First Trimester .. Precautions for Fever.. Please Advise

I don't know the answer to your question, but you should call your OB nurse and talk to her about it, like you are talking about. She should give you advise. If she doesn't, I think I'd find another OB practice...

Regarding neural tube defects, are you taking pregnancy vitamins? One of the best things to prevent neural tube defects, including spina bifida, is folic acid, and it's in pregnancy vitamins. You can go to the pharmacist and talk to him or her about it. The most important time to take them is in the first 8 weeks. It also helps prevents some forms of cleft palate, which developmentally happens at 8 weeks gestation. So, you can see how important it is to get pregnancy vitamins in you ASAP. (Before you conceive is optimal...)

1. call dr for real medical advice.

I had a gi bug when I was preg.. my dr said keep my fever under 102.. and drink plenty of water..

Honestly, I would talk with your OBGYN and get their advice. I think that's the best way to go. I can tell you that I was pregnant and quite sick during my pregnancy and my babies did just fine =) But, as far as how to care for yourself, talk to your doctor.

You are worrying about catching a cold/virus from your son which may or may not happen.
Prevention (from catching it) is your first line of defense.
Hopefully your son is has been vaccinated so you don't have to worry about catching rubella or anything else which is preventable but might be a problem for you to have while you are pregnant.
Wash your hands a lot (at least 20 seconds with soap and water) - especially before you eat or drink anything or before touching your face (eyes/nose/mouth).
Don't take any medications before you are sick - just treat symptoms as they come and talk these things over with your doctor before you do anything.

You probably haven't even been to your OB for your first appt yet. Normally they give you a handout with info on which medications are safe to take in which trimester. I remember having a fever with my third and taking regular strength Tylenol to keep it down.

If you should actually start to develop a fever, you will want to call the OB for instruction.