Simms choking back tears on Friday told about the babies who are joined at the scalp.
She said, 'I just try and keep my head where it has to be, keeping these babies healthy and me healthy and making sure they have a better chance. They each have their own brain but they're sharing most of the main nerves and the arteries.'
Doctors have told Simms that the twins could be delivered by caesarean section when she is 32 weeks into her pregnancy.
Simms, 20, is already a mother to a four-year-old daughter and a two-year-old son.
Simms has been consulting with a team of specialists at Women's Hospital in Vancouver and has planned to make regular trips to the facility during her pregnancy.
Conjoined twins are rare, about one in 200,000 births and those joined at the head are said to make up only two per cent of all conjoined twins.
According to Simms's mother, Louise McKay, three sets of conjoined twins have previously been born in B.C. but that they were joined at the heart and stomach.
She said, "There have never been conjoined twins of this nature to the head."
Erin Toews, a spokeswoman at Women's Hospital, said that the only set of conjoined twins delivered at the hospital was in the 1990s and no surgeries to separate conjoined twins have been performed in the hospital as well.
Simms is on income assistance and the family has set up a trust fund to help pay for her frequent trips to Vancouver.
NDP health critic Adrian Dix has said that Health Minister George Abbott should consider pitching in to help Simms pay for some of her costs.
He said,"I'm hopeful the minister will look at this issue, look at the challenges facing this young mother in terms of not just the children she's carrying but her other children and provide some assistance so that she doesn't have to organize a major fundraising effort just to get basic health care."
Helen Simeon, a spokeswoman at the Hospital for Sick Children in Toronto, claimed that the facility has performed surgeries to separate 10 sets of conjoined twins since 1966, the last of which was done in March 2005, when a team of doctors successfully separated twin boys from Zimbabwe, Tinashe and Tinotenda, joined at the stomach and liver.