Seventeen, pregnant and unmarried: Palin's girl becomes an election issue

The sudden intrusion of adolescent bedroom drama into the US presidential race threatens to rock, if not quite capsize, the nascent McCain-Palin ticket. Sarah Palin, the vice-presidential nominee, astonished Republican delegates assembled in St Paul for their truncated convention yesterday by announcing that her 17-year-old daughter, Bristol, is pregnant.

The revelation was an effort to extinguish tawdry internet rumours about who is the real mother of the Alaska Governor's fifth child born in April this year. Left-wing blogger sites, including the prominent Daily Kos, had been speculating that Mrs Palin's fifth child, Trig, who was born earlier this year and diagnosed with Down's syndrome, was in fact carried by Bristol, who would have then been 16. The implication was that Mrs Palin, a social conservative, claimed the baby as her own to cover up for Bristol's indiscretion.

It was partly to thwart those rumours that – barely hours after conservative Republicans were tripping over one another to hail her place on the ticket as a stroke of genius – Mrs Palin made her statement that Bristol was five months pregnant and will marry the father and keep the child.

Even before yesterday's surprise, fears were already creeping in that Mr McCain's choice of running mate, although it sent a shot of electricity through the conservative base of the party, could be more of a liability than an asset.

Mrs Palin made no public appearances in St Paul yesterday as she ostensibly introduced herself to party stalwarts in private meetings and put the final touches to her acceptance speech scheduled for tomorrow evening.

Her absence from the stage prompted some to wonder if aides wanted to keep her away from the media glare as an assortment of unflattering stories and headlines began to appear.

The announcement of Bristol's pregnancy came after Mrs Palin's children and her husband, Todd, who works for BP, had landed back in Alaska, beyond the reach of political journalists gathered in St Paul. The statement was issued by the Governor and Mr Palin jointly.

"We have been blessed with five wonderful children who we love with all our heart and mean everything to us," the statement said. "Our beautiful daughter Bristol came to us with news that as parents we knew would make her grow up faster than we had ever planned. As Bristol faces the responsibilities of adulthood, she knows she has our unconditional love and support."

The original postings on the Daily Kos purported to have evidence that the Governor was never pregnant with Trig, including photographs that seem to show her displaying no visible signs of being pregnant and others with Bristol showing, by contrast, a bump on her tummy.

Mr McCain's aides insisted yesterday he was aware of Bristol's pregnancy when he picked her mother last week and the decision to release the news yesterday was precisely designed to rebut the "mud-slinging and the lies".

It is hardly the first time that a nominee has had to cope with embarrassments coming from others in their family. Nor was it clear last night whether the news of such early motherhood for Bristol will appal conservative voters or appeal to them. She did not, after all, elect to abort.

The impression persists, meanwhile, that because Governor Palin only emerged as a serious contender for the vice-presidency in the final days of the search process last week, the normal vetting procedures may have been somewhat shortened and there are more rough edges to her than the McCain team realise. As reporters converge on Anchorage to root through Mrs Palin's political (if not personal) past, there is the potential for more substantial trouble.

Being highlighted already, for instance, is the role Mrs Palin played in encouraging her state to sue the US Interior Department after it placed polar bears on the endangered species act. She doesn't think they are endangered. "Adding them to the list is the wrong move," she said, because "there is insufficient evidence that polar bears are in danger of becoming extinct within the foreseeable future." That and her enthusiasm for drilling for oil almost anywhere could obscure Mr McCain's claim to be environmentally sensitive.

It could be, however, that her "clean-hands" reputation for challenging cronyism and corruption in Alaska which has been cited as one of the main qualities that appealed to Mr McCain, is about to be severely compromised by allegations surrounding the recent firing of Alaska's public safety commissioner.

Admittedly, it is a slightly obscure scandal, known locally as "Troopergate", involving charges that Mrs Palin sacked the commissioner, Walt Monegan, after he failed to respond to requests that he fire a state trooper who was divorced from Mrs Palin's sister. The state legislature has taken it seriously enough to hire an outside investigator.

Mrs Palin, 44, has declared herself innocent and the McCain camp is portraying the investigation as a small local irritant. "The bottom line is Governor Palin has a proven record championing transparency in government and we are confident in that," said a spokeswoman Maria Comella.

Some Democrats – and a few Republicans – think otherwise. "With this appointment, you've given an obscure investigation more national limelight than any grand jury," noted the Democratic consultant Dane Strother. "If they come down on her, what is McCain going to do?"