Progesterone
Overview
Progesterone is a steroid hormone primarily produced by the ovaries, placenta, and adrenal glands, measuring levels that reflect ovarian function, pregnancy maintenance, and menstrual cycle phases. It plays a key role in preparing the uterine lining for implantation and sustaining early pregnancy by promoting endometrial growth and suppressing uterine contractions. Elevated levels indicate ovulation, luteal phase, or pregnancy, while low levels may signal anovulation, luteal phase deficiency, or menopause; clinically, it helps assess fertility, monitor pregnancies, and diagnose hormonal disorders.[openbiomarkerjournal]
Clinical Use Cases
- Evaluating ovulation and luteal phase adequacy in infertility workups.
- Monitoring early pregnancy viability and risk of miscarriage.
- Assessing causes of amenorrhea or abnormal uterine bleeding.
- Supporting diagnosis of ectopic pregnancy or corpus luteum insufficiency.
- Guiding progesterone supplementation in assisted reproduction.
Specimen Types
- Serum (most common).
- Plasma.
- Whole blood (less frequent).
- Saliva (for research or home testing).
- Amniotic fluid (prenatal assessment).
Measurement Methods
- Immunoassays (e.g., ELISA, chemiluminescent immunoassay).
- Radioimmunoassay (RIA, high sensitivity).
- Liquid chromatography-tandem mass spectrometry (LC-MS/MS, gold standard).
- Automated analyzers in clinical labs.
Test Preparation and Influencing Factors
- Time collection mid-luteal phase (days 21-23) for ovulation assessment.
- No fasting required, but avoid stress or vigorous exercise before draw.
- Influenced by pregnancy, oral contraceptives, hormone replacement therapy.
- Diurnal variation minimal, but levels fluctuate with menstrual cycle.
- Recent fertility treatments or ovulation induction can elevate results.
Synonyms
- P4.
- Pregn-4-ene-3,20-dione.
- Luteal hormone.
- Corpus luteum hormone.