According to a study conducted by National Institute of Health and Family Welfare, a quarter to a third of India's young people indulge in premarital sex.

A majority of the 3300 respondents who had had premarital sex reported first having sex at the age 16-18 years. In most of the countries round the world, pre-marital sex is a common occurrence.

Well, let us accept the reality of our society today and then weigh pros and cons of premarital sex.
Premarital sex is a delicate issue and a straightforward 'wrong' or 'right' answer is difficult considering changing cultural values and over-exposure of sexual images through media.
Issues of sexually transmitted deceases, unwanted pregnancies and feelings of guilt and fear all weigh too precariously at various angles to give any semblance of balance in a decision to have premarital sex.

Culturally, the most important change that has been occurring over the past few years is that age at which young people marry is on the rise. Typically young people these days are marrying after 25 and even among them there are several who marry after 30 plus.
Now for a person of 25 years of age and above to not have had a single sexual encounter in life is very difficult to imagine considering that sexual desires naturally sets in since one attains puberty. And now with social networking on the web and opportunities to meet people at work places and in groups being part of life today, it would be ridiculous to assume young people won't bond as potential couples and feel attracted to each other.
Let us say there is no fear of sexually transmitted deceases and unwanted pregnancies since all the necessary precautions have been taken care of. How does premarital sex affect you emotionally and mentally…is it better to do it or not do it? That is the top most question on the minds of young people today.

While on the one side there is pant up sexual desire born out of mutual attraction and love and hope of fulfilling it, on the other side there is a fear of guilt, depression or a possible loss of respect and interest on the part of your lover.
Think why you doing it? Is it because media tells you it's the 'in' thing? Because you think everybody else is doing it? Or you want to experiment and gain experience? Or because you are unable to reign in your desire and are seeking pleasure out of sex? Or because you think about sex too casually, like having coffee or eating a burger, and are wondering why everybody else is making a big deal out of it?
Where do you stand in all these questions?

If indulged with a full awareness and in a wholesome manner, premarital sex can help you evaluate your own sexuality, it can make you discover your self at a deeper level, and also it can start you on a spiritual quest if you do introspect your action from all possible angles.
But if you do it impulsively, just because of peer pressure, or are influenced by media, or because your partner is forcing you to, there are chances you will suffer guilt, moral dilemmas, low self-esteem later. This may crack you up from inside and bog you down with its weight.

Awareness of the self, open talk on this between partners, love, trust and care beyond doubt are the pre-conditions for smooth sailing and emotionally scar-free premarital sex.
Somebody said, "It is not pre-marital sex if you don't intend to marry the person". If you do decide on having premarital sexual relation, you should intend to have a long term or marital relation with the partner. Otherwise one or multiple casual relations before marriage can deprive you of a singular deeper sexual experience and make you unfocussed with little notion of the self.
Think of sex not as a body experience, but as emotional and spiritual experience too. A complete integration of body, mind and spirit in all actions in life is the way to be.
Only a total awareness of self gives you a license to flow with your inner impulses including that of premarital sex.