While there are drawbacks in women having children while young (let's say, 16-22 years old), at least not demonizing (late) teen pregnancies so they can develop a career as you describe is something that should help include fertility rates.
Think of a 16-17 years old girl who got pregnant by being reckless when having sex. If she's in doubt if she wants to keep the baby (which is likely the way she'll feel), a nudge from a doctor who believes he's doing the right thing by suggesting her to abort may be all it takes for the girl to abort. Want to do increase fertility rates? Try to make sure doctors don't do that and provide advertisement and resources for pregnant women who are considering abortion so they don't abort.
Of course, the next problem if you want to boost fertility rates is that, if that girl keeps her child, she still needs to have one or two extra kids for fertility rates to increase.