Single women in their late 30s are increasingly giving up waiting for "Mr Right", instead turning to IVF or assisted reproductive technology to have a baby on their own.
IVF clinics in Sydney and Melbourne have reported that the number of women using donor sperm to conceive a child has jumped 10 per cent over the past three years.
According to IVF Australia fertility specialist Michael Chapman, while lesbian couples account for some of the increase, the real growth is occurring with older, single heterosexual women.
"We're seeing more and more of these ladies - women who can't find Mr Right but who still want a child realise this is an option," Professor Chapman said.
"It's become almost normal to be a single mum. So when these women get to 38, 39, they go to donor sperm and do assisted reproduction."
Women who can't find Mr Right but who still want a child realise this is an option
Categorised by the IVF industry as "socially infertile", these women rely on their mother, sister or a friend to support them through the IVF process in the absence of a partner.
However, some sperm donors are refusing to let their sperm be used by this group of women, concerned for the welfare of a child raised without a father.
"Many sperm donors are not comfortable giving sperm to single women and lesbian couples," Professor Chapman said. "There is a desperate lack of men who are prepared to give into that environment."
More generally, sperm supplies have fallen since donors lost their anonymity in 2010. NSW law dictates one man can father only five families, while in Victoria a sperm donor can father 10 families.
Gab Kovacs, from Monash IVF, said his single patients were usually successful women in careers such as banking or journalism. "They're financially able to support a child on their own," he said.
One mum's story
Sydney woman Natalie Hayden put down her name for donor sperm when she was 34 as a "back-up plan" if the relationship she was in didn't work out.
A donor became available when Ms Hayden was 36, but she delayed IVF another year to get more financially secure, saying "I didn't do it until I could control the situation financially".
It took six cycles and about $17,500 (after the Medicare rebate) to fall pregnant, but Ms Hayden said it was "worth every cent" to get her son, Lucas, who is now nearly two.
Although Ms Hayden worried what some people would think of her decision to go it alone, her friends, family and employers were very supportive.
She hopes Lucas will one day be able to meet his biological father.
"If I do meet somebody, it will be a lot easier for them to be accepting of a child when there isn't another parent. Hopefully they'll want this gorgeous little boy in their life."
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