Why it is performed
- Confirm pregnancy.
- Assess very early progression with serial measurements.
- Support evaluation of pain or bleeding in early pregnancy, always with clinical assessment.
- Monitor decline after pregnancy loss, ectopic pregnancy or selected procedures.
How it is performed
β-hCG is measured in a sample. In early pregnancy, serial values may be more useful than a single result. Ultrasound is timed according to gestation, symptoms and concentration.
Preparation
- Provide last menstrual period, fertility treatment and any hCG administration.
- Do not wait for testing if there is severe pain, fainting, heavy bleeding or shoulder pain: urgent assessment is needed.
- A very early urine test may be negative because concentration is too low.
How Askabide processes it
At Askabide
β-hCG may be measured by fluorescence immunoassay on ichroma II with an active, quality-controlled cartridge. Unexpected results are repeated or confirmed by another method when appropriate.
The main analytical phase is performed in the centre’s laboratory, subject to availability and validation.
Results and indicative intervals
Intervals vary by method, analyser, reagent, units, age, sex, pregnancy, menstrual-cycle phase and reference population. The valid interval is the one printed on the laboratory report.
| Parameter or result | Indicative reference | How it is interpreted |
|---|---|---|
| Not pregnant | Habitualmente <5 mUI/mL | 5–25 is commonly indeterminate and may require repeat testing. |
| Compatible with pregnancy | Habitualmente ≥25 mUI/mL | Does not locate the pregnancy or confirm viability by itself. |
| Serial change | Interpretation depends on starting value and time | There is no exact universal doubling rule for every pregnancy. |
Important limitations
- A positive β-hCG does not show where the pregnancy is located.
- A single value does not confirm normal progression.
- hCG-containing medicines and, rarely, assay interference can alter results.
- Ectopic pregnancy may show slow rises, falls or apparently normal values.