Miscarriage occurs in up to one third of pregnancies.
Described as threatened, inevitable, incomplete, complete, missed, or recurrent miscarriage.
Presence of pain, hypotension, tachycardia, and/or anaemia warrants exclusion of a life-threatening differential diagnosis such as an ectopic pregnancy.
Serial serum beta hCG titres and a trans-vaginal ultrasound scan aid in diagnosis.
Medical or surgical uterine evacuation is recommended when the pregnancy is no longer viable. The patient may also be offered a choice of conservative management unless there is profuse, heavy, and persistent bleeding.
The experience of a miscarriage is associated with a psychological impact of varying intensity in the short or long term, or both.
Miscarriage is an involuntary, spontaneous loss of a pregnancy before 20-24 completed weeks. The gestational threshold for the definition varies between countries: in the US it is usually 20 weeks (but may vary in different states), whereas in the UK, the Royal College of Obstetricians and Gynaecologists defines it as 24 weeks. After these differing cut-offs, the loss would be defined as a stillbirth. Miscarriage is associated with unprovoked vaginal bleeding with or without suprapubic pain. The commonly used term, abortion, is unpopular with women who are uncomfortable with a suggestion that it follows an intentional attempt to terminate the pregnancy.
History and exam
Key diagnostic factors
- presence of risk factors
- vaginal bleeding with or without clots
Other diagnostic factors
- suprapubic pain
- low back pain
- recent post-coital bleed
- uterine structural abnormality
- history of trauma
- older age
- uterine malformation
- bacterial vaginosis
- parental chromosomal anomaly
- vitamin D deficiency
- previous spontaneous/induced miscarriage
- infertility/assisted conception
- non-steroidal anti-inflammatory drugs (NSAIDs)
- thyroid dysfunction
- diabetes mellitus
1st investigations to order
- trans-vaginal ultrasound scan
- serum beta hCG titres
Investigations to consider
- transabdominal ultrasound scan
- serum progesterone
- urine pregnancy test
- rhesus blood group
- lupus anticoagulant/anticardiolipin antibodies
- pelvic ultrasound
- cytogenetic analysis on products of conception
- parental karyotype
- vaginal swab
Ida Muslim, MBChB, MRCOG
Consultant Obstetrician & Gynaecologist
The Women’s Centre
Gloucestershire Royal Hospital
IM declares that she has no competing interests.
Jothi Doraiswamy, MBBS, MRCOG
Consultant in Obstetrics and Gynaecology
Gloucestershire Royal Hospital
JD declares that she has no competing interests.
Dr Ida Muslim and Dr Jothi Doraiswamy would like to gratefully acknowledge Dr Isaac Babarinsa and Professor Tim Draycott, previous contributors to this topic.
IB and TD declare that they have no competing interests.
Jo Trinder, MD
Consultant Obstetrician and Gynaecologist
St Michael's Maternity Wing
Bristol Royal Infirmary
JT is the primary author of one randomised controlled trial cited in this topic. This trial was funded by an NHS Research and Development Grant and a donation from Exelgyn, the manufacturer of misoprostol. JT has accepted honoraria for speaking to groups of midwives and doctors about miscarriage management.
John Bachman, MD
Consultant in Family Medicine
Parker D Sanders and Isabella Sanders Professor of Primary Care
JB declares that he has no competing interests.
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