10 Common Causes for Preterm Births

While this list does provide many of the common causes for premature births, it is important to remember that everyone is different and and every pregnancy is different.  Remember that only your doctor can evaluate your own individual situation and determine the correct prognosis for your pregnancy and your baby.

1. Previous Premature Deliveries - One of the most important risks for a premature birth is if you have already had a premature baby.  The probability is that you have between a 20% and 40% chance of having another premature delivery.
2. Previous Second Trimester Abortion - Women who have had an abortion in their 2nd trimester have a higher risk for preterm births because the surgical procedure requires a wide dilation of the cervix, which can damage the cervix and lead to cervical incompetence.  Having one 1st trimester abortion doesn't increase your risk; however, having several 1st trimester abortions may increase your risk.
3. Pregnancies within 6 months of each other - Becoming pregnant less than six months after a previous delivery may cause a premature birth because your body may not have had enough time to fully recover.
4. Malformations of the Uterus - Having problems with your uterus, such as fibroids or a uterus with an abnormal shape.
5. Cervical incompetence  - A woman's cervix can open too early in the pregnancy, which may cause a premature delivery.  There is a simple surgical procedure called a cerclage, which can be done during your pregnancy.  This can help keep the cervix closed until the baby is full term.
6. Multiple Gestation - Twins have a 25% to 50% chance of being born before term, and that rate rises with each additional fetus.
7. Smoking - Cigarette Smoking reduces blood flow to the placenta and oxygen to the fetus, which causes poor fetal growth, preterm rupture of membranes and premature births.
8. Low maternal weight  - Women who weigh less than 100 pounds at the beginning of their pregnancy or who do not gain enough weight during their pregnancy have an increased risk of having a premature baby.
9. Little or no Prenatal Care - Women who do not receive prenatal care are more likely to deliver prematurely. Prenatal care is important to the health of the mother as well as the baby.
10. High Blood Pressure- This can be an isolated problem; however it can lead to preeclampsia during pregnancy, which often necessitates a premature delivery.