Premarital sex: I don't think this is a big deal. No one should need a piece of paper or a ring to confirm that a couple can have sex together.
Teenage pregnancy: Teenagers who say they want to get pregnant are ignorant fools. They are not mature or experienced enough to raise a child. They still have a life to live, and so much to discover before sacrificing all they love and want to have a kid.
Abortion: Only if the parent is not ready or too young to have a baby or is sickly. If a woman wants to have an abortion because of the gender of the child, thats not a good enough reason.
Premarital Sex - My opinion is whether you have sex before marriage or not is a personal (or religious) choice and its something only you can choose to do or not to do. I definitely believe that monogamy is the way to go and saving yourself for someone special would be the ideal thing to do but not that you should necessarily have to wait for wed lock unless of course, its what you choose to do.
Teen Pregnancy - This is another personal choice.. I am 17 years old and expecting my first child in June and it wasn't an accident. My partner and I planned to have children and now I am pregnant and we are both over the moon to be expecting a baby, I have always been very maternal and have wanted a baby since I was only a child myself but I am happy I waited until now. I don't regret becoming pregnant young and believe this is another personal choice, but you should really be planned out properly before jumping into things as you want what is best for your child. Its best to be financially stable and in a stable long term relationship which is rare in teenagers. Me and my partner had talked everything through first and are happy with the way things are working out.
Abortion - I DO NOT believe in abortion!! I think its disgusting.. It might even be seen to some people as murder ( I agree ) and there are other options which should be carried out rather then abortion. Abortion should not even be legal! (Unless under extreme circumstances including a women becoming pregnant from rape and she is in a very bad way, and could not carry the child full term to give it up for adoption or something like that).
Premarital sex- I think if the couple are responsible and practice safe sex to avoid STD's and pregnancy (unless they don't care to be married before they have a baby) then it's not a big deal.
Teenage pregnancy- Considering my mother had me at 17 years old and is a successful attorney with a family who loves her I have an unbiased opinion. She was married at 16 so maybe it's not viewed the same, who knows.
Abortion- my opinion can be summed up with a Dr. Seuss quote "A persons a person no matter how small" from Horton Hears a Who.