When you have regular contractions before your 37 weeks of pregnancy, and if you deliver your baby before due date, then you have pre term labor and birth. They can be both intentional and spontaneous.

Some reasons for the latter are:

1. Genital tract infections, like chlamydia, bacterial vaginosis, and trichomoniasis
2. Placenta problems, such as placenta previa or placental abruption
3. Structural abnormalities of the uterus or cervix
4. Other diseases like sickle cell anemia, diabetes, severe asthma, inflammatory bowel disease, chronic active hepatitis, or lupus and non-uterine infections, like abdominal surgery, kidney infection, a gum infection (periodontitis), and trauma to the abdomen can cause pre term labor and birth.

Risk factors:

1. If you are pregnant with twins or higher number multiples
2. Not in the age group of 17-35yrs
3. Not much, gain in weight during pregnancy or before it.
4. Smoking, alcohol abuse, or drug use during pregnancy
5. Gave birth in the last 18 months
6. High levels of stress (physical and mental)
7. Genetic factors

Symptoms:

1. An increased vaginal discharge, vaginal bleeding or spotting
2. Abdominal pain, cramps, or more than four contractions in one hour
3. Increased pressure in the pelvic area
4. Low back pain

These symptoms are often confusing, as some of them, like the pelvic pressure or low back pain, occur during normal pregnancies too.

Tests to know if you are at risk:

1. Measuring the length of your cervix
2. Fetal fibronectin screening

However, if you get plenty of rest, eat well, see your doctor regularly, take proper hygiene and dental care and manage your stress level, you automatically ensure a healthy full term pregnancy.