Estriol (E3)

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.