Amy McDonald's first reaction to discovering she was pregnant was panic, she admits.

"I had plans to have a career and go to university. And there was the question 'what will my mum and dad think'."

At 17 now, with an 11-month-old son Sean, the Glasgow schoolgirl is managing to buck the stereotype, however. While juggling her lessons and parenting, she's still planning to go to university, next year, and aiming to study nursing. Her parents, after their initial shock, are supportive.

There's no doubt she's also been helped in that by the availability of the city's Young Parents' Support Base (YPSB), located at Smithycroft Secondary in Glasgow's Riddrie. The base currently supports 31 teenaged mums from across the city to stay in education, including 10 like Amy, who study at Smithycroft.

"If I hadn't come here I would have dropped out of education," she says. "You get a lot of help with parenting skills, as well as keeping your subjects going. It's a hard balance."

The school has converted a former staff conference room into a well-equipped nursery, and also offers a range of out-of-school support groups for young parents – including some dads – covering a range of issues from parenting skills and smoking cessation to sexual and relationships education.

Pupils at Smithycroft can leave their babies in the base while attending lessons and most follow a reduced timetable. They generally drop one to three subjects, leaving time for supported parenting sessions with their babies, and study time during the school day which makes up for the fact that they might otherwise be unable to manage home work and coursework in the evenings.

"I get to see Sean here. At first I felt I was missing time with him while I was doing my school work, but it's good because you get to step away and have time to be teenagers," Amy says, acknowledging that being around other young mums is a help.

Smithycroft Secondary was visited by members of the Health and Sport Committee last month, as part of its members' current inquiry into teenage pregnancy. MSPs on the committee are looking at what more can be done to reduce unplanned teenage pregnancies and help those who do become pregnant at a young age.

Interestingly, the young women whom MSPs met at the base were not inclined to describe their circumstances as a problem. However, Amy, who is still in a relationship with Sean's 20-year-old father, is in a minority. "We're still together and he's a really good dad. He takes Sean out at weekends and I think some of the other mums are a bit envious of that," she says. "But it isn't easy. You have to put a lot more into a relationship when you have a baby."

It is already clear that the nature of the "problem" of teenage pregnancy is likely to be a significant part of the committee's inquiries.

Like the young mums at Smithycroft, teenage parents surveyed by Fife Gingerbread as part of its written response to the committee were not ready to concede this point. "They did not feel that being a teenage parent was necessarily a bad thing that should be reduced," support worker Louse Morris explained. "[They thought] the government should be seeking to reduce the number of families relying on benefits rather than specifically the number of teen pregnancies."

The British Medical Association's submission to MSPs pointed out that there was no biological reason why having a baby before 20 should be associated with ill health. In fact, its spokeswoman point out, it is the other way round – older mothers face a higher risk of complications in pregnancy.

But, the doctors' body added, social and economic exclusion are a problem, and their effect on the health of mothers and babies of all ages is a worry. Teenage pregnancy can make that worse, by interfering with an adolescent's education. "High teenage pregnancy rates are linked to high levels of social exclusion," the BMA adds.

Many experts seem to be agreed that levels of education, opportunity and expectation are a key issue in determining whether young people, by accident or by design, start a family at a young age. Giving evidence to the inquiry, Ann Eriksen, of NHS Tayside, gave a more rounded picture of the circumstance for local families. "For the young women who said they wanted to be pregnant and wanted a baby, it was very much about looking for love and affection and looking for someone whom they could love unconditionally and who would love them in return... Some young women might not see educational attainment or employment as providing that status, so it almost seems that having a baby means being recognised as moving into adulthood."

In a thought-provoking written contribution to the inquiry, Jonathan Sher, Scotland director of the Wave Trust, urged MSPs to be clear about what they were trying to prevent. Rather than preventing all teenage pregnancies, they could be clear, he suggested, about their targets: preventing, for instance, pregnancies which might otherwise end in terminations, preventing them where the parents have "diminished capacity", preventing foetal alcohol harm, or preventing the marginalisation of teenaged dads, for example.

For some, Mr Sher adds, pregnancy at a young age is a positive and intentional choice. "Good young parents are not rare. Our knowledge of young carers in Scotland should also serve as a reminder of the reality thatage is not the sole, or even primary, determinant of one's ability to love, nurture and take responsibility within a family."

It is clear that while some teenaged pregnancies may be positive, in other cases they are a potentially life-changing mistake, a preventable accident. On behalf of the Scottish sexual health lead clinicians' group, Dr Ruth Holman offered MSPs a challenge. "The Scottish Government is prepared to make a stand on controversial subjects like gay marriage," she said. "Whey does it run scared of its critics on the subject of making emergency contraception available in schools?"

MSPs may be more likely to call for an expansion of access to resources like the YPSB. And that may have a surprising side-effect. "There hasn't been one unplanned pregnancy at Smithycroft since we set up the base," explains Deborah Blackhurst, who played a key role in the project. "Perhaps because other pupils see the reality."

Amy McDonald with son Sean. Sean attends the Young Parents' Support Base nursery at Smithycroft Secondary school while Amy studies.