A typical pregnancy lasts 37 to 42 weeks, starting from the first day of the last menstrual period, while preterm labor begins before the 37th week. Around 4 out of 5 premature births are due to spontaneous preterm labor, posing risks to the baby’s organ development. Preterm birth is a leading cause of newborn complications and death. Although regular prenatal care helps identify some at-risk women, not all cases are detected. In this post, we want to give you more insight on this topic.
What Are the Risk Factors and Possible Causes?
It is difficult to predict who will develop preterm labor. Certain obstetric conditions and other factors are known to increase a woman’s risk. However, most preterm births occur in women who have no known risk factors. The strongest risk factor for preterm birth is a previous preterm birth, although most women who have had a preterm birth will have a term pregnancy in the future.
Other factors that may increase a woman’s risk include:
- Being pregnant with twins, triplets, or more.
- A history of excisional therapy for the treatment of abnormal Pap smears.
- Conditions of the placenta
- Abnormalities of the uterus.
- Uterine bleeding, especially in the second or third trimester.
- Use of certain “recreational” drugs, such as cocaine.
- Cigarette smoking.
- Some infections.
- Excessive amniotic fluid.
- A short interval between consecutive births.
- Moderate to severe anemia early in the pregnancy.
- Low pre-pregnancy weight and low weight gain during pregnancy.
- Black race.
- Women under 20 years of age.
- Physical or psychological stress
How Can We Detect Preterm Labor?
Two tests have been identified that may be helpful in some settings.
- Cervical length — Ultrasound measurement of the cervix can help to predict the risk of preterm birth; the risk increases as cervical length decreases.
- Fetal fibronectin — A substance called fetal fibronectin is released when the fetal membranes begin to change before labor. If this substance is not present in vaginal discharge preterm birth is unlikely.
What Are the Signs and Symptoms?
The signs of preterm labor are similar to the signs of labor at the end of pregnancy:
- Change in type or amount of vaginal discharge
- Pelvic or lower abdominal pressure or pain
- Constant dull backache
- Menstrual-like abdominal cramps
- Regular or frequent contractions or uterine tightening that may be painless
- Ruptured membranes (broken water)
Is There Any Efficient Treatment?
Treatment can be given in an attempt to slow or stop preterm labor. The primary goal of treatment is to delay giving birth long enough that steroids, which promote the development of the baby’s lungs, can be given and produce the desired effects. Delaying preterm birth also allows the woman to be transferred, if necessary, to a facility that can provide specialized care to a preterm baby.
Treatment to delay giving birth is typically recommended if pregnancy is less than 34 weeks of gestation because babies born before 34 weeks are at particularly high risk for complications of preterm birth. However, if the mother’s or baby’s health is at risk, labor may be allowed to proceed.
Treatments to stop labor — If the mother and baby are healthy, medications are often used to try to relax the uterine muscle and try to stop contractions. Medications used to stop or slow labor are called “tocolytic” drugs. They include terbutaline, nifedipine, and indomethacin. Some of these drugs are given intravenously or by injection while others can be taken orally.
Treatments to help the baby — Steroids can speed the development of a preterm baby’s lungs and are often administered during preterm labor. Steroids help the lungs mature and may promote the production of a substance that prevents the collapse of the small sacs in the lungs where air is exchanged. Steroids also decrease the baby’s risk of bleeding into the brain and other complications, which affect the bowels and circulatory system. They also reduce the risk of death from complications of preterm birth.
If the mother gives birth early, several treatments can be given to support the preterm baby. Over the past decade, significant advances have been made in the care of preterm newborns. However, not all hospitals are equipped to care for them. For this reason, a woman who is at high risk for preterm birth must be treated in a hospital with a neonatal intensive care unit.
How Can We Prevent It?
One crucial measure for pregnant women in preventing preterm labor is to discontinue harmful habits like smoking and recreational drug use. Additionally, for those with a shortened cervix detected during a second-trimester transvaginal ultrasound, healthcare providers may recommend either a daily vaginal progesterone supplement or the placement of a cerclage, which involves stitching to maintain cervical closure.
Conclusion
Preterm labor stands as a profound challenge in pregnancy, but armed with knowledge and proactive measures, its impact can be mitigated. A woman should contact her healthcare provider immediately if she is concerned that she could be in preterm labor. In particular, she should call if she has more than six contractions in an hour that continue despite lying down, if she has leakage of amniotic fluid, or if she has any vaginal bleeding.
The healthcare provider will perform a pelvic examination and may also perform an ultrasound examination. They may also place a monitor on the uterus that electronically records uterine contractions and the baby’s heart rate.