Canada might not have enough sperm donors without turning to other countries, a new report on the country's ban on paying donors suggests.

The federal government banned the sale of human eggs and sperm under Canada's Assisted Human Reproductive Act in 2004.

Since then, there's been a gap in implementing the ban and current practice allows payments to sperm donors from the U.S. and Europe, said the report's lead author, Dr. Edward Hughes of the Department of Obstetrics and Gynecology at McMaster University in Hamilton.

"It's important to look at our situation, because the law mandates an altruistic system," Hughes said Tuesday.

"My take on this is that altruistic sperm and egg donation is the ethically sound model to use. The practicalities are though, that [in vito ] treatments are expensive and intensive and require an infrastructure and regulation. Infrastructure and regulation are the two things right now that need to be defined, refined and built."

Currently, women and same sex couples using donors have a selection of around 200 sperm donors, the report concluded. Of these, less than 40 are Canadian, and the rest are paid since they are outside of the country, Hughes' team estimated.

"The agency did not commission a report on the feasibility of altruistic donation," said Emmanuelle Gallays, a spokesperson for Assisted Human Reproduction Canada.

"Rather, it commissioned a report and modelling tool, Altruistic Sperm Donation in Canada: an Iterative Population-Based Analysis, to better understand the dynamics of altruistic sperm donation in Canada," she added in an email.

The report offers the agency information before it can move toward implementing the payment-free or altruistic system, Hughes said.

For the altruistic or non-payment model to work, Canadians need to be educated about the need for sperm donation and how it works, just as there are awareness campaigns for blood and tissue donation, Hughes said.

The aim is for patients to continue to meet their fertility goals safely and effectively, Hughes said, adding he's found a lot of interest in the topic, and he welcomes the discussion.

The agency's efforts to implement the act were delayed until last December's Supreme Court of Canada ruling  that the act infringes on provincial jurisdiction for some forms of assisted human reproduction,

The top court's split decision allows provinces to regulate health aspects of fertility clinics including in-vitro fertilization. The ban on purchase of sperm, eggs, embryos or surrogacy services remains.

With files from CBC's Amina Zafar