Preterm Birth Prevention: What the Evidence Says Women Can Do—and What Requires Medical Care
Pregnancy often comes with a long list of advice about what women should eat, how they should exercise, how much they should rest, and what they should avoid. When someone has previously experienced preterm labor or birth, that advice can feel even more urgent—and far more overwhelming.
This article was inspired by Every Woman Is Worthy Founder Maggie Winzeler's experience with a late-preterm birth, followed by a second pregnancy that reached 40 weeks. Her original reflections explored what she changed between those pregnancies and what she learned while researching preterm birth.
Years later, the science has evolved. Some ideas that once appeared promising have become better supported; others have been challenged or replaced by new clinical guidance. Maggie's experience with pregnancy and motherhood also had a profound effect on her desire to advocate for women's health, women's rights, informed decision-making, and compassionate care.
This updated guide therefore takes a different approach. It is not a prescription based on one woman's experience. It is a public educational resource examining what current research says, what remains uncertain, and which questions women may wish to discuss with their healthcare providers.
Important: This article is for general education and is not medical advice. Preterm labor requires prompt medical evaluation. Anyone experiencing possible symptoms should contact their maternity-care provider or seek urgent care immediately.
What is preterm birth?
A birth is considered preterm when a baby is born before 37 completed weeks of pregnancy. The World Health Organization further categorizes preterm birth as:
- Extremely preterm: before 28 weeks
- Very preterm: 28 to under 32 weeks
- Moderate to late preterm: 32 to under 37 weeks
Preterm birth may occur after spontaneous labor, after the membranes rupture early, or because a pregnancy complication makes an earlier medically indicated delivery safer for the woman, the baby, or both. (World Health Organization)
Globally, an estimated 13.4 million babies were born preterm in 2020. Complications of prematurity remain one of the leading causes of death among children younger than five, although survival and long-term outcomes vary enormously depending on gestational age and access to high-quality medical care. (World Health Organization)
In the United States, the preterm birth rate was approximately 10.4% in 2024—roughly one in ten births. (CDC)
Preterm labor is not always preterm birth
Preterm labor means labor begins before 37 weeks, including contractions that produce cervical changes. It does not necessarily mean that a baby will be born early. ACOG reports that preterm labor stops on its own in approximately three out of ten cases, although symptoms always warrant medical attention because it is difficult to predict whose labor will progress. (ACOG)
That uncertainty is one reason women should not feel embarrassed about calling their provider or going to the hospital when something feels wrong. A false alarm is preferable to delaying care.
Signs of possible preterm labor
Before 37 weeks, contact your obstetric provider promptly if you experience:
- Regular or frequent contractions or uterine tightening, even if painless
- New pelvic or lower abdominal pressure
- Persistent low, dull back pain
- Menstrual-like abdominal cramps, with or without diarrhea
- A noticeable increase or change in vaginal discharge
- Watery, mucus-like or bloody discharge
- A gush or ongoing trickle of fluid that may indicate your water has broken
ACOG advises women not to wait when these symptoms occur. Call your obstetric provider or go to the hospital for evaluation. (ACOG)
Why does preterm birth happen?
Preterm birth is not a single condition with one cause. It can involve inflammation, infection, cervical changes, placental problems, uterine overdistension, vascular complications, genetic influences, chronic health conditions, environmental exposures, or several factors acting together.
Sometimes no identifiable cause is found. That matters because women frequently blame themselves after an adverse pregnancy outcome, even when nothing they did caused it and nothing they could reasonably have done would have prevented it.
A woman can follow every recommendation and still experience preterm birth. Another may have several known risk factors and deliver at term.
Risk is not destiny, and an outcome is not evidence of personal failure.
Who is at increased risk?
Among the most established risk factors are:
- A previous spontaneous preterm birth
- A short cervix identified during pregnancy
- Early cervical dilation
- Previous cervical procedures or certain cervical injuries
- Multiple pregnancy, such as twins or triplets
- Vaginal bleeding during pregnancy
- Some maternal infections
- Certain uterine or placental complications
- Smoking
- Low prepregnancy weight or significant nutritional deficiencies
- Some chronic conditions, including hypertension and diabetes
- Very short intervals between pregnancies
Many women who give birth early, however, have no known risk factors. (ACOG)
A prior preterm birth is particularly important. ACOG reports that women with a previous preterm birth are approximately two to three times more likely to deliver preterm in a later pregnancy, although recurrence is not inevitable. (ACOG)
Preterm birth is also a women's-equity issue
Preterm birth cannot be understood only through individual lifestyle choices. Access to prenatal care, insurance coverage, transportation, safe housing, nutritious food, paid leave, workplace conditions, environmental exposures and respectful medical treatment can all affect maternal health.
In the United States, substantial racial disparities persist. In 2022, the preterm birth rate among Black women was 14.6%, compared with 9.4% among White women and 10.1% among Hispanic women. (CDC)
Race itself is not a biological explanation. Research increasingly examines the health effects of structural racism, residential segregation, unequal care, chronic exposure to discrimination and the cumulative physiological burden created by these conditions. Studies have associated racial discrimination and highly segregated environments with adverse birth outcomes, including preterm birth. (PubMed)
An international individual-participant meta-analysis involving more than 2.1 million pregnancies also found that babies born to Black women faced higher risks of preterm birth, stillbirth and neonatal death than babies born to White women, even after adjustment for measured maternal characteristics. (PubMed)
The appropriate response is not to imply that Black women need to make better choices. It is to improve access, continuity, safety, accountability and respect throughout maternal healthcare.
Every woman deserves prenatal care that listens to her, recognizes her symptoms, takes her pain seriously and responds before a preventable crisis occurs.
What can women do to support a healthy pregnancy?
No food, supplement, exercise program or mindset can guarantee a term birth. Still, several practices support maternal health and may lower risk in some populations.
The strength of the evidence varies. Some recommendations are well established. Others are associated with better outcomes but have not been proven to directly prevent preterm birth.
1. Begin prenatal care early and continue it consistently
Prenatal appointments allow clinicians to review pregnancy history, identify chronic conditions, monitor blood pressure and fetal growth, evaluate symptoms, screen for infections, assess medication safety, and determine whether additional surveillance is appropriate.
WHO recommends beginning antenatal care during the first trimester and having repeated contacts throughout pregnancy so potential complications can be identified and managed. (World Health Organization)
For someone with a previous spontaneous preterm birth, early care is especially important because a plan may include serial cervical-length measurements or referral to a maternal-fetal medicine specialist.
Questions to ask:
- Does my history place me at elevated risk?
- Would consultation with maternal-fetal medicine be appropriate?
- Should my cervical length be monitored?
- What symptoms should prompt an immediate call or hospital visit?
- Which preventive treatments apply to my specific history?
2. Do not smoke, and seek support if quitting is difficult
Smoking during pregnancy is an established modifiable risk factor for preterm birth and other adverse outcomes. Avoiding cigarettes, vaping products, recreational drugs and secondhand smoke where possible supports both maternal and fetal health. CDC specifically identifies smoking cessation, avoiding alcohol and drugs, and receiving continuous prenatal care as steps that may reduce risk. (CDC)
This should not be framed as a moral judgment. Nicotine dependence is a health condition, and pregnant women deserve practical, non-punitive help rather than shame.
A healthcare professional can recommend pregnancy-appropriate cessation support.
3. Follow a nutrient-dense eating pattern rather than chasing a "perfect" pregnancy diet
Adequate nutrition supports placental function, maternal blood volume, fetal development and the management of conditions such as anemia and gestational diabetes.
Evidence increasingly supports dietary patterns resembling the Mediterranean diet: vegetables, fruit, legumes, whole grains, nuts, seeds, olive oil, fish and other nutrient-dense protein sources, with fewer highly processed foods.
A 2024 systematic review and meta-analysis found that greater adherence to a Mediterranean dietary pattern during pregnancy was associated with better several perinatal outcomes, including a lower risk of preterm birth. The authors emphasized that the evidence included a mixture of observational studies and clinical trials and that additional research across diverse populations is still needed. (PubMed)
A larger 2026 review incorporating more than 180,000 pregnancies similarly found associations between Mediterranean-diet adherence and lower risks of gestational diabetes, preterm delivery, low neonatal weight and abnormal fetal growth. (PubMed)
Practical approach — a supportive pregnancy eating pattern may include:
- Vegetables and fruit in a variety of colors
- Beans, lentils and other legumes
- Whole grains
- Eggs, poultry, fish, dairy or appropriately planned plant-based alternatives
- Nuts, seeds and olive oil
- Adequate iron, folate, calcium, iodine, choline and protein
- A prenatal vitamin recommended by a qualified clinician
Women dealing with severe nausea, food insecurity, eating disorders, gastrointestinal disease or complex medical conditions may need individualized support. Advice that assumes everyone can easily afford or tolerate an idealized diet ignores real barriers.
4. Discuss omega-3 intake with a qualified clinician
Omega-3 long-chain fatty acids—particularly DHA and EPA—play roles in fetal neurological and visual development. Research also suggests that increasing omega-3 intake during pregnancy may reduce some early-preterm and preterm births.
A scientific consensus statement based on randomized trials and systematic reviews concluded that omega-3 long-chain fatty acid intake can prevent a proportion of preterm births, although the effect may differ according to baseline dietary intake, supplement dose and individual population. (PubMed)
A 2024 European obstetric position statement likewise described an association between omega-3 intake and reduced early and overall preterm birth risk. (PubMed)
That does not mean every pregnant woman should independently begin a high-dose fish-oil supplement. Supplement quality, dosage, diet, medications, bleeding risk and individual medical history matter.
Women can ask their provider whether they are obtaining enough DHA and EPA through pregnancy-safe, low-mercury fish or whether a prenatal omega-3 supplement is appropriate.
Ground flaxseed, chia seeds and walnuts contain alpha-linolenic acid, another omega-3 fatty acid, but the body converts only a limited amount into DHA and EPA. They remain nutritious foods, but they are not nutritionally identical to marine sources of DHA and EPA.
5. Stay hydrated—but do not treat water as a proven prevention therapy
Dehydration can contribute to dizziness, headaches and, in some women, uterine irritability or temporary tightening. Fluid needs also rise during pregnancy.
However, evidence does not establish that drinking an unusually high volume of water prevents spontaneous preterm birth. Hydration should therefore be framed as part of healthy pregnancy care, not as a treatment or guarantee.
Women should drink regularly, increase fluids during heat, exercise, vomiting or diarrhea, and contact their provider when they cannot keep liquids down or notice signs of dehydration.
A clinician may provide individualized guidance when a woman has kidney disease, heart disease, severe swelling, hyperemesis or another condition affecting fluid balance.
6. Exercise is generally safe in uncomplicated pregnancies
The original version of this article questioned whether high-intensity interval training might lower progesterone and contribute to preterm labor. Current evidence does not support making that broad claim.
ACOG states that physical activity during an uncomplicated pregnancy is generally safe and desirable. Women without contraindications should usually be encouraged to continue or begin aerobic and strength-conditioning activity, with modifications as pregnancy progresses. (ACOG)
Randomized-trial evidence has not shown that ordinary aerobic exercise increases preterm birth among women with uncomplicated singleton pregnancies. One meta-analysis found nearly identical preterm birth rates among exercising and non-exercising groups. (PubMed)
Broader research suggests leisure-time physical activity may be associated with an equal or lower preterm-birth risk, although the results differ by population and study design. (PubMed)
What about vigorous exercise or HIIT?
Some experienced exercisers may safely continue vigorous activity during an uncomplicated pregnancy, but "safe" depends on the woman, pregnancy, symptoms, training history and type of exercise.
A pregnant athlete's program may need changes related to:
- Balance and fall risk
- Heat exposure
- Hydration
- Pelvic-floor symptoms
- Abdominal trauma risk
- Joint instability
- Dizziness or breathlessness
- Placental or cervical complications
- Fetal growth or other clinical findings
Women with prior preterm birth, cervical shortening, bleeding, ruptured membranes, significant heart or lung disease, severe anemia, preeclampsia or other complications should receive individualized guidance.
The most accurate message is not "HIIT causes preterm labor." It is: Exercise is beneficial for most pregnant women, but intensity and activity selection should be adapted to medical history, pregnancy complications, symptoms and clinician recommendations.
7. Routine bed rest is not recommended
Resting when tired is reasonable. Prescribed bed rest or broad activity restriction is different.
ACOG advises that activity restriction should not routinely be used to prevent preterm birth because research has not shown that it improves outcomes. Prolonged bed rest can increase the risk of blood clots, bone loss, muscle deconditioning and psychosocial strain. (ACOG)
ACOG's patient guidance similarly states that bed rest is not recommended for women at risk of preterm birth. (ACOG)
This does not mean women should ignore pain, contractions, bleeding or exhaustion. It means restrictions should be based on a specific clinical reason rather than the assumption that lying down prevents early delivery.
8. Consider pregnancy spacing—but understand the nuance
Research has repeatedly associated very short intervals between a live birth and the next conception with increased risks of preterm birth and other adverse outcomes.
A 2023 systematic review involving nearly 47 million pregnancies found a J-shaped relationship: intervals shorter than six months and intervals of five years or longer were associated with higher risks than intervals of approximately 18 to 23 months. (PubMed)
A 2025 analysis of more than 8.6 million pregnancies found the lowest preterm-birth risk in its dataset among intervals of 24 to 29 months compared with intervals under five months. (PubMed)
But these are population-level associations, not rigid rules for every family. Age, fertility, contraception access, previous pregnancy complications, miscarriage history and personal circumstances all matter.
Importantly, evidence regarding timing after miscarriage differs from evidence following a live birth. One systematic review found that conception within six months after miscarriage was not associated with worse outcomes and was linked to a lower observed risk of subsequent preterm delivery in the included studies. (PubMed)
Women deserve individualized family-planning conversations—not blanket instructions detached from their lives.
9. Take oral health seriously, while keeping the evidence in perspective
Pregnancy can make gums more prone to inflammation and bleeding. Periodontal disease has also been associated with adverse pregnancy outcomes, possibly through inflammatory and infectious pathways.
Dental care during pregnancy is important and generally safe. Women should continue brushing, flossing and routine dental treatment and seek care for pain, swelling, infection or persistent gum bleeding.
Whether treating periodontal disease directly prevents preterm birth is less certain. Earlier reviews found no clear reduction, in part because studies varied in quality and design. (PubMed)
A more recent meta-analysis of 14 randomized trials suggested that periodontal treatment may produce a modest reduction in preterm birth, but its confidence interval included the possibility of little or no benefit. (PubMed)
The balanced conclusion is: Oral healthcare supports a woman's overall health during pregnancy and may offer obstetric benefits, but flossing or periodontal treatment should not be presented as a guaranteed method of preventing preterm birth.
10. Identify and treat infections appropriately
Some urinary, reproductive and systemic infections are associated with preterm labor or medically indicated early delivery. Prenatal care may include screening for asymptomatic bacteriuria, sexually transmitted infections and other conditions depending on history and clinical guidelines.
Women should contact a provider for symptoms such as:
- Pain or burning with urination
- Fever
- Flank pain
- Foul-smelling or unusual discharge
- Genital sores
- Persistent pelvic pain
- Fluid leakage
- Feeling acutely unwell
Antibiotics should not be taken "just in case," and probiotics should not be presented as a proven substitute for diagnosis and treatment.
11. Support mental health without implying that anxiety causes preterm birth
Chronic stress, trauma, depression and anxiety deserve care during pregnancy. Some observational research has linked high prenatal stress with adverse outcomes, although results for preterm birth are not entirely consistent and cannot prove that stress alone caused the outcome. (PubMed)
Women should never be told that they delivered early because they "worried too much" or failed to stay positive. That framing is both scientifically simplistic and emotionally harmful.
Mental-health support matters because the woman matters.
Helpful forms of support may include:
- Psychotherapy
- Pregnancy-safe medication when indicated
- Social and peer support
- Trauma-informed maternity care
- Assistance with intimate-partner violence
- Workplace accommodations
- Sleep support
- Practical help with food, transportation or childcare
- Mindfulness, breathing or relaxation practices when personally helpful
Visualization or meditation may help someone cope with uncertainty, but they are not evidence-based substitutes for cervical screening, medication, cerclage or urgent evaluation.
Medical approaches to preventing preterm birth
Lifestyle measures cannot replace medical risk assessment. For women at elevated risk, the most meaningful preventive measures may involve cervical surveillance, progesterone in selected cases, cerclage or specialist management.
Cervical-length screening
A short cervix during the middle of pregnancy is one of the strongest clinical predictors of spontaneous preterm birth.
Cervical length used to guide treatment should be measured by transvaginal ultrasound using standardized technique. SMFM defines a short cervix in a singleton pregnancy without a previous spontaneous preterm birth as a midtrimester cervical length of 25 millimeters or less. (SMFM)
Women with a previous spontaneous preterm birth may be offered serial transvaginal cervical-length measurements. (ACOG)
This is different from a routine digital cervical examination near the end of pregnancy. A cervical exam tells a clinician whether the cervix is currently dilated or effaced; it does not reliably predict the exact date labor will begin.
Progesterone: what has changed?
This is one of the most important updates since Maggie's original article.
For years, weekly injections of 17-alpha hydroxyprogesterone caproate, or 17-OHPC, were commonly offered to women with a previous spontaneous preterm birth. The FDA later withdrew approval of Makena and its generic versions after confirmatory evidence failed to establish sufficient effectiveness.
ACOG now states:
- Intramuscular 17-OHPC is not recommended for preventing recurrent spontaneous preterm birth.
- Vaginal progesterone may be considered for a woman with a singleton pregnancy, a previous preterm birth and a shortened cervix.
- In a singleton pregnancy with a prior spontaneous preterm birth but without a shortened cervix, vaginal progesterone should not be offered solely to prevent recurrence because benefit has not been demonstrated. (ACOG)
For a woman without a previous preterm birth but with a singleton pregnancy and a cervical length of 20 millimeters or less before 24 weeks, SMFM recommends vaginal progesterone. Treatment may also be considered at 21 to 25 millimeters through shared decision-making. (SMFM)
This is an example of science correcting itself. Changing recommendations do not mean earlier patients or clinicians acted irresponsibly. They mean treatment should evolve as stronger evidence becomes available.
Cervical cerclage
Cerclage is a procedure in which a clinician places one or more stitches around the cervix to help it remain closed.
It may be considered for certain women with:
- A history strongly suggestive of cervical insufficiency
- A previous spontaneous preterm birth combined with significant cervical shortening
- Painless cervical dilation during the current pregnancy
It is not routinely recommended for every short cervix. SMFM advises against cerclage for women without a previous preterm birth who have a cervical length between 10 and 25 millimeters but no cervical dilation. (SMFM)
The decision depends on the woman's history, gestational age, cervical findings and potential risks and benefits.
What if preterm labor has already begun?
When clinicians believe an early birth may occur, treatment may focus less on preventing labor indefinitely and more on gaining enough time to protect the baby.
Depending on gestational age and clinical circumstances, treatment may include:
- Antenatal corticosteroids to help fetal organs, particularly the lungs, mature
- Magnesium sulfate for fetal neuroprotection when very early delivery appears imminent
- Tocolytic medication to delay delivery briefly
- Antibiotics when membranes have ruptured early or an infection requires treatment
- Transfer to a hospital with an appropriate neonatal intensive care unit
Tocolytics may delay delivery for approximately 48 hours in selected cases, creating time for corticosteroids, magnesium sulfate or hospital transfer. They are not appropriate in every situation, particularly when delivery is safer for the woman or fetus. (ACOG)
Informed consent and cervical examinations
Pregnant women have the right to understand and participate in decisions about pelvic examinations and other procedures.
A clinician should explain:
- Why an examination is being proposed
- What information it may provide
- Whether it will change clinical management
- What discomforts or risks are involved
- What alternatives exist
- Whether the examination can reasonably be delayed or declined
Routine cervical checks late in pregnancy generally cannot predict the exact timing of delivery. Someone can be several centimeters dilated for days or remain minimally dilated shortly before active labor.
At the same time, a pelvic examination may be medically important when evaluating contractions, bleeding, suspected ruptured membranes or possible preterm labor. Consent and respectful communication should still be part of the process.
Advocacy does not require rejecting medical care. It means receiving enough information to make meaningful decisions wherever a choice exists.
Questions women can bring to prenatal appointments
For women concerned about preterm birth, these questions may help guide a conversation:
- Based on my history, what is my estimated risk of preterm birth?
- Was my previous early birth spontaneous, related to ruptured membranes or medically indicated?
- Should I see a maternal-fetal medicine specialist?
- Would serial transvaginal cervical-length screening be useful for me?
- What cervical measurement would change my treatment plan?
- Would vaginal progesterone apply to my situation under current guidance?
- Under what circumstances would cerclage be considered?
- Are any of my medications, health conditions or infections affecting my risk?
- What kind and intensity of exercise are appropriate for me?
- What symptoms require an immediate call rather than waiting for my next visit?
- Which hospital should I go to if symptoms occur after hours?
- What options do I have if I feel my concerns are being dismissed?
Writing questions down before an appointment and bringing a trusted support person can make it easier to remember answers and speak up.
What women should not be blamed for
The internet is filled with claims that early birth can be prevented by drinking more water, avoiding sex, stopping exercise, taking a supplement, eliminating a food, thinking positively or resting enough.
Some recommendations may be appropriate for an individual woman. None offers universal control over a complex biological process.
A woman who delivers early should not be left wondering whether one workout, one stressful day, one cup of coffee, one missed vitamin or one medical decision caused it.
Preterm birth often reflects interacting biological, obstetric and social factors. In many cases, the cause remains unknown.
The goal of education should be to increase access to timely care—not to create another standard women can be blamed for failing to meet.
Every woman deserves evidence, dignity and compassionate care
Pregnancy can be joyful, physically demanding, uncertain and deeply vulnerable. Women are often expected to navigate enormous decisions while receiving conflicting advice from family members, social media, wellness culture and even healthcare professionals.
Accurate information matters. So does the way that information is delivered.
Every woman deserves:
- Evidence-based prenatal care
- Clear explanations of benefits, risks and alternatives
- Respect for informed consent
- Prompt evaluation when she reports concerning symptoms
- Mental-health support without judgment
- Care that accounts for financial, racial and social barriers
- The freedom to ask questions without being labeled difficult
- Compassion regardless of how her pregnancy unfolds
At Every Woman is Worthy, we believe women's health begins with valuing women's voices.
Knowledge cannot eliminate every uncertainty or prevent every complication. But it can help women recognize warning signs, ask stronger questions, understand changing medical guidance and participate more fully in decisions about their bodies and pregnancies.
Motherhood helped deepen Founder Maggie Winzeler's commitment to advocating for women's health, rights and compassionate support. Her experience is one story—not a universal template. The larger lesson is that every woman navigating pregnancy deserves to be heard, respected and cared for as though her life, health and concerns truly matter.
Because they do.