Stillbirth Risk

Stillbirth risk refers to the chance that a baby dies before or during birth after a certain point in pregnancy, usually at 20 weeks of gestation or later in the United States, though definitions can vary by country. It matters because stillbirth is a serious pregnancy outcome with many possible causes, including placental problems, maternal health conditions, fetal abnormalities, infection, and complications during pregnancy or labor. For men and couples trying to conceive, understanding stillbirth risk is also relevant because reproductive health, age, genetics, lifestyle, and shared medical factors can influence overall pregnancy outcomes.

Key takeaways
What is stillbirth risk?
Why it matters
What stillbirth risk means in men's health and fertility
Causes and risk factors
Warning signs and symptoms
What is normal vs higher risk?
Tests and evaluation
Evaluation after a stillbirth
Prevention and risk reduction
Treatment and management
Stillbirth compared with related terms
Questions to ask your doctor
Myths and misconceptions
FAQs
References

Key takeaways

Stillbirth means fetal death later in pregnancy, often defined as 20 weeks or more in the U.S., and risk changes based on maternal, fetal, placental, and pregnancy-related factors.
Most pregnancies do not end in stillbirth, but certain conditions raise risk, including high blood pressure, diabetes, smoking, obesity, fetal growth restriction, placental problems, and advanced maternal age.
Decreased fetal movement can be an important warning sign and should be reported promptly to a clinician. Guidance from the American College of Obstetricians and Gynecologists supports urgent evaluation when movement changes.
Some stillbirths are linked to congenital or genetic conditions, infection, umbilical cord complications, or labor complications, while others remain unexplained even after testing.
Men's health matters too. Paternal age, genetics, environmental exposures, and overall reproductive health may affect pregnancy outcomes, although stillbirth usually reflects multiple interacting factors rather than a single male cause.
Prenatal care, control of chronic disease, avoiding tobacco and substance use, sleep and weight management, and close monitoring of high-risk pregnancies can help reduce risk.
After a stillbirth, recommended evaluation may include placental examination, fetal testing, and review of maternal and family history, as outlined by ACOG guidance on management of stillbirth.
If you notice decreased fetal movement, bleeding, fluid leakage, severe abdominal pain, or symptoms of preeclampsia, seek medical care without delay.

What is stillbirth risk?

Stillbirth risk is the likelihood that a pregnancy ends in stillbirth. A stillbirth is different from a miscarriage because it occurs later in pregnancy. In the United States, stillbirth is generally defined as fetal death at 20 weeks of pregnancy or later, while some international definitions use 24 or 28 weeks depending on reporting standards and public health systems. The CDC stillbirth overview and the World Health Organization both recognize stillbirth as an important global health issue.

When people search for stillbirth risk, they often want to know:

What increases the chance of stillbirth?
Can stillbirth be prevented?
What week of pregnancy carries the highest risk?
Are there warning signs?
What does stillbirth risk mean after fertility treatment, IVF, or a prior pregnancy loss?

The answer is that risk is not one fixed number. It depends on the stage of pregnancy, maternal health, fetal growth, placental function, prenatal care, and other individual factors.

At a glance

Definition: The chance of fetal death later in pregnancy.
Common contributors: Placental insufficiency, maternal chronic disease, fetal abnormalities, infection, and pregnancy complications.
Important warning sign: Reduced or absent fetal movement.
Can risk be lowered? Often yes, through prenatal monitoring and management of modifiable factors.

Why it matters

Stillbirth risk matters because it helps guide prenatal care, testing, timing of delivery, and monitoring during pregnancy. Identifying higher-risk pregnancies can allow clinicians to follow fetal growth more closely, monitor blood pressure and blood sugar, evaluate the placenta, and decide whether additional surveillance or earlier delivery is safer.

It also matters emotionally and practically. Fear after a previous pregnancy loss is common. Couples may want clear information about recurrence risk, what can be investigated, and what can be done differently in a future pregnancy. Evidence-based care can help replace uncertainty with a plan.

Public health data show that stillbirth remains a major issue even in high-resource countries. The National Center for Health Statistics and the CDC both track stillbirth rates and disparities across populations.

What stillbirth risk means in men's health and fertility

Stillbirth is often discussed as a pregnancy complication, but it is also relevant in men's reproductive health. That does not mean fathers directly cause stillbirth in most cases. Instead, male factors can be part of the broader picture of conception, embryo development, placental biology, and inherited risk.

Paternal factors that may matter

Paternal age: Advanced paternal age has been associated in some studies with adverse pregnancy outcomes, though the degree of effect varies and is often smaller than maternal factors.
Genetic abnormalities: Sperm can carry chromosomal or DNA damage that may contribute to embryo or fetal problems in some pregnancies.
Lifestyle exposures: Smoking, heavy alcohol use, anabolic steroids, some occupational toxins, heat exposure, and environmental chemicals may affect sperm quality.
General health: Obesity, poorly controlled diabetes, sleep apnea, and chronic inflammation can impair reproductive health.
Infections and sexually transmitted infections: Some infections can affect fertility or pregnancy health indirectly.

The science here is still evolving. A man with abnormal semen parameters does not automatically face a high stillbirth risk, and most stillbirths cannot be traced to one isolated male factor. But for couples planning pregnancy, optimizing male health before conception is sensible and may improve broader reproductive outcomes. The NICHD stillbirth information and fertility literature both support looking at pregnancy as a couple-level health event, not only a maternal one.

When men should pay special attention

There is a history of recurrent pregnancy loss or stillbirth.
A previous pregnancy had a known genetic or congenital issue.
You have fertility problems, very abnormal semen analysis results, or known DNA fragmentation concerns.
You have substantial occupational or environmental toxin exposure.
You are using testosterone or anabolic steroids, which can suppress sperm production.

Causes and risk factors

Stillbirth can happen for many reasons, and sometimes no clear cause is found even after thorough testing. In general, the main categories include placental problems, fetal conditions, maternal medical issues, umbilical cord issues, infection, and complications during labor or delivery.

Common causes and contributors

Placental problems: Placental insufficiency, placental abruption, and poor placental blood flow are major contributors. The placenta is essential for oxygen and nutrient delivery.
Fetal growth restriction: Babies who are smaller than expected because of impaired growth have a higher risk of stillbirth. ACOG notes the strong link between growth restriction and stillbirth in patient guidance.
Congenital anomalies and genetic conditions: Structural abnormalities or chromosomal issues can increase risk.
Maternal high blood pressure and preeclampsia: These can reduce placental blood flow and threaten both mother and baby.
Diabetes: Poorly controlled preexisting or gestational diabetes can raise risk.
Obesity: Higher body mass index is associated with increased stillbirth risk in multiple studies, including large analyses in The Lancet.
Smoking, alcohol, and substance use: Smoking is a well-established risk factor. The NHS and CDC both emphasize smoking cessation during pregnancy.
Infection: Certain bacterial, viral, or parasitic infections may contribute, depending on timing and severity.
Multiple pregnancy: Twins and higher-order pregnancies can carry greater risk.
Advanced maternal age: Risk tends to rise with age, especially later reproductive years.
Previous stillbirth: A prior stillbirth raises recurrence risk, though many future pregnancies still result in live birth with proper evaluation and care.
Sleep and position factors: Maternal sleep-disordered breathing and some sleep-related factors are being studied, though not every association proves direct causation.

Risk factors table

Risk factor	How it may affect stillbirth risk	Potential next step
High blood pressure or preeclampsia	Can reduce blood flow to the placenta and baby	Close prenatal monitoring, blood pressure control, timely delivery planning
Diabetes	Can affect fetal growth, placental function, and pregnancy complications	Optimize blood sugar before and during pregnancy
Smoking	Associated with placental problems and reduced oxygen delivery	Stop smoking and avoid secondhand smoke
Obesity	Linked with higher rates of hypertension, diabetes, and stillbirth	Preconception counseling and pregnancy risk management
Fetal growth restriction	Signals that the baby may not be getting enough oxygen or nutrients	Serial ultrasounds and fetal surveillance
Placental abruption	Placenta separates from the uterus too early	Urgent medical assessment
Previous stillbirth	Raises recurrence risk, depending on cause	Specialist review before or early in next pregnancy
Advanced maternal age	Risk generally increases with age	Individualized prenatal care and monitoring
Congenital or genetic condition	May affect fetal development or survival	Genetic counseling and targeted testing
Infection	Some infections can harm the fetus or placenta	Prompt evaluation of fever, illness, or suspected exposure

It is important to separate risk factor from cause. A risk factor increases the chance of stillbirth but does not mean stillbirth will happen. Many people with one or more risk factors have healthy pregnancies.

Warning signs and symptoms

Stillbirth itself may not cause obvious symptoms until evaluation shows no fetal heartbeat, but some warning signs can signal a problem that needs urgent attention.

Possible warning signs during pregnancy

Decreased or absent fetal movement
Vaginal bleeding
Fluid leakage
Severe abdominal pain or contractions
Severe headache, vision changes, swelling, or high blood pressure symptoms that could suggest preeclampsia
Fever or signs of infection

Reduced fetal movement is one of the most important symptoms to act on. The NHS advises contacting maternity care services immediately if your baby is moving less than usual or if movements stop.NHS fetal movement guidance

These symptoms do not always mean stillbirth is occurring. They do mean the pregnancy should be checked promptly.

What is normal vs higher risk?

There is no single "normal stillbirth risk" that applies equally to every pregnancy. Risk changes over time and depends on individual clinical factors. In general, a healthy pregnancy with routine prenatal care and no major complications has a lower risk than a pregnancy complicated by hypertension, diabetes, poor fetal growth, placental disease, or prior pregnancy loss.

What tends to suggest lower risk

Regular prenatal care
Normal fetal growth and anatomy scans
No significant maternal medical conditions
Normal blood pressure and glucose screening
No smoking, drug use, or major high-risk exposures
Reassuring fetal movement and testing when performed

What tends to suggest higher risk

Prior stillbirth or recurrent pregnancy loss
High blood pressure, preeclampsia, or diabetes
Fetal growth restriction
Placental insufficiency or placental abruption
Multiple gestation
Congenital anomalies or abnormal genetic testing
Reduced fetal movement
Smoking, substance use, or poor access to prenatal care

Some families search for specific week-by-week stillbirth risk. In most pregnancies, absolute risk remains low, but because pregnancy lasts many weeks, clinicians pay close attention to risk changes near term and post-term. In some high-risk pregnancies, early delivery may reduce danger more than continuing the pregnancy.

Tests and evaluation

Stillbirth risk is not measured by one test alone. Clinicians estimate risk by combining history, symptoms, physical findings, and pregnancy monitoring.

Tests that may help assess risk during pregnancy

Ultrasound: Used to assess fetal growth, anatomy, amniotic fluid, placental appearance, and sometimes Doppler blood flow.
Nonstress test: Monitors fetal heart rate patterns.
Biophysical profile: Combines ultrasound findings with fetal heart rate data.
Blood pressure monitoring: Screens for hypertension and preeclampsia.
Blood glucose testing: Looks for gestational diabetes or control of preexisting diabetes.
Maternal blood tests: May assess infection, anemia, clotting disorders, or other conditions when clinically indicated.
Kick counts or fetal movement tracking: Useful when movement patterns change, though formal methods vary.

Not every pregnancy needs every test. Higher-risk pregnancies usually need more intensive surveillance. The ACOG guidance on antenatal fetal surveillance outlines when monitoring may be appropriate.

What abnormal results may mean

Poor fetal growth: The baby may not be receiving enough placental support.
Low amniotic fluid: Can signal placental dysfunction or other fetal concerns.
Abnormal heart rate testing: May suggest fetal stress.
Abnormal Doppler studies: Can point to impaired blood flow, especially in growth-restricted pregnancies.
Maternal lab abnormalities: Could indicate infection, diabetes, hypertensive disease, or other medical contributors.

Evaluation after a stillbirth

When a stillbirth occurs, careful evaluation may help identify a cause and guide future pregnancy planning. According to ACOG's management of stillbirth consensus, the most useful parts of evaluation often include placental pathology, fetal examination, and targeted maternal testing.

Common parts of the workup

Placental, cord, and membrane examination: Often one of the highest-yield components.
Fetal external exam or autopsy: Can identify structural abnormalities or clues to cause.
Genetic testing: Karyotype or chromosomal microarray may be considered.
Maternal blood tests: May look for fetomaternal hemorrhage, antiphospholipid syndrome, diabetes, infection, or other conditions.
Review of pregnancy course: Includes blood pressure, fetal growth, ultrasound history, and labor events.

Even with thorough investigation, some stillbirths remain unexplained. That can be deeply frustrating, but it is common and does not mean the evaluation failed. It reflects the limits of current medical knowledge.

Prevention and risk reduction

Not every stillbirth can be prevented. Still, many pregnancies benefit from steps that lower avoidable risk and improve early detection of complications.

Ways to reduce stillbirth risk

Get early and consistent prenatal care. This helps identify blood pressure issues, diabetes, fetal growth problems, and placental concerns.
Manage chronic conditions before and during pregnancy. Good control of hypertension, diabetes, thyroid disease, and autoimmune disease matters.
Stop smoking and avoid alcohol and non-prescribed drugs. The CDC and NHS both emphasize smoking cessation in pregnancy.
Monitor fetal movements. Report reduced movement right away.
Attend recommended scans and testing. Growth scans and antenatal monitoring are especially important in high-risk pregnancies.
Discuss delivery timing. In some high-risk pregnancies, waiting longer may be less safe than planned delivery.
Optimize preconception health. This includes weight, blood sugar, nutrition, sleep, and medication review.
Address male fertility and health factors. Men can improve overall reproductive health by stopping smoking, limiting heavy alcohol use, treating sleep apnea, avoiding testosterone if trying to conceive, and managing obesity or metabolic disease.

Preconception checklist for couples

Review medications with a clinician.
Control diabetes and blood pressure before conception when possible.
Take folic acid if recommended for the partner trying to conceive.
Update vaccines as advised.
Review family history for genetic disorders.
Address abnormal semen analysis or fertility issues early.
Reduce toxin exposure at home and work.

Treatment and management

There is no single treatment for stillbirth risk because management depends on the underlying reason risk is elevated. The goal is usually to monitor the pregnancy carefully and intervene before a preventable loss occurs.

Possible management strategies

Closer surveillance: More frequent prenatal visits, ultrasounds, or fetal testing.
Blood pressure control: Medication and preeclampsia monitoring where needed.
Diabetes management: Blood sugar monitoring, diet, medication, or insulin.
Treatment of infection: If a specific infection is identified.
Low-dose aspirin in selected pregnancies: May be recommended for preeclampsia prevention in certain high-risk individuals based on clinical guidance.
Specialist referral: Maternal-fetal medicine, genetics, or other specialty care.
Planned delivery: Induction or cesarean may be recommended if continuing the pregnancy becomes riskier than delivery.

After a previous stillbirth, care in the next pregnancy often includes a more individualized plan. This may involve early dating ultrasound, targeted anatomy scanning, fetal growth surveillance, and discussion of delivery timing.

Stillbirth compared with related terms

Term	Meaning	How it differs from stillbirth
Miscarriage	Pregnancy loss earlier in gestation	Usually occurs before the gestational threshold used for stillbirth definition
Neonatal death	Death of a live-born baby within the first 28 days after birth	The baby is born alive, unlike stillbirth
Fetal growth restriction	Baby is not growing as expected in the womb	A risk factor for stillbirth, not the same outcome
Preeclampsia	Pregnancy complication involving high blood pressure and organ stress	Can increase stillbirth risk but is a separate diagnosis
Placental abruption	Placenta separates early from the uterus	Can cause stillbirth if severe but is one specific cause or complication

Questions to ask your doctor

Based on my history, is this pregnancy considered high risk for stillbirth?
Do I need extra ultrasounds or fetal monitoring?
What should I do if fetal movement decreases?
Do my blood pressure, blood sugar, weight, or medical conditions increase risk?
Is there anything in my medications or lifestyle that should change?
If we had a prior stillbirth, what testing is recommended before trying again?
Should my partner or I have genetic counseling or fertility testing?
Would earlier delivery lower risk in this pregnancy?

Myths and misconceptions

Myth: Stillbirth always happens without warning.

Not always. Some stillbirths occur suddenly, but others are preceded by reduced fetal movement, bleeding, growth problems, or abnormal prenatal testing.

Myth: A prior stillbirth means future pregnancies will end the same way.

No. A previous stillbirth can increase recurrence risk, but many people go on to have healthy pregnancies with appropriate evaluation and care.

Myth: If the mother feels fine, the pregnancy is definitely fine.

Not necessarily. Some placental or fetal problems do not cause obvious maternal symptoms. That is why prenatal visits and monitoring matter.

Myth: Stillbirth is always caused by something a parent did wrong.

False. Many cases involve medical, placental, or fetal factors beyond a parent's control. Blame is usually misplaced and harmful.

Myth: Men have no role in pregnancy outcomes like stillbirth.

That is too simplistic. Male factors usually are not the sole explanation, but paternal age, genetics, health, and environmental exposures can contribute to the broader reproductive picture.

FAQs

What week is stillbirth risk highest?

Risk changes throughout pregnancy and depends on individual circumstances. In uncomplicated pregnancies the absolute risk is low, but clinicians watch carefully near term and post-term, and even more closely when there are high-risk conditions.

Can decreased fetal movement mean stillbirth?

It can be a warning sign, which is why it should never be ignored. Reduced movement does not always mean stillbirth, but it does require prompt assessment.

Is stillbirth preventable?

Not always, but some causes are modifiable or can be detected early. Prenatal care, management of chronic disease, smoking cessation, and fetal monitoring can reduce risk in many pregnancies.

Does IVF increase stillbirth risk?

Pregnancies conceived with assisted reproductive technology may have different risk profiles, but the explanation is often complex and may reflect age, infertility causes, multiple gestation, and underlying health factors rather than IVF alone.

Does paternal age affect stillbirth risk?

It may contribute modestly in some studies, but maternal, placental, and fetal factors generally play larger roles. Paternal age is one part of a broader fertility and pregnancy-risk assessment.

Can stress cause stillbirth?

Routine psychological stress is not considered a direct proven cause of most stillbirths. Severe stress may affect health behaviors and pregnancy complications indirectly, but stillbirth usually involves more specific medical factors.

What tests are done after a stillbirth?

Often placental examination, fetal examination or autopsy, genetic testing, and selected maternal blood tests. The exact workup depends on the clinical situation and family preferences.

What is the risk of stillbirth after a previous stillbirth?

Recurrence risk is higher than average, but the exact number depends heavily on the cause of the earlier loss. A specialist can review the prior records and estimate risk more accurately for a future pregnancy.

Can poor sperm quality cause stillbirth?

Poor sperm quality is not a common direct explanation for stillbirth, but sperm DNA damage, genetic issues, and male health factors may contribute in some cases. If there is infertility or repeated pregnancy loss, a male-factor evaluation may be reasonable.