Labor beginning between 20 and 37 weeks is a "preterm labor/ premature labor".
Cause for preterm labor can be the mother or the baby or both. However, a few common causes of preterm labor include:
• The placenta separating early from the uterus; also called placenta abruptio.
• Twins or triplet pregnancy.
• An infection in the mother's uterus that leads to the start of labor.
• Drug or alcohol use during pregnancy (quantity allowed is still under discussion).
• Amniotic fluid/water loss before the start of labor.
Every pregnant woman should know the symptoms of labor. Here are the common signs of preterm labor.
• Contractions more than four or five per hour.
• Regular contractions that increase in frequency.
• Rhythmic or persistent pelvic pressure.
• Cramps, similar to that during menstruation.
• Severe backache.
• Diarrhea
• A change in vaginal discharge.
• Vaginal bleeding.
• Uneasy or urgent sense that something is wrong.

Things you should know if you have a preterm delivery:
• A pre term baby will be prone to developing infections.
• Their skin will be very thin and underdeveloped, with very less fat under the skin, so they quickly lose heat and are difficult to keep warm.
• They are at-risk of developing respiratory distress syndrome.
• The stomach will still be under developed to accept milk immediately.
• Expect a delay in suckling reflexes.
• Like a full term baby, they might develop infantile jaundice. However, severe or long standing jaundice can be fatal.

Be aware of the risks and signs of preterm labor. But, let fear not take away the joy of pregnancy! Happy motherhood...