Can anyone who knows about or lives in Japan help me with some teen pregnancy questions?

[Nanasi Gombei]

I am a Japanese.

Sex education:
It is not true that there is no sex education in Japan. Please read the report from the government shown below. However many doctors and health-care experts condemn the government that the sex education is really insufficient.
A survey by the National PTA association shows 30% of male high-school senior students and 39% of female high-school senior students had already experienced sexual intercourse in 2005. However the authority hesitates to deliver information about "safe sex" and birth control since it fears that such info encourages teens to have intercourse. The authority strongly wants to keep teen from intercourse, which seems unrealistic.

Pregnancy and abortion:
Men 18 years old and older and women 16 years old and older are legally eligible to marry. Some teenage pregnancy end up with "shot-gun marriage" and the children might be deemed as legitimate child under the provisions of Japanese Civil Code.
(It is true that extramarital children suffer from discriminative treatment in inheritance but they still have family records and can receive public services. National health insurance system covers all Japanese nationals, regardless the child is legitimate or extramarital.)
On the other hand, it is easy to take abortion in Japan and while the total abortion rate is decreasing, abortion by teens are increasing.
In general adults had renounced teen pregnancy but recently teen pregnancy is not a big taboo in Japanese media any more. However, as far as I know through the media, those young fathers and mothers who bear children in their teens generally can not continue their schoolwork, have to engage in low-wage works and live in poverty. I guess families of those couples accepts such pregnancy.

Media:
In Japan, the internet is not censored and anyone including minors can access to pornographic movies and still images.
Magazines containing nude and pornographic photos are sold anywhere including convenience stores. Some manga have sexual contents, too. Many prefectures ban to sell sexual explicit magazines and manga to those under 18 years old, but it is doubtful that those provisions are really effective.
AKB48 and its sister groups whose members dress like high-school girls, sing and dance are really popular in Japan and known to sing implicitly seductive songs sometimes.