Common questions during the first trimester:

Is it safe for me and my baby to continue running?
If you are healthy, and are not a high risk pregnancy, it is safe to continue running.  In fact, there are many benefits to you and your developing baby (see below).  As runners we are usually very in tuned with our bodies.  This skill must be even more honed during this time.  Your instincts will become a very important indicator to you that you are not pushing yourself too hard.  If you ever feel something painful or even just "off", it's better to stop and walk home.  Always check with your doctor if you are unsure of any symptoms you are experiencing.

Is there a limit to the amount I should run?
There is no specific number that is used as a general guideline.  If you have been regularly logging 40 miles a week, your pregnant mileage will vary as compared to someone who has been running 15 miles per week.  The important thing to remember is that this is not the time to increase your fitness, rather it is a time to maintain as much of your fitness as possible.  You may find initially that you are able to continue your normal mileage.  Later, in the first trimester, fatigue and morning sickness may cut some runs short.  The key is listening to your body and doing what you can without excessively pushing yourself.

Is there a limit as far as intensity/pace?
As with distance, the pace you run will vary upon many individual factors.  You will also notice your pace changing during the course of the pregnancy.  Fatigue may slow you now, but next trimester you may feel good enough to find your old pace again.  Late in the pregnancy you will again slow down.  The pace may change but the effort you expend may be the same. 
The most important thing here is to gauge how hard of an effort you are running at.  You should always run at a pace that allows you to carry on a conversation.  You do not want to be huffing and puffing along.  In fact, leave your running watch at home and just go with how you feel.  

Can I start a running program while I am pregnant?
It is generally advised that you can continue doing whatever activity you are normally accustomed too (within some limits).  But, if pregnancy has made you decide to get moving, there are things that you can do to stay healthy.  Rather then attempt to jump straight into a running program from nothing, it is better advised to walk.  After you are able to complete a 30 minute walk with no problems and, as long as your effort level is such that you can maintain a conversation, you could throw in some easy jogging segments.  One example is walking for 10 minutes and then alternating jogging one minute and walking one minute for the next 10 minutes.  Finish up with a final 10 minutes of walking.  Make sure you listen to your body and maintain a comfortable effort.

What can I expect to experience?
Every woman will have different weird things happen.  I wish there was a list of things to expect, but where would the fun be in that?  There are certainly the common experiences such as morning sickness, calf cramps, and fatigue.  One of my biggest challenges throughout my pregnancies was the increase and urgency with urination.  I always had to make sure I was running near a bathroom since I was stopping every 5 minutes.   

Do I need to eat or drink more?
Being hydrated and having enough energy (calories) is more important now than ever.  Get used to carrying a bottle of water with you all the time.  And enjoy a sports drink while you run. 
This is obviously not the time to worry about weight gain.  You will need to eat more.  How much more is up for debate.  There are many factors to consider, like activity level, when determine how many calories to eat.  If you are like me, you will feel hungry more frequently.  I took this as a sign that my body needed more and tried in indulge in something healthy (okay, sometimes it was a cupcake or cookie).  If you want specific nutritional advice most ob/gyn offices have a dietician on staff.

How much weight will I gain this trimester?
Most women only gain a couple pounds their first trimester.  The good news is that studies show that women who continue to exercise throughout their pregnancy gain an average of 8 lbs less.

How do I deal with morning sickness?

I used to sleep with crackers and bananas on my bedside table.  I would try to take a couple bites before getting out of bed.  This seemed to help some on most mornings, but, as you may have figured out by now, morning sickness is not limited to the morning.  I asked a mom runner friend how she dealt with feeling sick before a run.   She said a good combo of protein and carbs seemed to settle her stomach.  Something like a yogurt or toast with cheese.  You’ll have to experiment with what will work for you.  Hopefully it won’t last too long.  If there is a pattern to the time of day you feel queasy, try setting up your run time around that.

What are the benefits of running for the baby and me?

You will run into people who will think you are doing the worst thing ever for yourself and your baby because you decide to stay active.  Luckily, most attitudes are changing as the research continually shows that there are numerous benefits not only to the mom but to her baby. 
The body is so good at adapting to the demands of what are placed upon it.  Pregnancy itself is a great example of this.  And, as a runner, you have experienced the adaptations that occur with increased fitness.