An investigation has found that a hospital in Sichuan province neglected its duty when it failed to inform a pregnant woman she had tested positive for HIV and syphilis.

The mother, identified only as Zeng for privacy reasons, first learned of the diagnosis the day after she delivered her daughter at Yibin Women's and Children's Hospital on Feb 21.

She was also told that, as she had received no treatment or interventive medicine during pregnancy, the conditions may have been transmitted to her child.

Yibin health and family planning commission said in a statement late on Monday that a probe had concluded that the hospital had neglected its duty, and pledged tough penalties for those responsible.

Zeng had a prenatal checkup at the hospital in July that included tests for syphilis, HIV and hepatitis B.

"No one told me I had syphilis and was HIV positive after the checkup," she said, adding that she also had monthly postnatal checks between July and January.

Doctors admitted Zeng to hospital on Feb 20 and prepared her for a caesarean section. "On Feb 21, my daughter was born," she said. "The next day, I was told she had syphilis and may be HIV positive. I was shocked."

Liu Xiaowei, head of obstetrics and gynecology at the hospital, said doctor Liu Renhui, who conducted the initial HIV and syphilis tests, had attempted to call Zeng and her husband after receiving the results, but no one answered.

When Zeng received pregnancy checkups at the hospital in the following months, she saw three different doctors.

The commission said on Monday that the hospital had failed to strictly implement regulations that aim to prevent mother-to-baby transmission of HIV/AIDS and syphilis, and that there were problems with its management.

Medics with the obstetrics department also "lacked a sense of responsibility", the statement said, adding that Yibin's health enforcement and inspection team had filed a case and will investigate further.

The child, who has remained hospitalized, will receive further tests in seven days, according to a report by The Paper, a Shanghai-based news website, which cited a health commission official as saying HIV tests for newborns are only possible after 42 days.

A campaign will now be carried out at all medical institutes in Yibin to prevent similar cases from happening, the commission's statement added.