Maternal Risk Factors for Preterm Birth: What Parents Should Know

Maternal risk factors for preterm birth are conditions or characteristics in the mother that increase the likelihood of delivering a baby before 37 completed weeks of pregnancy. Understanding these risk factors helps expectant mothers and healthcare providers identify situations that require closer monitoring, proactive care, and lifestyle adjustments to improve pregnancy outcomes.

What Preterm Birth Means

Preterm birth happens when a baby is born too early, before the pregnancy reaches full term. Babies born preterm may face challenges with breathing, feeding, temperature control, immunity, and development. By recognizing maternal risk factors early, families can work with clinicians to reduce potential complications and support healthier pregnancies.

Major Maternal Risk Factors for Preterm Birth

1. Previous Preterm Birth

One of the strongest predictors of future preterm delivery is a history of preterm birth in a previous pregnancy. Mothers who had a preterm baby before are more likely to experience it again.

2. Multiple Pregnancy

Carrying twins, triplets, or more increases the demands on the uterus and body, making preterm labor more likely due to physical and hormonal stress.

3. Short Time Between Pregnancies

Becoming pregnant again within a short period—often less than 6–18 months—can limit the mother’s physical recovery and reduce nutrient reserves, increasing the risk of preterm birth.

4. Maternal Age Extremes

Very young mothers (typically teens) and older mothers (often over 35) have higher chances of preterm delivery due to biological and health-related factors.

5. High Blood Pressure and Pre-eclampsia

Maternal hypertension and conditions such as pre-eclampsia (high blood pressure with organ effects) can affect blood flow to the placenta and may necessitate early delivery for the safety of both mother and baby.

6. Chronic Health Conditions

Conditions such as diabetes, kidney disease, autoimmune disorders, and thyroid dysfunction can contribute to preterm labor either through metabolic stress or complications that affect the pregnancy.

7. Infections During Pregnancy

Certain infections—especially of the urinary tract, vagina, cervix, or reproductive organs—can trigger inflammatory responses and cause early labor. Untreated bacterial infections may increase the risk of preterm birth.

8. Cervical or Uterine Abnormalities

Structural issues such as a shortened or weak cervix (cervical insufficiency) or abnormalities in the uterus can make it harder for a pregnancy to progress to full term, increasing the risk for preterm labor.

9. Poor Maternal Nutrition

Inadequate nutrition before and during pregnancy (including low weight and nutrient deficiencies) can compromise fetal growth and contribute to early labor.

10. Lifestyle Factors

• Smoking
• Excessive alcohol use
• Recreational drug use
These exposures affect placental function and fetal development, increasing the risk of preterm birth.

11. High Levels of Stress

Chronic stress, lack of emotional support, and psychosocial challenges have been linked to preterm labor, as stress hormones may influence uterine activity.

12. Placental Problems

Conditions such as placenta previa (where the placenta covers the cervix) or placental abruption (where the placenta detaches early) may lead to medically indicated early delivery.

How Maternal Risk Factors Influence Care

Recognizing maternal risk factors for preterm birth allows healthcare providers to tailor prenatal care, including:

• More regular monitoring and check-ups
• Early screening for infections or metabolic imbalances
• Nutritional counseling and supplementation
• Advice on lifestyle adjustments and stress reduction
• Referrals to specialists when needed

Working closely with a clinician helps address modifiable risks and supports women through higher-risk pregnancies.

When to Seek Prompt Medical Advice

If you experience signs of early labor—such as regular contractions, pelvic pressure, back pain, increased vaginal discharge, or fluid leakage—contact your healthcare provider right away. Early intervention can help slow preterm labor or ensure appropriate care when needed.

Conclusion

Maternal risk factors for preterm birth include a mix of medical history elements, health conditions, lifestyle factors, and biological characteristics that increase the chance of early delivery. Knowing these factors helps women and clinicians work together to monitor pregnancies more closely, make preventive health decisions, and provide targeted support to promote healthier pregnancy outcomes. Early identification and care can make a meaningful difference in both maternal and newborn well-being.