Freeze method brings fertility hope

Couples in Ireland unable to have babies naturally have been given fresh hope following the first birth here through a pioneering assisted reproduction technique that increases the chances of expectant mothers.

In the current edition of the Irish Medical Journal, the Human Assisted Reproduction Ireland unit at the Rotunda Hospital reported the first delivery of a healthy child through the assistance of the new technique, which is called vitrification.

According to Edgar Mocanu, consultant gynaecologist and lead clinician at HARI, there is much cause to celebrate the birth of the baby boy through vitrification.

“It shows that vitrification works in our hands, that a healthy child is born, and in general the technique makes the survival of frozen embryos more likely, thus resulting in more pregnancies,” said Dr Mocanu.

The technique offers particular hope for couples where cancer has been diagnosed, requiring the woman’s eggs to be frozen before she undergoes chemotherapy.

Dr Mocanu said vitrification “should offer a better, future chance to conceive after life-saving cancer treatment”.

In the case reported in the IMJ, it concerns a couple, each aged 32, who were referred to HARI. The couple had a history of secondary sub-fertility over the previous three years, which included going abroad twice for treatment that resulted in no viable pregnancy.

The report also records that the father in the case had a history of testicular cancer that resulted in the removal of one of his testicles.

The vitrification method involves the freezing of embryos after assisted reproduction techniques.

Dr Mocanu said: “To date, the so-called ‘slow-freeze’ technique was used when embryos were slowly cooled to -196ºC and then stored for future use.

“The survival of embryos after thaw was only 75%. Vitrification involved the fast or snap freeze of embryos, eliminating the formation of ice crystals, and thus facilitating a much higher embryo survival rate of 95%.

“This ensures that couples consenting to have their embryos frozen have a much higher chance to have their embryos surviving after thaw if this technique is used.”

The consultant stated that “vitrification improves embryo thaw survival rates and offers a better chance of pregnancy than the old, slow-freeze technique”.

Dr Mocanu said that the vitrification method would also facilitate the transfer of one embryo in day five of development, “thus reducing the risk of a multiple pregnancy with its related significant complications for mother and child and significant cost reduction to the paediatric service due to reducing prematurity and intensive neo-natal care”.