Sue Axon, 51, a single parent of five children from Wythenshawe, Manchester, is challenging Department of Health guidelines that allow health professionals to give sexual health advice to under-16s without parental knowledge or consent.
In a case with wide implications, Ms Axon said the guidance was "undermining" family life by fostering a "culture of secrecy."
She urged a judge to declare that parents should be told before their children were provided with advice about contraception or abortion or treatment for sexually transmitted diseases, apart from in exceptional cases, so that they could play their legitimate role as parents and help them make "wise" decisions. "I find the prospect that my daughters could be receiving contraception and an abortion without my knowledge horrifying," she said.
Lawyers for the Secretary of State for Health, Patricia Hewitt, are defending the July 2004 guidelines, saying the right of confidentiality enjoyed by under-16s is crucial in the battle to reduce teenage pregnancies and improve sexual health.
In a written statement, Mrs Axon, who has two teenage daughters who she has admitted do not share her views, told the judge she had an abortion at the age of 30 which caused her "guilt, shame and depression for many years" and which she still regretted. She said she hoped neither of her daughters "will have to undergo such an experience without at least their mother being present to guide and support them".
She said: "I cannot understand how a doctor could consider such a significant operation to be in their best interests without even consulting me, when an understanding of the child's family context and values would be a significant factor in helping the child through the trauma of either abortion or teenage pregnancy.
"Nor can I understand how effective aftercare could be provided in such a culture of secrecy."
Mrs Axon is challenging government guidance that replaced the "Gillick ruling" by the House of Lords in 1986 which said health professionals were justified in giving contraceptive advice and treatment without parental knowledge or consent, provided certain conditions were met.
She argues the new guidance "misinterprets and subverts" the Gillick ruling and is, therefore, unlawful.
Lawyers for Ms Hewitt, said Ms Axon's criticisms were misplaced and that the rights of the child are paramount in both human rights and common law.
They said that Britain has the highest rate of teenage conceptions and teenage births in western Europe and a parental right to know would discourage young people from seeking advice, leading to greater numbers of teenage pregnancies and higher rates of sexually transmitted infections.
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