A man who risks being jailed for paying an alleged juvenile prostitute might think it wise to avoid generalisations about the female sex. But not Silvio Berlusconi.

Making a surprise first appearance at the trial arising from his "bunga bunga" parties, Italy's former prime minister delivered his opinion that "girls … women are by nature exhibitionist".

He was speaking to reporters outside a court which had heard earlier this week that two of his young women guests had performed a pole dance while wearing – and subsequently not wearing – nuns' habits. Leaks from the inquiry have also alleged there were stripteases by showgirls in skimpy police uniforms.

Berlusconi confirmed that some of his young female guests at his mansion near Milan had indeed dressed up as policewomen, but only for the purpose of "burlesque games". He insisted that he had hosted "only elegant dinners, and after dinner sometimes we went down to the theatre, my children's former discotheque, where there was an atmosphere of good cheer and affection."

It is the precise extent of the good cheer and affection that is being examined in a case that centres on Berlusconi's relationship with Karima el-Mahroug, a young Moroccan runaway turned dancer. Mahroug, who denies she is or was a prostitute, attended several parties thrown by Berlusconi when she was 17 years old. Paying for the sexual services of anyone under 18 is an offence in Italy.

The former prime minister, who under Italian law is not obliged to attend his trial, made his high-profile appearance on a day when his successor as party leader, Angelino Alfano, revealed they would soon be making an important proclamation. Alfano said the announcement, to be made after local elections on 6 and 7 May, would "change the course of [Italian politics] in the coming years."

Berlusconi also took advantage of his day in court to explain why he had paid large sums of money to some of the women who are due to testify. He said he was giving financial support to all his former guests "because they have had their lives ruined by this trial".

He added: "Some of them have lost their boyfriends, and perhaps they'll never again find another."

This month, it was reported that Berlusconi, one of the world's richest men, had given a total of €127,000 to three women including his former dental hygienist, Nicole Minetti. A regional lawmaker for Berlusconi's party, Minetti is a key figure in the case.

In 2010, when El-Mahroug was detained in Milan, suspected of theft, a senior police official, Piero Ostuni, was telephoned by the then prime minister. "He told me that there was a girl at police headquarters who, he had been informed, was the granddaughter of [the then Egyptian president, Hosni] Mubarak, and that the parliamentarian Nicole Minetti would come and take care of the situation with regard to care," Ostuni said in evidence.

Berlusconi, who is also charged with taking illegal advantage of his official position, denies all wrongdoing. He has insisted he believed the girl really was a relative of the Egyptian leader.

The police officer who questioned El-Mahroug, Giorgia Iafrate, told the court the girl had admitted she was not Mubarak's granddaughter, "but that sometimes she passed herself off as such". Superintendent Iafrate said she had informed Ostuni.

He testified that he had not, however, relayed this information either to his superiors or the prime minister's office. Ostuni told the court he could not explain why he failed to make it clear to Berlusconi's aides that the girl was not related to Mubarak. "Perhaps a doubt remained. At all events, I didn't do so. I didn't think of it."