Summary
Definition
History and exam
Key diagnostic factors
- scarred uterus
- presence of other risk factors
- painless vaginal bleeding
- absence of cervical/vaginal causes of bleeding on speculum examination
Other diagnostic factors
- previous ultrasound anomaly in first trimester
- lack of uterine tenderness
- low blood pressure and tachycardia
Risk factors
- advanced maternal age
- multiple previous pregnancies
- smoking
- previous miscarriage
- previous induced abortion
- other placental abnormalities
- short interpregnancy intervals
- illicit drug use
- uterine scarring (most commonly due to prior cesarean section)
- infertility treatments
- prior placenta previa
Diagnostic investigations
1st investigations to order
- uterine ultrasound with color flow Doppler analysis
- CBC
- type and crossmatch
Investigations to consider
- MRI placenta
- INR/PTT, fibrinogen, and fibrinogen degradation products
- Kleihauer-Betke test
Treatment algorithm
bleeding with unknown placental position
bleeding with known placenta previa
placenta previa with no bleeding
with miscarriage or elective termination
Contributors
Authors
Janet R. Albers, MD

Professor
Department Chair
Family and Community Medicine
Southern Illinois University School of Medicine
Springfield
IL
Disclosures
JRA declares that she has no competing interests.
Thomas H. Miller, MD
Professor
Clinical Family and Community Medicine
Associate Chairman - Western Region
Southern Illinois University School of Medicine
Springfield
IL
Disclosures
THM declares that he has no competing interests.
Acknowledgements
Dr Janet R. Albers and Dr Thomas H. Miller would like to gratefully acknowledge Dr Robert Ewart and Dr Matthew Hagermeyer, previous contributors to this topic.
Disclosures
RE and MH declare that they have no competing interests.
Peer reviewers
Yosra Tahir Jarjees, MD
Assistant Professor
Head of Department of Obstetrics and Gynecology
Mosul College of Medicine
Mosul
Iraq
Disclosures
YTJ declares that he has no competing interests.
John Bachman, MD
Consultant in Family Medicine
Parker D Sanders and Isabella Sanders Professor of Primary Care
Rochester
MN
Disclosures
JB declares that he has no competing interests.
Differentials
- Normal labor
- Placental abruption
- Miscarriage
More DifferentialsGuidelines
- Guideline no. 402: diagnosis and management of placenta previa
- Guideline no. 402: diagnosis and management of placenta previa
More GuidelinesPatient leaflets
Premature labor
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