Estetrol: A New Choice for Contraception

Area of Science:

• Endocrinology
• Pharmacology
• Reproductive Health

Background:

• Estetrol (E4) is a natural estrogen produced by the fetal liver.
• E4 acts as a selective estrogen receptor modulator with moderate affinity for ERα and ERβ.
• Clinical studies suggest E4's potential use in combined oral contraceptives (COCs).

Purpose of the Study:

• To review current knowledge on E4-containing contraceptives.
• To evaluate the efficacy and safety of E4/drospirenone (DRSP) COCs.
• To compare E4/DRSP with ethinylestradiol (EE)-containing COCs.

Main Methods:

• Review of clinical studies and research on E4 and E4/DRSP contraceptives.
• Analysis of data on ovulation inhibition, endometrial effects, bleeding patterns, and cycle control.
• Assessment of metabolic and safety profiles, including lipid levels, liver function, and venous thromboembolism risk.

Main Results:

• E4/DRSP COCs demonstrate high acceptability, tolerability, and user satisfaction.
• E4/DRSP effectively inhibits ovulation and impacts endometrium similarly to EE-containing COCs.
• Low-dose E4/DRSP (15mg/3mg) shows promising cycle control and bleeding patterns.
• The combination has limited effects on metabolic parameters and may offer a lower VTE risk than EE-based COCs.

Conclusions:

• E4/DRSP represents a novel contraceptive option with a potentially favorable safety profile.
• Further large-scale studies are necessary to fully elucidate cardiovascular safety and long-term user satisfaction.
• E4/DRSP warrants consideration as an alternative to traditional estrogen-containing COCs.