A lesbian woman felt violated and devastated when she learned she was pregnant with twins, after she had told a Canberra obstetrician she wanted only one child through IVF, a court heard yesterday.

In what is believed to be the first case of its kind in the ACT, the former Canberra woman and her female partner are suing obstetrician and gynaecologist Sydney Robert Armellin for the wrongful birth of one of their twin girls, now aged three, claiming more than $400,000 for the cost of raising her to the age 21.

They claim the twins' birth mother had told Dr Armellin minutes before she was sedated and implanted with two embryos that she wanted only one embryo implanted. They had previously told him they wanted only one child.

However, an embryologist under Dr Armellin's supervision implanted two embryos, resulting in the birth of non-identical twins.

The birth mother, now working in Melbourne as a social research and planning consultant, wept as she told the ACT Supreme Court how hard it had been to cope with the unplanned twin pregnancy.

"I remember sitting on the couch and feeling devastated, absolutely devastated," the 40-year-old mother said.

She and her partner, who were living in Watson at the time, had planned to go to England after the birth, but their plans were scrapped when they discovered they would be having twins, jeopardising their careers, relationship and health.

She suffered pre- and post-natal depression, could work only a few hours at a time because of the pain, and she and her partner needed relationship counselling for about 18 months.

"We argued and we had a terrible time with the stress of what we had expected to be a time of great joy."

They also had to confront the options of aborting one of the embryos, or giving up one of the children for adoption. They decided to keep both children as an abortion would have put the other child at risk, and adoption would have been too painful.

"The experience of my pregnancy was so far removed from what I had anticipated that I was in relationship counselling, in a great deal of pain, and someone was suggesting that [adoption] was an option."

The women's names were suppressed until today, when visiting judge Justice Annabel Bennett will make a ruling as to whether to permanently conceal their identities.

The women's barrister, Hugh Marshall, SC, argued it could be distressing for the children to discover several years down the track that their mothers did not want to have them both.

The birth mother told the court she earned more than $100,000 in the recent financial year, and her partner also worked full time.

They had first gone to Dr Armellin, who has a private practice in Deakin and also does work for John James Hospital and Calvary Hospital in December 2002, seeking artificial insemination treatment. They chose to use sperm from a Danish donor, as the father of one of the women was German.

After three unsuccessful treatments of artificial insemination, Dr Armellin recommended in-vitro fertilisation.

The mother told the court she and her partner had told Dr Armellin and a nurse at the Canberra Fertility Centre that they wanted only one child.

However, they had been under the impression that they could only decide how many embryos to implant on the day of the procedure, depending on the quality of the embryos.

They had signed a pre-admission form two months before the procedure, saying they consented to one or two embryos being implanted, but claimed the nurse at the fertility centre had said: "Just put 'up to two' and you can let us know any time up to the procedure."

Consequently, the mother had told Dr Armellin she only wanted one embryo implanted only minutes before she was sedated, in November 2003.

As well as seeking damages for the cost of raising a child, the birth mother is claiming about $17,000 for lost earnings as a result of an extra two months' maternity leave, and for the physical problems and medical expenses incurred as a result of carrying twins. She was rendered almost immobile in the second and third trimesters of the pregnancy.

Dr Armellin's barrister, Kim Burke, told the court her client admitted being told by the birth mother shortly before the procedure that she wanted only one embryo implanted, but this did not amount to negligence.

"The defendant's position is that the duty of care did not extend to preventing or avoiding multiple births," Ms Burke said.

"The conversation [minutes before the procedure] is not a negligent act because there was a document signed saying one to two embryos."