Canadian fertility experts have released guidelines regarding the number of embryos to be transferred during an in vitro fertilization (IVF) cycle. The guidelines were jointly published by the Society of Obstetricians and Gynecologists of Canada and the Canadian Fertility and Andrology Society.

IVF is a very tricky process. In order to increase the likelihood of success, several embryos are transferred to a woman’s uterus. However, this also increases the chances of having a multifetal pregnancy.

The purpose of the guideline is to minimize multiple, especially high-order multiple pregnancies without necessarily lowering the success rate of IVF. The experts based their recommendations on a thorough study of medical articles published between 1990 and April 2006.

In recent years, the rates of multiple births have risen. I am not one to complain. I feel lucky to have had twins. However, multiple pregnancies, especially high-order multiples (e.g. 3 babies or more) can pose risks both for the mothers and the babies.

Here are some of the recommendations:

• 1 fresh embryo for women under 35 years old with “excellent” prognoses and 2 fresh embryos for those with less than excellent prognoses.
• A maximum of 3 embryos for women 29 to 38 years old
• A maximum of 4 embryos for women 39 years old and older.

The guidelines are published in the September 2008 issue of the International Journal of Gynecology & Obstetrics.