Does being emotionally stressed while pregnant affect the fetus?

Let’s say a pregnant women is being severely emotionally stressed by internal or external things happening in her life (beyond just being pregnant). Is there any way that severe emotional stress will physically impact fetal development if all other factors like nutrition and physical exertion are being handled adequately?

There are tons of old wives’ tales that say yes. Of course tons of old wives’ tales are nonsense, too.

I wish I could remember where I read the theory that extreme stress could affect a pregnant woman’s hormones and thereby possibly affect the sexual orientation of the fetus. (This also may be complete b.s., of course.)

In any case, these days women are cautioned not to ingest even a single aspirin or glass of wine. It’s also been pretty widely said that prolonged stress affects one’s immune system, raises one’s blood pressure, and has other deleterious influences. It seems logical to me, therefore, that prolonged stress could well have a tendency to have some impact on a fetus, but that like everything else will vary from one person to the next.

IANAD, and one reason I replied is that I’m interested in any actual facts that may be brought up in future responses.

Here is a relatively recent (2003) article that discusses this:

The conclusion of this study was that stress can cause preterm birth, low birthweight, and other poor health outcomes. But other studies have not found such an association.

One of the reasons sometimes noted for the discrepancy between these types of findings is that the type of stress matters; for example “good” stress – the type where you have a problem that you can/do overcome – is ok, versus “bad” stress – the type that is beyond your control is detrimental.

Homosexuality, dyslexia, poor immunity, ADD, mental retardation, and (gasp!) left handedness, just to name a few.

But hey, don’t stress out about it, it’ll just make it worse…