The risks of teenage pregnancy are vastly overstated to the point that it is virtually a rumor without actual basis.
http://www.mamaye.org/en/evidence/m...pared-women-other-ages-evidence-144-countries
The risk of pregnancy takes a J shaped curve over time in some populations, and rises straight up in others. In the most at risk adolescent populations (though this particular study only evaluated 15+ year olds), there is only a very slight increased risk of complications versus females in their early twenties. They are however at much less risk of complications than females in their thirties. In the least at risk adolescent populations, they are at less risk of complication than females in their twenties.
This paper concludes that the excess mortality risk to adolescent mothers may be less than previously expected, and highlights the very high mortality ratios for women aged 35 and above.
Much of the risk associated with adolescent pregnancy is caused by the hiding of pregnancy until later stages. If we were to reduce the stigma of adolescent sexuality, it stands to reason that pregnancies would be reported earlier and many of these complications would be ameliorated. I'm not in favor of adolescent pregnancy or anything, but it doesn't carry the risks that were once associated with it, and normalizing adolescent sexuality (which inherently exists regardless of acceptance) will do nothing but good things for the health of adolescents and any babies they may perhaps regrettably have.
Additionally, previous research showing that the children of adolescents were at risk of cognitive deficits was proven to be flawed, when all socioeconomic and other factors are controlled for the children of adolescent mothers actually have superior cognition to the children of older mothers, and less risk of developmental disorders such as autism.
http://aje.oxfordjournals.org/content/154/3/212.full
Teenage pregnancies have become a public health issue because of their observed negative effects on perinatal outcomes and long-term morbidity. The association of young maternal age and long-term morbidity is usually confounded, however, by the high prevalence of poverty, low level of education, and single marital status among teenage mothers. The authors assess the independent effect of teenage pregnancy on educational disabilities and educational problems in a total population of children who entered kindergarten in Florida in 1992–1994 and investigate how controlling for potentially confounding factors affects the relation between teenage pregnancies and poor outcome. When no other factors are taken into account, children of teenage mothers have significantly higher odds of placement in certain special education classes and significantly higher occurrence of milder education problems, but when maternal education, marital status, poverty level, and race are controlled, the detrimental effects disappear and even some protective effects are observed. Hence, the increased risk for educational problems and disabilities among children of teenage mothers is attributed not to the effect of young age but to the confounding influences of associated sociodemographic factors. In contrast to teen age, older maternal age has an adverse effect on a child's educational outcome regardless of whether other factors are controlled for or not.
Humans that live past infancy do not live much longer than they ever have, this is a common incorrect understanding. What happened is that infants used to very commonly die, this massively reduced human life expectancy (an average) versus modern times, where infants don't typically die. However, past infancy life expectancy is nearly the same as it always was.
http://www.livescience.com/10569-human-lifespans-constant-2-000-years.html
Discussions about life expectancy often involve how it has improved over time. According to the National Center for Health Statistics, life expectancy for men in 1907 was 45.6 years; by 1957 it rose to 66.4; in 2007 it reached 75.5. Unlike the most recent increase in life expectancy (which was attributable largely to a decline in half of the leading causes of death including heart disease, homicide, and influenza), the increase in life expectancy between 1907 and 2007 was largely due to a decreasing infant mortality rate, which was 9.99 percent in 1907; 2.63 percent in 1957; and 0.68 percent in 2007.
But the inclusion of infant mortality rates in calculating life expectancy creates the mistaken impression that earlier generations died at a young age; Americans were not dying en masse at the age of 46 in 1907. The fact is that the maximum human lifespan — a concept often confused with "life expectancy" — has remained more or less the same for thousands of years. The idea that our ancestors routinely died young (say, at age 40) has no basis in scientific fact.
There are evolutionary advantages to being raped. I know you and most people like to pretend that humans are not animals, but the reality is we are the products of Darwinian evolution. The biologically programmed goal is to disperse your genes as far as possible. If a female is raped and her child inherits genetics that make him more likely to rape from the father, he will in turn spread the mothers genes by raping many females. This mechanism is what led to females affective desire to be raped, as revealed by the fact that it is their third most popular fantasy. Of course cognitively females don't desire to be raped. This is the same thing for males, although many males affectively desire to rape because of the evolutionary advantages associated with it, probably not many of them actually cognitively want to rape (as is the case with me). This is because humans have cognition that allows them to rise beyond their primitive instincts that were evolutionarily formed. Evolution is not a process that cares about morality.
As far as the mental development of adolescents goes, their adult equivalent IQ is in the average range usually by the time they are 13 years old, and it is not usually in the impaired range from the time they are 12 years old. The only systematic way we have to measure cognitive capacity would lead us to believe that adolescents should be as capable of consenting to sex when they are 13 as some non-mentally impaired 18 year olds are, assuming that ability to consent is derived from IQ (I think it largely is, after all someone with an IQ of 20 obviously cannot consent, but someone with an IQ of 120 can. Ability to consent is at least dependent on IQ, though perhaps not exclusively so).
(formula:
http://www.paulcooijmans.com/intelligence/childiq.html)
1 Year Old ---- 6.25 Adult IQ
2 Year Old ---- 12.5 Adult IQ
3 Year Old ---- 18.75 Adult IQ
4 Year Old ---- 25 Adult IQ
5 Year Old ---- 31.25 Adult IQ
6 Year Old ---- 37.5 Adult IQ
7 Year Old ---- 43.75 Adult IQ
8 Year Old ---- 50 Adult IQ
9 Year Old ---- 56.25 Adult IQ
10 Year Old ---- 62.5 Adult IQ
11 Year Old ---- 68.75 Adult IQ
12 Year Old ---- 75 Adult IQ
13 Year Old ---- 81.25 Adult IQ
14 Year Old ---- 87.5 Adult IQ
15 Year Old ---- 93.75 Adult IQ
16 Year Old ---- 100 Adult IQ
Research on the emotional development of adolescents supports that they are capable of making informed choices regarding sexual consent
http://books.google.ch/books?id=YqLr5zfL1UIC&pg=PA69&lpg=PA69&dq=teenage+sex+regret&source=bl&ots=M_nrPxh9PS&sig=xCI9nsFYnFz-yqymoRgZ4ZjsFFg&hl=de&sa=X&ei=FqOYU__vJ6OH4gSNu4GABQ&ved=0CFUQ6AEwBjgU#v=onepage&q=teenage sex regret&f=false
the majority of teenagers who have sex do not regret their decision, and the researchers determined they typically had a healthy and mature understanding of what happened. They also point out that the media attempted to twist the actual science when reporting on it.
Honestly I'm very well versed on these topics and have read a lot of research, you are not likely to surprise me.