According to the Sydney Morning Frontier, a phenomenon known as the lost Girl could affect Australia. Studies of more than a million babies show that some parents use abortion on female fetuses or go abroad to choose embryos to give birth to their sons.
As a result of natural fertility, 105 boys will come to the world for every 100 girls born.
But researchers say "systematic discrimination against women begins in the womb," with 122 to 125 boys born for every 100 girls born in some key immigrant communities.
Kristina Edvardsson, a researcher at the University of La Trobe, said that although Australian law forbids people to choose the sex of their children (except for medical reasons), gender discrimination still exists in Australia.
"We have found that some women may choose to terminate pregnancy after they find out they are pregnant with a girl. In other cases, they will go overseas to obtain non-medical sex selection services through assisted reproduction. "
An analysis of nearly 1.2 million infants in Victoria between 1999 and 2015 found that the overall proportion of boys and girls was similar (nearly 105 to 100), with notable exceptions.
Between 2011 and 2015, the ratio of boys to girls among Chinese mothers was 108 to 100. If they had two or more children, they were more biased against men, with a ratio of nearly 125 boys to 100 girls.
Similarly, the ratio of boys to girls born to first-born Indian mothers was 104 to 100, while the ratio of second-born boys to girls jumped to 122 to 100.
The proportion of boys and girls in Southeast Asian countries is also higher than expected.
Dr. Gurdip Aurora, a Melbourne doctor and president of the Institute of India's Victoria State, said he had recently encountered a case of gender selection, linked to a couple who emigrated from India to Australia.
The two had three daughters, and the woman was pregnant again.
"they want an ultrasound, and if they're a daughter, they have to decide if they want the baby."
But doctors refused to provide the help, but he said she was no longer pregnant when he saw the mother again six months later.
"I asked her, and she said we had miscarried our holiday in India. I'm pretty sure it's a girl. They chose abortion. "
There are now available ultrasound technologies around the world to determine the sex of babies. Australian parents can use the new blood test to determine the sex of the baby within 10 weeks.
In India, Aurora attributes the preference for baby boys to the illegal dowry system. Indian girls are forced to hand over large amounts of cash, goods or houses when they marry.
India's government estimates that every year, 2 million girls disappear in India because sex-selective abortions have other forms of discrimination that lead to premature deaths.
But this bias does not exist among all immigrants, and Aurora argues that gender selection is not a major problem for Australian-born Indian communities.
Edvardsson said that after some immigrants arrived in Australia, they had small families, which meant they were more likely to have a son through gender selection, because it was not a viable option to have children until they had them.
Sex selection through test-tube babies is prohibited in Australia unless the child's sex may help avoid genetic abnormalities or the spread of disease.
But there are also companies that offer test-tube-based sex choices to Australian families who go overseas. Abortion providers may not know if a woman is terminating her pregnancy because she wants to have a son.
The desire to give birth to a particular sex is not limited to a particular group, and many reproductive service providers have called for government to allow for gender selection, also to balance the family.
Jim Tasltas, a clinic director at IVF in Melbourne, said that after parents already had two or more people of the same sex, the authorities could support the use of gender selection techniques.
Researchers will begin to investigate the causes and prevalence of gender selection.