Teen sex is a modern reality. While today's teens easily pick up sexual practices from the Internet and books, they are generally ignorant about the deadlier facts.

For instance, sexually active girls below 15 years are more prone to diseases like the human papillomavirus (HPV) and cervical cancer.

Even in supposedly conservative Singapore, the number of sexually transmitted infections (STIs) among teenagers last year hit a high of 820, up from 775 in 2006, according to the Ministry of Health.

In addition, there were 833 pregnancies in girls 19 years and under last year, 16 of whom were below 15 years old. There were also 1,363 teenage abortions.

Professor Kuldip Singh, senior consultant at the department of obstetrics and gynaecology at the National University Hospital, said: 'Now, with mass media like the Internet, teenagers are being exposed to sex and sexual activities at an increasingly younger age.'

Others point to delayed marriage and relaxed attitudes for the higher numbers of teen sex.

Among the teens themselves, Sheryl (not her real name), 18, a junior college student, said she first had sex when she was 14. She added: 'Teens are now more liberal. We see sex as a personal choice and not a lot of people I know are keeping themselves celibate until marriage.'

Sarah (not her real name), 17, a secondary school student, said: 'It's almost like no one's talking about it but everyone's doing it.'

While parents despair, doctors and others worry about the consequences of teen sex, specifically teenage pregnancy and STIs.

Ms Vanessa von Auer, clinic director of EVA Psychology Centre, said teens often acquire a lot of information from the Internet and books about the practical aspects of sex but don't realise the importance of protecting themselves.

Dr Sadhana Nadarajah, head of the adolescent gynaecology unit and consultant in the reproductive medicine unit at KK Women's and Children's Hospital, said: 'Having sex too early may lead to an unwanted pregnancy and its termination. This may emotionally scar the teenager for life.'

As for STIs, the top four infections diagnosed in youths here aged between 15 and 24 years are chlamydia, gonorrhoea, candidasis and non-gonococcal urethritis.

HPV infections - which can lead to genital warts and cervical cancer - and HIV infection are also possible outcomes.

Sexually active teenagers often catch STIs because they are ignorant about them and about contraception, and also because of peer pressure.

In a survey last year by Bayer Schering Pharma of 600 Singapore youths, it was found that 13 per cent of those between 16 and 23 years old were sexually active. Within this group, 23 per cent did not use contraception.

Earlier this month, Bayer Schering Pharma conducted a similar survey of 233 university students here. In it, 56 students said they had had sex and 17 of these said they did not use contraception.

Human resources executive Carol Tan, 26, who started having sex when she was 15, said of her teenage stance towards contraception and STIs: 'I was too young to realise I should have asked about protection and STIs. It was all about love then.'

Sexual health experts Mind Your Body spoke to said that for youths who are already having sex, combining oral contraceptives with the use of condoms is the best form of protection against STIs and prevention of unwanted pregnancy.

However, some, like Focus On The Family - a charity body dedicated to the strengthening of Singapore families - and Dr Christopher Ng, consultant obstetrician and gynaecologist at GynaeMD Women's & Rejuvenation Clinic, mooted teen abstinence.

Dr Ng said that young people are disproportionately affected by STIs because they are more sexually active, have more sexual partners, tend to have overlapping sexual relationships and are more likely to have casual sexual relationships.

He added: 'Most young people do not use condoms and most have not been taught their correct use.'

Biology plays a role in teenagers being more prone to STIs.

For instance, sexually active girls below 15 years are at greater risk of developing cervical cancer from HPV infections. This is because their cervix and genital tract are just starting to mature.

Professor Margaret Stanley, professor of epithelial biology in the department of pathology at the University of Cambridge, told Mind Your Body that the epithelium (a layer of cells lining the genital tract) in young girls is very thin and quite easily damaged and when that happens, infection can occur.

'Moreover, hormones in a teenage girl are changing all the time and the HPV is very sensitive to hormonal changes. If you're infected and your hormones start to kick in at a ferocious rate, so does the virus,' she added.

Sexually active teens also have to deal with the social and emotional repercussions of their behaviour.

Dr Brian Yeo, consultant psychiatrist at Mount Elizabeth Medical Centre, said: 'Many young people feel coerced into having sex and when they do, they feel they've lost control of their bodies.'

Sex education is needed to equip teenagers with the emotional and psychological tools to deal with sex and its myriad confusions.

Breaking Down Barriers, taught at Secondary 3 level, is a broad-based sex education programme that is disseminated through science, health education and civic classes.

The Ministry of Education will introduce a customised programme which aims to raise awareness of STIs in November.

Some voluntary welfare groups have already taken steps to address the gaps in sex education for teens, conducting talks for youths in school and workshops teaching parents how to talk to their children about sex.

Ms Kelly Lee, programme officer and counsellor at The Singapore Planned Parenthood Association, a voluntary welfare organisation which conducts sex education talks in secondary schools and tertiary institutions, said: 'We believe in giving youths the right to choose. We provide information on sexual health and ask them to consider the consequences of their actions.

'The best choice when you're not ready though is definitely abstinence.'

Ms Tan agreed. She said: 'I started having sex too young.

'I'm fortunate I didn't catch anything or get pregnant. If anything had happened, I wouldn't have been able to cope on my own.'

This article was first published in Mind Your Body, The Straits Times on Sep 18, 2008.

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