Rare twins born with their umbilical cords twisted tightly together are overcoming the odds in the Royal Brisbane and Women's Hospital.
The likelihood of such a pregnancy is one in 10,000.
Jenna and Jennise Tan are only 24 days old but they have already faced a mighty fight.
Their mum's first pregnancy scan at 12 weeks marked the start of a complex journey.
“[It] turned out that it was twins. Two heartbeats and it was a big surprise for us,” their dad, Glenn Tan, said.
About a week after conception, the egg split to create monoamniotic twins, which is one stage before conjoined twins.
Dr Renuka Sekar from the Maternal and Fetal Medicine Unit at RBWH said: “They split after the amniotic sac is formed, basically, so they have one placenta and one sac".
"They have two umbilical cords in that same sac”.
Sharing that chamber meant their umbilical cords became entangled, but they had good blood flow and were born via C-section at 32 weeks.
"I think the moment we heard them cry was like, oh, it was so happy,” mum Joanne Lim said.
The chance of survival for monoamniotic twins is gradually getting better. With proper care, monitoring and technology improvements, it is now well above 90 per cent.
The babies are now breathing on their own and should be able to leave in a couple of weeks.
“I think what we need them to do is show they can gain weight, maintain their own body temperature and get a little bit bigger,” Acting Director of Neonatology at RBWH Pieter Koorts said.
Glenn and Joanne have two more daughters, aged 4 and 7, waiting for their little sisters to come home.
“I am outnumbered, might set up a netball team or something,” Mr Tan said, laughing.
But having more children is now off the cards for the couple.
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