Definition and epidemiology
Stillbirth is fetal death occurring at or after 20 weeks of gestation (WHO uses ≥28 weeks or ≥1000 g for international comparisons; US definitions vary by state but commonly use 20 weeks). It is classified as:
- Early stillbirth: 20-27 weeks
- Late stillbirth: 28-36 weeks
- Term stillbirth: ≥37 weeks
Globally, the stillbirth rate is approximately 1 in 72 births (roughly 13.9 per 1000 total births), accounting for about 1.9 million stillbirths each year, with rates markedly higher in low-resource settings. In high-income countries the rate is approximately 3-5 per 1000 births. Disparities exist by race and socioeconomic status, with higher rates reported in Black women in the US compared with White women, likely reflecting a combination of biological and social determinants of health.
- Stillbirth = fetal death at or after 20 weeks gestation (WHO: ≥28 weeks for global comparisons)
- Decreased fetal movement is the most common presenting symptom
- Diagnosis requires absent cardiac activity on real-time ultrasound, ideally confirmed by two examiners
- Placental causes are the most commonly identified category; up to one-third remain unexplained
- Autopsy and placental histology are the single most valuable diagnostic tests
- Vaginal delivery is preferred over cesarean in most cases
- Give Rh immune globulin postpartum if mother is Rh-negative
- Prior stillbirth is the strongest risk factor for recurrence
Etiology and risk factors
Causes are often multifactorial; a substantial fraction remain unexplained even after full workup.
Fetal causes
- Chromosomal/genetic abnormalities
- Structural malformations
- Non-immune or immune hydrops
- Multiple gestation (especially monochorionic, twin-twin transfusion)
Placental causes (most common identifiable category)
- Placental insufficiency / fetal growth restriction
- Placental abruption
- Vasa previa, cord accidents (true knot, prolapse)
- Chorioamnionitis
Maternal causes
- Hypertensive disorders (chronic hypertension, preeclampsia)
- Diabetes mellitus (pregestational more than gestational)
- Obesity, advanced maternal age (>35), smoking, substance use
- Antiphospholipid syndrome and other thrombophilias
- Intrahepatic cholestasis of pregnancy
- Infection (parvovirus B19, syphilis, listeria, malaria in endemic areas)
- Prior stillbirth (strongest predictor of recurrence)
- Post-term pregnancy
Many stillbirths occur in pregnancies with no identifiable risk factor, which is why routine antenatal surveillance has limited sensitivity.
Pathophysiology
The common final pathway in most explained stillbirths is uteroplacental insufficiency leading to chronic fetal hypoxia, acidemia, and death. Mechanisms include:
- Impaired placentation: abnormal trophoblast invasion causes reduced uteroplacental blood flow, seen in preeclampsia and fetal growth restriction.
- Acute vascular events: abruption or cord accident causes sudden loss of oxygen/nutrient delivery.
- Infection: ascending or transplacental infection triggers fetal inflammatory response, sepsis, or direct organ damage (e.g., parvovirus-induced severe anemia and hydrops).
- Metabolic derangement: poorly controlled diabetes causes fetal hyperinsulinemia, macrosomia, and increased oxygen demand that the placenta cannot meet.
- Genetic/structural: lethal malformations or aneuploidy cause death independent of placental function.
In many cases, chronic subclinical placental dysfunction culminates in an acute hypoxic event, which is why isolated findings (e.g., a single abnormal Doppler) are hard to use for prediction.
Clinical features
- Maternal perception of decreased or absent fetal movement is the most common presenting symptom
- Absence of fetal heart tones on exam
- No pain in most cases; vaginal bleeding may occur if abruption is the cause
- Uterine size may be smaller than expected for dates (growth restriction) or normal
- Signs of underlying cause may be present: hypertension, edema (preeclampsia), fever (infection), pruritus/jaundice (cholestasis)
- Maceration (skin peeling, discoloration) on later ultrasound or at delivery suggests death occurred some time before presentation
- Rarely, disseminated intravascular coagulation (DIC) develops if the fetus is retained for weeks (consumptive coagulopathy)
Diagnosis
Diagnosis is confirmed by real-time ultrasound showing absent fetal cardiac activity, ideally confirmed by a second examiner. M-mode can document absence of cardiac motion.
Maternal workup (to identify cause and guide future pregnancy counseling)
| Test | Purpose |
|---|---|
| Kleihauer-Betke test | Detects fetomaternal hemorrhage |
| HbA1c | Screens for undiagnosed diabetes |
| Antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, anti-beta2-glycoprotein) | Thrombophilia workup |
| Parvovirus B19, syphilis serology | Infectious causes |
| Thyroid function | Associated endocrine disease |
| Toxicology screen | Substance use |
| Indirect Coombs/antibody screen | Alloimmunization |
Fetal/placental workup
- Autopsy (with parental consent) is the single most informative test
- Placental pathology (gross and histologic exam) identifies infarction, abruption, chorioamnionitis, villitis
- Genetic testing: karyotype or microarray (preferred, detects more abnormalities and does not require viable cells) on fetal tissue or amniotic fluid
- External and internal fetal examination for dysmorphic features
A standardized, complete workup identifies a probable cause in roughly 60-75% of cases; without it, many deaths are classified as unexplained.
Differential diagnosis
- Missed miscarriage (<20 weeks) — same mechanism (no cardiac activity) but earlier gestational age by definition
- Fetal demise from monochorionic twin complications (twin-twin transfusion, twin anemia-polycythemia sequence)
- Severe fetal growth restriction with ongoing viability — must distinguish from demise with Doppler and cardiac activity assessment
- Maternal sepsis/chorioamnionitis with viable fetus — fever and uterine tenderness without fetal demise
- Preeclampsia/eclampsia with live fetus — overlapping risk factor but distinct entity requiring urgent management
- Molar pregnancy — abnormal ultrasound findings but no normal fetal structure in complete mole
Management
Immediate management
- Confirm diagnosis with ultrasound (second confirmatory scan if any uncertainty)
- Provide the news with compassion, in a private setting, allowing time for questions
- Discuss mode of delivery: vaginal delivery is preferred and recommended in most cases, even with prior cesarean, unless specific contraindications exist
- Induction of labor is standard; agents include misoprostol and/or oxytocin, often preceded by cervical ripening. RCOG recommends mifepristone pretreatment before misoprostol, especially earlier in gestation, and this practice is increasingly used internationally; however, mifepristone is not uniformly available worldwide and is not FDA-labeled for this indication in the US, so protocols vary by country and institution
- Timing: delivery is generally recommended within 24-48 hours of diagnosis in uncomplicated cases, both for psychological reasons and because of the (low but real) risk of coagulopathy with prolonged retention
- Pain control and emotional support are integral to care
Peripartum workup
- Offer autopsy and placental pathology before delivery planning when possible
- Send placenta regardless of parental decision on fetal autopsy
- Offer genetic testing via karyotype/microarray
Postpartum care
- Lactation suppression counseling (if desired)
- Psychological support, bereavement counseling, and referral to support groups
- Rh immune globulin if mother is Rh-negative
- Thromboprophylaxis consideration given elevated VTE risk postpartum
Future pregnancy counseling
- Risk of recurrence depends on identified cause; overall recurrence risk is modestly increased compared with the general population
- Early referral to maternal-fetal medicine for high-risk pregnancies
- Low-dose aspirin for preeclampsia risk reduction in subsequent pregnancies if risk factors present
- Increased antenatal surveillance (growth scans, antenatal testing) in a subsequent pregnancy, though evidence for optimal protocols is limited
Guideline note: ACOG and RCOG both recommend vaginal delivery as first-line and support a full diagnostic evaluation, though specific test panels and cervical ripening protocols (e.g., mifepristone use) vary between societies and countries.
Complications and prognosis
- Maternal: coagulopathy (DIC) with prolonged fetal retention (rare with timely delivery), postpartum hemorrhage, infection, psychological sequelae including depression, anxiety, and post-traumatic stress
- Obstetric: increased risk of preterm birth, growth restriction, and stillbirth recurrence in future pregnancies, particularly if the underlying cause (e.g., diabetes, hypertension) persists
- Prognosis for future pregnancy: generally favorable with appropriate surveillance; most subsequent pregnancies result in a live birth, especially when a correctable or monitorable cause is identified
- Grief and mental health support should be offered for at least the following months, as the psychological impact can be prolonged
Causes of stillbirth — "PLACENTA": Placental insufficiency, Lethal anomalies, Abruption, Cord accident, Endocrine (diabetes), Nuchal/infection, Thrombophilia, Alloimmunization/Age (maternal)
Practice questions
1. A 32-year-old G2P1 woman at 34 weeks gestation presents reporting no fetal movement for the past day. Fetal heart tones cannot be detected by Doppler. Which of the following is the most appropriate next step to confirm the diagnosis?
2. A woman who had an intrauterine fetal demise at 28 weeks delivers vaginally. The placenta is sent for pathology, and parents decline fetal autopsy. Which single test provides the most additional diagnostic information in this scenario?
3. A 29-year-old woman at 31 weeks with confirmed intrauterine fetal demise asks about delivery options. She has one prior low transverse cesarean delivery. There is no evidence of placenta accreta, transverse lie, or other contraindication. What is the most appropriate recommendation?
Frequently asked questions
What causes stillbirth?
The most common identifiable causes are placental problems (insufficiency, abruption), followed by fetal chromosomal or structural abnormalities, maternal conditions like diabetes and hypertension, cord accidents, and infections. Despite a thorough workup including autopsy and placental pathology, no definite cause is found in roughly a quarter to a third of cases.
What are the first signs of stillbirth?
The earliest and most common sign is a noticeable decrease or complete absence of fetal movement. Some women have no warning symptoms at all. Less commonly, vaginal bleeding or abdominal pain may occur if the cause is placental abruption. Any concern about reduced movement warrants prompt evaluation with fetal heart rate monitoring and ultrasound.
How is stillbirth diagnosed?
Stillbirth is diagnosed by real-time ultrasound showing no fetal cardiac activity, ideally confirmed by a second examiner to avoid error. After confirmation, further testing (maternal blood work, placental pathology, fetal autopsy, and genetic testing) is offered to try to identify the underlying cause and guide future pregnancy counseling.
Can stillbirth be prevented or is it curable?
Stillbirth itself cannot be reversed once it occurs, but many risk factors are modifiable, including controlling diabetes and hypertension, avoiding smoking, monitoring fetal growth, and increased surveillance in high-risk pregnancies. Prevention strategies reduce but cannot eliminate risk, since a substantial proportion of cases have no identifiable preventable cause.
Stillbirth vs miscarriage — what is the difference?
The key difference is gestational age at the time of fetal death: miscarriage (spontaneous abortion) refers to pregnancy loss before 20 weeks, while stillbirth refers to fetal death at or after 20 weeks. The underlying causes overlap somewhat but miscarriage is more often due to chromosomal abnormalities, while stillbirth more often involves placental dysfunction.
Key drugs
Related conditions and differentials
Sources and further reading
StatPearls (NCBI Bookshelf)MedlinePlusWHO ICD-10: P95
Educational content for medical students, prepared by the WhiteCoat Pro editorial team with AI assistance; every page is reviewed by a second AI model for factual errors. It is not medical advice and does not replace the product label, local guidelines or a clinician.