Irritable Uterus & Labor Timeline: Understanding Your Pregnancy

Question
I am 19 years old and I am 39 weeks pregnant with my 1st baby. My last menstrual period was on/around Nov. 13, 2004.  I went into the hospital with contractions but it just turned out to be a "false alarm". I was told by the nurse that I had not dilated yet but I had an irritable uterus.  What exactly does that mean? And I was also wondering how fast can I start dilating? Is it something that can happen from one hour to the next?

Answer
For your first baby, you usually will not go into labor until you reach 40 weeks or even up to two weeks later. YOu will start with irregular contractons (Braxton-Hicks) which do nothing to dilate the cervix. Eventually, you will start to get contractions at the level of your belly button that occur every 3 minutes (from the start of one contrction to the start of the next contraction) and each contraction shoulld last (remain hard) for a full minute. When this continues for a full hour, go to be checked. If your cervix has opened up greater than 3-4 cm, you will be admitted to the hospital. Until then, the pain is due to an "irritable uterus". You feel some pain but it does not dilate the cervix. The cervix will not dilate until you have contractions every 3 mintues. Good lUck.