Estriol (E3; estriol) is the natural form of the female sex hormone. It is formed from estradiol. Unlike estradiol, estriol dissociates quickly from the receptor, which means it is only weakly effective and has a short half-life.
It is used primarily to assess the fetoplacental unit in pregnancy.
The procedure
Material needed
- Blood serum
Preparation of the patient
- No preparation necessary
Disruptive factors
- None known
Normal values pregnancy
| Week of pregnancy (SSW) | Normal values in μg/l |
| 28.-31. | 2,5-10,0 |
| 32.-33. | 3,5-12,0 |
| 34.-35. | 4,0-13,0 |
| 36.-37. | 5,0-17,0 |
| 38.-40. | 6,0-25,0 |
Indications
- Abortus imminens (threatened abortion).
- Suspicion of trisomy 21 (Down syndrome), for example, in the context of triple diagnostics [1st trimester (third trimester of pregnancy)].
- Suspicion of placental insufficiency (malfunction of the placenta with subsequent restriction of the supply of the unborn child) for example due togestosis [3rd trimester; no longer common diagnostics].
Interpretation
Interpretation of increased values
- Multiple pregnancy
Interpretation of decreased values (estriol is meaningful only after multiple close-meshed determinations!).
- Placental insufficiency (malfunction of the placenta with subsequent restriction of the supply of the unborn child) because of: Maternal (lying with the mother) causes.
- Diabetes mellitus
- Gestosis (generic term for pregnancy-related diseases).
- Hypertension (high blood pressure)
- Hypoxia (lack of oxygen supply)
- Placental infection (infection of the placenta).
- Transmission
- Malnutrition
- Smoking
Fetal (lying with the child) causes
- Malformations e.g. anencephaly (“without brain“).
- Transplacental infections (infection coming through the placenta infects the child).
Other notes
- When interpreting the measured values must always take into account the exact time of pregnancy
- According to the KV, the determination of estriol is not a service reimbursable under the EBM. Justification: The performance is no longer timely.