OVERVIEW OF FERTILITY CONTROL
| Extremely | Very | Less | |
| Effective | Effective | Effective | |
| IUDs | Oral contraceptives | Male condom | |
| Female condom | |||
| DMPA | |||
| Patch | Cervical cap | ||
| Implants | |||
| Ring | Diaphragm | ||
| Sterilization | |||
| Withdrawal | |||
Figure II-9-1. Contraception
BARRIER-SPERMICIDAL METHODS
A 16-year-old adolescent comes to the family planning clinic requesting contraception. She has heard about the diaphragm and wonders if it would be appropriate for her.
Mechanisms of Action. These are locally active devices preventing entry of sperm in throughthe cervix, thus preventing pregnancy.
Advantages. Barrier methods become increasingly effective with advancing age and the associ-ated natural decline in fertility. They do protect against some STDs. They do not have systemic side effects.
Disadvantages. Failure rate approaches 20%. They are coitally dependent, requiring a decisionfor each use, thus decreasing spontaneity. Barrier methods have no impact on excessive men-strual flow or excessively painful menses.
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Specific Types
• Condoms. These are penile sheaths that must be placed on the erect penis. No indi-vidual fitting is required. They are the most common barrier contraceptive method used.
• Vaginal diaphragm. This is a dome-shaped device placed in the anterior and posteriorvaginal fornices holding spermicidal jelly against the cervix. It can be placed an hour before intercourse. Individual fitting is required. If too large a size is used, it can result in urinary retention.
• Spermicides. The active ingredient is nonoxynol-9, a surface-active agent that disruptscell membranes, thus the possible side effect of genital membrane irritation. These can take the form of jellies or foams placed into the vagina.
STEROID CONTRACEPTION
A 44-year-old woman, gravida 4 para 4, presents with questions about oral steroid contraception. She uses a diaphragm but is worried about contraceptive failure. She also expresses concern that her menses have become slightly heavier and more painful. She does not smoke and has no other medical problems.
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Mechanisms of Action. These include inhibition of the midcycle luteinizing hormone (LH) surge,thus preventing ovulation; alteration of cervical mucus making it thick and viscid, thus retarding sperm penetration; and alteration of endometrium inhibiting blastocyst implantation.
Table II-9-1. Mechanism of Action of Steroid Contraception
| Pituitary | ↓ LH surge |
| Ovary | ↓ ovulation |
| Endometrium | Atrophy |
| Cervix | Hostile mucus |
Estrogen-Mediated Metabolic Effects. These include fluid retention from decreased sodiumexcretion; accelerated development of cholelithiasis; increase in hepatic protein production (e.g., coagulation factors, carrier proteins, angiotensinogen); healthy lipid profile changes (increase in high-density lipoproteins [HDL]; decrease in low-density lipoproteins [LDL]); and increased venous and arterial thrombosis.
Progestin-Mediated Metabolic Effects. These include mood changes and depression fromdecreased serotonin levels; androgenic effects (e.g., weight gain, acne); and unhealthy lipid profile changes (decreased HDL, increased LDL).
Absolute Contraindications. These include pregnancy; acute liver disease; history of vasculardisease (e.g., thromboembolism, deep venous thrombosis [DVT], cerebrovascular accident [CVA], systemic lupus erythematosus [SLE]); hormonally dependent cancer (e.g., breast); smoker ≥35; uncontrolled hypertension; migraines with aura; diabetes mellitus with vascular disease; and known thrombophilia.
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Relative Contraindications. These include migraine headaches, depression, diabetes mellitus,chronic hypertension, and hyperlipidemia.
Noncontraceptive Benefits. These include decreased ovarian and endometrial cancer; decreaseddysmenorrhea and dysfunctional uterine bleeding; and decreased PID and ectopic pregnancy.
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