A B.C. couple who have been fighting to bring their surrogate-born twins home from Mexico have been issued birth certificates for the premature babies.

Greg and Elaine Smith's twins were born prematurely earlier this month after using a paid surrogacy clinic in Mexico. The Smiths are now trying to bring the babies back to Vancouver to receive care at B.C. Children's Hospital.

Greg's aunt Linda Pruden said the couple has just cleared one hurdle.

"We heard last night that they had the birth certificates," Pruden told The Early Edition's Rick Cluff.

The twins were born on Jan. 8 at just 31 weeks. 

The Smiths now face more than $100,000 in medical bills, according to a crowdfunding site set up by extended family. Both babies are on respirators after their lungs stopped working, which is a common complication with premature babies. Ariana has also suffered several infections and a serious brain bleed, said Pruden.

Now that the couple has birth certificates for the babies, they need to go to the Canadian embassy to get the twins Canadian passports.

Pruden said baby Ayden should be well enough to travel within a few days, but his twin Ariana is still in critical condition. She said the Smiths will stay in Mexico until Ariana can travel before making the trip home.

To hear the full interview with Linda Pruden, click the audio labelled: Surrogate-born babies get birth certificates.