Signs of Labor

General Feelings

May have flu-like symptoms -- nausea, diarrhea, abdominal cramping. This alone is not a sign of labor and must be accompanied by more positive signs of labor.
Or you may feel "great" and have a "burst of energy"
Or you may feel no different than you have been feeling.

Contractions

Time contractions from the beginning of one contraction to the beginning of the next contraction to determine how far apart they are. Also time from the beginning of one contraction to the end of that contraction to determine how long they last.
True Labor contractions can usually be distinguished from false labor contractions by the following:

Most often felt as radiating from the small of the back to the lower abdomen; or from the front to teh back; or just along the lower abdomen or upper thighs.
Have wavelike pattern -- onset, peak, decent
Should establish a regular pattern that does not change with a change in activity
Should increase in frequency, intensity, and duration
Should be sufficiently hard that breathing patterns are neccessary
Should last at least 30 seconds

Rupture of Membranes

May begin by a slow leak, or
May have a sudden gush of warm liquid
You will not be able to control the flow and the fluid will probably continue to leak until your baby is born, especially with contraction and position change
Notify your doctor if your membranes rupture, even if you are not in labor
The fluid should be clear and odor free
Do not make any vaginal entry after your membranes rupture, such as tub bath or intercourse, It is OK to take a shower

What to do if you think you may be in labor:

RELAX!! Do not begin any breathing until you are no longer comfortable just relaxing with contractions
May eat lightly if you are not nauseated
Don't engage in any strenuous activity or exercise that will make you tired

Notify your doctor and go to the hospital if any of the following occur:

Bloody discharge from the vagina that is of the amount liek you are starting your menstrual period (as distinguished from a pinkish, reddish, or brownish mucous discharge)
You pass any clots
If your membranes rupture and the fluid is green or brown or had a foul odor to it.

PreLabor Symptoms

The physical changes of prelabor can precede real labor by a full month or more - or by only an hour or so (taken from What to Expect When Your Expecting pg 269)

Lightening and Engagement: Usually somewhere between 2 and 4 wks before the onset of labor in first-time mothers, the fetus begins to descend into the pelvis. This milestone is rarely reached in second or later births until labor has actually commenced.
Sensations of Increasing Pressure in the Pelvis and Rectum: Crampiness adn groin pain are particularly common in second and later pregnancies. Persistant low backache may also be present.
Loss of Weight or Cessation of Weight Gain: In general, weight gain slows in teh ninth month; as labor approaches some women lose up to 2 or 3 lbs
A change in Energy Levels: Some ninth-monthers find that they are increasingly fatigued. Others experience energy spurts. An uncontrollable urge to scrub floors and wash woodwork has been related to the "nesting instinct" - in which the female of the species prepares the nest for the impending arrival.
A Change in Vaginal Discharge: You may find that your discharge increases and thickens
Loss of Mucous Plug: As the cervix begins to thin and open, the "cork" of mucus that seals the opening of the uterus becomes dislodged. This gelatinous chunk of mucus can be passed through the vagina a week or 2 before the first real contractions or just as labor begins
Pink or Bloody Show: As the cervix effaces and dilates, capillaries frequently rupture tinting the mucus pink or streaking it with blood. This "show" usually means labor will start in 24 hours - but could be as much as several days away
Intensification of Braxtion Hicks Contractions: These practice contractions may become more frequent and stronger even painful
Diarrhea: Some women experience loose bowl movements just prior to the onset of labor