The quality of evidence (I-III) and classification of recommendations (A-E, I) are defined at the end of the "Major Recommendations" field.
- Pregnant women should be offered a routine second trimester ultrasound between 18 and 22 weeks' gestation. (II-2B)
- Second trimester ultrasound should screen for the number of fetuses, the gestational age, and the location of the placenta. (II-1A)
- Second trimester ultrasound should screen for fetal anomalies. (II-2B)
The table below shows the recommended content of the ultrasound report, but other information may be provided in such consultations.
Table: Content of a Complete Obstetrical Ultrasound Report
| Category |
Required Information |
| Patient demographic information |
- Patient name, second patient identifier (birth date, hospital identifier, health insurance number)
- Indication for consultation
- Requesting physician/caregiver (preferably with contact information)
- Starting date of last normal menstrual period (LNMP)
- Examination date
- Date of written report
- Name of interpreting physician
|
| Number of fetuses and indications of life |
- Presence of cardiac activity for each fetus
- If multiple gestation: chorionicity and amnionicity should be reported
|
| Biometry |
Should be reported all in millimetres or in centimetres along with equivalent estimated gestational age for:
- Biparietal diameter
- Head circumference
- Abdominal circumference
- Femur length
Should be reported in millimetres if abnormal:
- Nuchal fold
- Cisterna magna
- Cerebellar diameter
- Lateral ventricle width
|
| Fetal anatomy |
Should be reported as: normal OR abnormal (with details) OR not seen, with explanation
Should be reported for:
- Cranium
- Cerebral ventricles, cavum septi pellucidi, the midline falx, the choroid plexus
- Posterior fossa: cisterna magna, cerebellum
- Face: orbits, lips
- Spine
- Chest
- Cardiac four-chamber view
- Cardiac outflow tracts
- Heart axis
- Cardiac situs
- Stomach
- Bowel
- Kidneys
- Bladder
- Abdominal cord insertion
- Number of cord vessels
- Upper extremities and presence of hands
- Lower extremities and presence of feet
|
| Amniotic fluid amount |
Should be reported as: normal OR increased OR decreased OR absent |
| Placenta |
Position should be reported as well as relationship to the cervical os |
| Maternal anatomy uterus, ovaries, cervix, bladder |
Should be reported as:
- Normal OR abnormal with details OR not seen
|
Definitions:
Levels of Evidence*
I: Evidence obtained from at least one properly designed randomized controlled trial.
II-1: Evidence obtained from well-designed controlled trials without randomization.
II-2: Evidence obtained from well-designed cohort (prospective or retrospective) or case-control studies, preferably from more than one center or research group.
II-3: Evidence obtained from comparisons between times or places with or without the intervention. Dramatic results in uncontrolled experiments (such as the results of treatment with penicillin in the 1940s) could also be included in this category.
III: Opinions of respected authorities, based on clinical experience, descriptive studies, or reports of expert committees.
Grades of Recommendation**
A. There is good evidence to recommend the clinical preventive action.
B. There is fair evidence to recommend the clinical preventive action.
C. The existing evidence is conflicting and does not allow to make a recommendation for or against use of the clinical preventive action; however, other factors may influence decision-making.
D. There is fair evidence to recommend against the clinical preventive action.
E. There is good evidence to recommend against the clinical preventive action.
I. There is insufficient evidence (in quantity or quality) to make a recommendation; however, other factors may influence decision-making.
*The quality of evidence reported in these guidelines has been adapted from The Evaluation of Evidence criteria described in the report of the Canadian Task Force on Preventive Health Care.
**Recommendations included in these guidelines have been adapted from the Classification of Recommendations criteria described in the report of the Canadian Task Force on Preventive Health Care.
