We are still trying to understand why preterm labor happens, causing babies to be born before their time. However, currently we only know what has caused the preterm labor in about half of all of the labors being effected.
When preterm labor starts on its own (as opposed to being induced):
- Infection. About 40-50% of all preterm labor can be traced to infection. Many women do not show classic signs of infection, like fevers. One good note here is that with antibiotic treatment for Group B Strep, we have seen a reduction. Other than for Group B Strep, antibiotics usually lead only to antibiotic resistance and not a reduction in preterm labor rates.
- Bleeding. This does include placental abruption, where the placenta tears away from the uterine wall too early. It also includes bleeding disorders that may be genetic or acquired. Bleeding of any sort should be reported to your doctor or midwife.
- Stretching of the uterus. The stretching or over distension of the uterus has also been linked to preterm labor and birth. This can be caused by fibroids, multiple pregnancies (twins, triplets, etc.), or even having too much amniotic fluid (polyhydramnios).
Research is ongoing as to the causes of preterm labor and how to prevent this dangerous complication. The biggest thing to be aware of are the signs of preterm labor and what risk you are at with your current pregnancy.