Pregnancy and Partner Infidelity: Potential Risks to the Baby

Question
my friend is pregnant and she read an article saying that if her boyfriend/husband is cheating on her that could harm the baby.  I asked her well what about you, meaning if she slept with another man say if her boyfriend/husband seperated would that harm the baby also.  Now, i am not to sure if what she said was correct or not but i would like to know the truth behind both of those.  I care deeply for this friend and want what is best for her and her baby.  If you could get back to me on these questions of mine that would be greatly appreciated.  Thank you for your time and effort.

Sincerely
Dave

Answer
The actually act of sex will not harm the baby.  Either parent having sex is fine.  They should of course be having it with eachother though.
NOW, the twist is STDS.  If the mother aquires a STD then the baby certainly would be at risk.  
They should be having safer sex with condoms exspecially if they are sleeping with more people than eachother.