In the United States, an estimated 12 percent of all pregnancies end in preterm birth – a baby born before 37 weeks pregnant. This rate continues to climb, due to more twin and multiple pregnancies in recent decades. (Being pregnant with multiples puts you at risk for preterm birth.)
Because Braxton-Hicks contractions are common in the second trimester, and since they are sometimes difficult to distinguish from real contractions, you will want to learn about the signs of preterm labor and watch out for them. Signs of preterm labor include a low, dull backache; pelvic pressure (or the feeling that your baby is pushing down); menstrual-like cramps; vaginal bleeding or leaking fluid; contractions that happen every ten minutes (or more); abdominal cramps; and diarrhea.
Some women are more prone to preterm labor and delivery than others. You may be at risk for giving birth too soon if you have a past history of giving birth early; you're pregnant with twins or multiples; you became pregnant due to in vitro fertilization (IVF) or other assisted reproductive technologies; you have cervical or uterine abnormalities; you receive late or no prenatal care during pregnancy; you smoke, drink, or abuse illegal drugs when you're pregnant; you work long hours and you're forced to stand for an extended period of time; you are involved in abusive relationship.
You are also at elevated risk of preterm birth if you experience pregnancy complications, such as high blood pressure or preeclampsia. In addition, women with existing illnesses – including sexual transmitted diseases, diabetes, and clotting disorders – are more likely to go into labor early. Urinary tract infections and vaginal infections can also increase your risk.
While your baby's survival rate at 24 weeks pregnant is roughly 40 percent, he or she will face long-term health problems if born that early. Premature babies face the risk of brain, breathing, and respiratory problems after birth. In addition, they face heighted risk of death within the first week of life. Long-term problems include delayed development and learning problems in school.
Testing for Preterm Labor: Fetal Fibronectin (fFN) test
Because of the risks that go along with preterm birth, you want to avoid this complication if possible. In the second trimester, if you are experiencing any symptoms of preterm labor (or if you're at risk for delivering too soon), your medical team may recommend a fetal fibronectin (fFN) test.
During a fetal fibronectin test, your vaginal and cervical fluids will be checked for the presence of the fetal fibronectin protein – the "glue-like" protein that helps bind the uterine lining and amniotic sac together. In a normal pregnancy, fetal fibronectin doesn't break down and leak out of your uterus until around 35 weeks pregnant, as labor and delivery approaches.
In the second trimester, this protein should not be present in any vaginal fluids. If you receive a negative result, you have a 99 percent chance that you will not go into labor in the next two weeks. However, if the fFN test detects traces of this protein and you get a positive result, it means that your body is getting ready for delivery.
If you get a positive result from the fFN test at this stage in pregnancy, your healthcare provider will create a plan of action to help your baby remain in the womb for longer (if this is possible).
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