A 40-year-old mother who buried her nine dead babies in flowerpots refused to answer charges of manslaughter today as a German court opened hearings in the country’s worst case of infanticide since the war.

Sabine H - whose full name cannot be given for legal reasons - shook her head vigorously when asked to testify at the outset of a trial which is gripping Germany.

Judge Matthias Fuchs then dispassionately read out the extraordinary story of the dental technician who is accused of letting nine of her 13 children die soon after birth.

The shocked court heard how Frau H drank herself into a stupor to still the pain of her secret childbirth. "As a result I can only remember two of the births," said Frau H in testimony given to the police soon after her arrest last summer.

On one occasion, in 1988, she gave birth on a toilet. "I will never forget her blue face and the little drops of foam on her lip," she said in the testimony read out in court today.

A second birth, in 1992, was in a hotel room in the town of Goslar. A colleague entered the room shortly after the birth and Frau H promptly covered herself with a blanket and stuffed the baby out of view. It died shortly afterwards.

The two dead babies were buried first in flowerpots on her balcony in Frankfurt on Oder, near the Polish border. As she gave birth on an almost yearly basis, other baby corpses started to fill up the plant pots.

Eventually Frau H decided to take them all to her mother’s house in a small village south of Frankfurt. There they were discovered last year by a relative who wanted to use an abandoned aquarium tank stored in the garage. He tipped out the sand and found a skull.

The case has been troubling Germany ever since. Demonstrators outside the courtroom today held up placards saying "tell the truth!" and "we mourn nine little children".

Why were her many pregnancies not noticed by neighbours? How could her ex-husband - father of all the dead children, according to DNA tests - not have registered her condition?

"I thought she had a weight problem," said the husband Oliver H, in an early police interrogation. Today he too refused to answer questions in the courtroom. Politicians have been arguing how a woman in need can fall unnoticed through Germany’s elaborate social welfare network.

One leading conservative, Joerg Schoenbohm, courted controversy by suggesting that East German society had been brutalised by so many decades of communist rule. Three times as many babies had been found dead in Eastern Germany than in the West over the past decade.

Frau H’s said her husband did not want more children, so she had to hide her pregnancies to save her relationship. She has confessed to the two early deaths. The 1988 death can no longer be prosecuted: it falls under the statute of limitations for manslaughter.

If found guilty of causing the death of the second child, Frau H could expect only a mild sentence. The maximum sentence could be 15 years jail. Frau H has been recently diagnosed with cancer and this will probably be taken into consideration.

Frau H, as far as the German public is concerned, remains a mystery: a highly intelligent woman, vivacious and a good mother to her three first children who are all well adjusted young adults.

Somehow, from 1988, she entered a pattern of concealed childbirth. "I would sit on the balcony and talk to them in the flowerpots," she said. Mysterious too is the reaction of the villagers who saw nothing and said nothing. Then there is the question of how and why Frau H snapped out of her behaviour. She had a final child - her 13th - with a new boyfriend. The child is two-years-old, alive and well.

Times Recommends

• Mandela’s tribe threatens President Zuma
• The French empire strikes back
• Wife of cheating governor exacts a political revenge