Need to know more about our Twin DNA test? Call our friendly and knowledgeable Customer Services team on 0140 29466 or email them at

Identical or non-identical?

Order Ireland’s fastest, most conclusive Twin DNA test, direct from our accredited laboratory.