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This article is for academic and educational purposes only, intended for Pharm.D students studying anatomy and physiology. It does not promote or discuss explicit content but focuses on medical and pharmaceutical knowledge.
Introduction
Sex hormones include estrogens, progesterone and androgens. They regulate reproductive functions in males and females. These hormones are widely used in medicine, especially for contraception, hormone replacement therapy and treatment of various reproductive disorders. Oral contraceptives are the most effective and widely used reversible family-planning method.
Estrogens
Estrogens are female sex hormones mainly produced by the ovaries. They promote development of female reproductive organs and secondary sexual characteristics. They also regulate menstrual cycle and maintain bone and cardiovascular health.
Common Estrogens
- Estradiol
- Ethinyl estradiol
- Mestranol
Therapeutic Uses
- Hormone replacement therapy in menopause
- Primary hypogonadism
- Dysfunctional uterine bleeding
- Component of oral contraceptives
Adverse Effects
- Nausea and vomiting
- Breast tenderness
- Risk of thromboembolism
- Gallbladder disease
Progesterone
Progesterone prepares the uterus for pregnancy and maintains pregnancy. Synthetic forms of progesterone are called progestins. They are combined with estrogen in oral contraceptives and also used alone.
Common Progestins
- Medroxyprogesterone acetate
- Norethisterone
- Levonorgestrel
- Desogestrel
Therapeutic Uses
- Contraception
- Endometriosis
- Hormone replacement therapy
- Dysmenorrhea
Adverse Effects
- Weight gain
- Mood changes
- Acne and oily skin
- Irregular bleeding
Androgens
Androgens are male sex hormones, mainly testosterone. They maintain male reproductive organs, muscle mass and secondary sexual characteristics.
Therapeutic Uses
- Male hypogonadism
- Delayed puberty
- Wasting in chronic illness
Adverse Effects
- Acne
- Increased body hair
- Liver disorders (from synthetic androgens)
- Edema
Oral Contraceptives
Oral contraceptives prevent pregnancy mainly by stopping ovulation. They may also thicken cervical mucus and make the endometrium unsuitable for implantation. They are classified into combined pills and progestin-only pills.
1. Combined Oral Contraceptives (COCs)
These contain both estrogen and progestin. They are the most commonly used contraceptive pills.
Mechanism of Action
- Inhibit ovulation (main action)
- Thicken cervical mucus → prevents sperm entry
- Make endometrium unsuitable for implantation
Types
- Monophasic pills: Same dose of hormones in all tablets
- Biphasic and triphasic pills: Varying hormone doses to mimic natural cycle
Common Formulations
- Ethinyl estradiol + Levonorgestrel
- Ethinyl estradiol + Desogestrel
Advantages
- Highly effective when taken regularly
- Regulates menstrual cycle
- Reduces dysmenorrhea
- Lowers risk of ovarian and endometrial cancer
Adverse Effects
- Nausea
- Headache
- Breast tenderness
- Weight gain
- Risk of venous thrombosis (rare)
Contraindications
- Pregnancy
- History of thrombosis
- Severe hypertension
- Migraine with aura
- Smokers above 35 years
2. Progestin-Only Pills (Mini Pills)
These pills contain only progestin and are useful for women who cannot take estrogen.
Mechanism of Action
- Thickens cervical mucus
- Suppresses ovulation (less consistently than COCs)
- Makes endometrium unsuitable for implantation
Uses
- Breastfeeding women
- Women with risk of thrombosis
- Those unable to tolerate estrogen
Disadvantages
- Irregular menstrual bleeding
- Must be taken daily at the same time
3. Emergency Contraceptives
Used after unprotected intercourse to prevent pregnancy.
Types
- Levonorgestrel 1.5 mg single dose
- Ulipristal acetate
- High-dose combined pills (Yuzpe method)
Mechanism
- Delays ovulation
- Prevents fertilization
- May prevent implantation
Adverse Effects
- Nausea
- Vomiting
- Irregular bleeding
4. Long-Acting Reversible Contraceptives (LARCs)
These are non-oral options providing long-term contraception.
Types
- Implants: Levonorgestrel implants
- Injectables: Depot medroxyprogesterone acetate
- Intrauterine devices: Copper IUD, Hormonal IUD
Detailed Notes:
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