IMH said that stress-related, anxiety and depressive disorders are common conditions seen at its Child Guidance Clinics, which treat children aged six to 18.
The clinics saw an average of about 2,400 new cases every year from 2012 to 2017.
Since IMH does not track the causes of the disorders, it does not have statistics on cases related to school stress.
However, Dr Lim Choon Guan, senior consultant and deputy chief of IMH's department of developmental psychiatry, said: "Over the past few years, I have seen more teenagers in our clinic who are from top schools and report experiencing school-related stress."
Replying to The New Paper's queries, Dr Lim said this trend does not necessarily mean more youth are feeling stressed about their studies but suggests they are more willing to seek help.
Dr Lim said school-related stress could be academic-based (homework, examinations, projects) or relationship-linked (issues with school authorities, friendship and bullying).
School stress became a hot topic of online discussion recently after someone who identified herself as a 17-year old International Baccalaureate student in a top school here wrote about her admission to IMH for suicide attempts and a history of depressive episodes.
In her online post, she wrote about facing immense pressure to do well in school and claimed her brother, a junior college student, "killed himself two years ago, partly due to the pressure from my parents to do well".
She claimed to have met in IMH four other students from top schools who had attempted suicide or self-harmed because of school stress.
Experts told TNP that pressures faced by the young are real and can lead to anxiety, depression or suicidal behaviour.
These pressures could come from the home or school environment or, more worryingly, even themselves.
National Institute of Education's Associate Professor Jason Tan said the types and levels of pressure faced by the youth today have increased.
Though the Ministry of Education (MOE) has expanded the university cohort to provide more opportunities, students still face stressors, he added.
"Now it is not just about going to university but also getting into the best courses and prestigious schools," he said.
Citing how the rise of social media has created self-image issues, Prof Tan said: "Now students are not just competing with their classmates or peers, they are exposed to youth around the world."
This may lead them to have unrealistic expectations.
•Samaritans of Singapore: 1800-221-4444
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He added that online bullying is also a major problem.
He said: "Unfortunately, there are not enough safeguards in place. Mental health issues are silent, invisible killers.
"Others unable to understand them or spot the signs may simply tell these youth to snap out of it or stop being lazy. It is difficult to handle, not just for the individuals but for their parents, teachers, classmates and friends," said Prof Tan.
Madam Choy Wai Yin, director of MOE's guidance branch at the student development curriculum division, said: "Issues faced by students include management of emotions, sense of self-worth, motivation, family and peer relationships."
She said such students have access to programmes and people should they need help.
Many schools have implemented a peer support system to motivate students to look out for and encourage one another to seek help from trusted adults.
"While schools can assist the students, support from home and community is also crucial.
"We have stepped up our engagement with parents to raise awareness so they can better understand and support their children's mental health, and provide them with information on where they can seek help if needed," Madam Choy added.