A young family has welcomed four identical baby girls in a birth so rare doctors believe it may be the first naturally conceived pregnancy of its kind in Australia.

The quadruplets — Emily, Harriet, Alexa and Catherine — were born at the Royal Brisbane and Women’s Hospital (RBWH) on July 14 after an extremely high-risk pregnancy.

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The girls were delivered by elective caesarean section at 28 weeks and four days and are now receiving specialist care in the hospital’s neonatal intensive care unit.

Mother Jenitar Na’amoana, 34, and her husband, Jortham, are now adjusting to life as a family of 10 after the arrival of the quadruplets, who join siblings aged 10, 8, 3 and 1.

Jenitar and Jortham Na’amoana with their four older children before welcoming the quadruplets. Credit: Facebook

The identical quadruplet girls are receiving specialist care in the Royal Brisbane and Women’s Hospital neonatal intensive care unit. Credit: RBWH

The family has launched a GoFundMe campaign, saying they urgently need a larger 10- or 12-seat van, baby equipment and help with ongoing medical, travel and everyday living expenses.

“Our four precious miracles have arrived safely, and while our hearts are overflowing with gratitude, the reality of caring for four newborns at once has brought challenges we never could have imagined,” Jenitar wrote.

RBWH maternal fetal medicine specialist and obstetrician Dr Alexa Bendall said the birth was extraordinarily rare.

“They are very special,” she said.

“They have come from one fertilised egg, that has split four times, to end up with four identical girls.

“There was only about 100 grams between all of them, which is incredible.” 

The pregnancy was considered extremely high risk because the identical quadruplets shared one placenta. Credit: GoFundMe

Jenitar and Jortham Na’amoana are now parents to eight children after welcoming the rare quadruplets. Credit: Facebook

Bendall said spontaneously conceived identical quadruplets are estimated to occur in around one in 15 million pregnancies.

“We don’t think it’s ever happened in Australia,” she said.

“There may have been a couple of cases elsewhere in the world.”

The four girls shared a single placenta but each developed in their own amniotic sac, making the pregnancy particularly complex.

“It is a very, very high-risk pregnancy,” Bendall said.

“There is a high risk of mortality and morbidity for these babies, and for mum.”

The family was surprised when they found out they were having four babies instead of one.

“Jenitar already had four babies at home, including one that she was breastfeeding at the time.,” Bendall said.

“When they went along and they found out that they had four babies instead of one, they were quite shocked.”

Jenitar was admitted to hospital at about 25 weeks after developing a short cervix and early contractions.

“We always said that if we could get her to 28 weeks, we would be doing well,” Bendall said.

“The fact that we’ve got four beautiful, healthy babies born at 28 weeks and four days is incredible.”

Dr Alexa Bendall says the naturally conceived identical quadruplets are among the rarest births in the world. Credit: RBWH

Jenitar Na’amoana shared an emotional update after welcoming her four identical daughters. Credit: Facebook

The babies were delivered in good condition and are expected to remain in the neonatal intensive care unit for several weeks while they grow stronger.

“Long term, their outlook will be really good,” Bendall said.

She said she felt honoured one of the girls, Alexa, was named after her after helping guide the family through the high-risk pregnancy.

Bendall said the birth required the usual caesarean section team, along with an additional three neonatal teams to care for each of the four babies immediately after birth.

“We’re all very privileged to be a part of it,” she said.