NATURAL FAMILY PLANNING—PERIODIC ABSTINENCE
This method is based on avoiding sexual intercourse around the time of predicted ovulation. It assumes the egg is fertilizable for 12 to 24 hours and sperm is capable of fertilizing the egg for 24 to 48 hours. Requires high degree of discipline from both sexual partners.
Methods used. Prediction or identification of ovulation may inferred from: menstrual records,basal body temperature charting (temperature rise from thermogenic effect of progesterone), change in cervical mucus from thin and watery to thick and sticky (reflects the change from estrogen dominance preovulation to progesterone dominance postovulation).
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USMLE Step 2 l Gynecology
Advantages. Inexpensive. Readily available. No steroid hormonal side-effects. May be preferredfor religious reasons.
Disadvantages. Inaccurate prediction of ovulation. High failure rate because of human frailitiesand the passions of the moment.
COITUS INTERRUPTUS
In this practice, also known as withdrawal or pull-out method, the man withdraws his penis from the woman’s vagina prior to orgasm and ejaculation. It is one of the oldest contraceptive methods described.
Advantages: Readily available. Inexpensive. Free of systemic side effects.
Disadvantages: High failure rates. No protection against STDs. High degree of disciplinerequired. Semen can enter vagina and cervical mucus prior to ejaculation.
VAGINAL DOUCHE
With vaginal douche, plain water, vinegar and other products are used immediately after orgasm to theoretically flush semen out of the vagina. It has a long history of use in the United States.
Advantages: None.
Disadvantages: High failure rates. No protection against STDs. Sperm can enter the cervical mucus within 90 seconds of ejaculation.
LACTATION
With lactation, elevated prolactin levels with exclusive breastfeeding inhibit pulsatile secretion of GnRH from the hypothalamus. Effectiveness is dependent on the frequency (at least every 4-6 hours day & night) and intensity (infant suckling rather than pumping) of milk removal.
Advantages: Enhanced maternal and infant health, bonding, and nutrition. Readily available.
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Inexpensive. Needs no supplies. Free of systemic side effects. Acceptable to all religious groups.
Disadvantages: High failure rate if not exclusively breastfeeding. Reliable for only up to6 months. No protection against STDs.
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Chapter 9 l Fertility Control
STERILIZATION
A 38-year-old multipara has completed her childbearing and is requesting sterilization. All 3 of her children were delivered vaginally. She has no medical problems and is in good health. General and pelvic examination is unremarkable.
Mechanisms of Action. These are surgical procedures usually involving ligation of either thefemale oviduct or male vas deferens. After the procedure is performed, there is nothing to forget and nothing to remember. They are to be considered permanent and irreversible.
Tubal Ligation. Destruction or removal of a segment of the oviduct is performed in an operat-ing room through a transabdominal approach usually using a laparoscopy or minilaparotomy. Failure rate is 1 in 200. This is the most common modality of pregnancy prevention in the United States. If the procedure fails and pregnancy results, an ectopic pregnancy should be ruled out.
Vasectomy. Destruction or removal of a segment of vas deferens is performed as an outpatientprocedure using local anesthesia. Failure rate is 1 in 500. A successful procedure can be con-firmed by absence of sperm on a semen specimen obtained 12 ejaculations after the surgery. Sperm antibodies can be found in 50% of vasectomized patients.
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Human Sexuality 10
HUMAN SEXUAL RESPONSE CYCLE
A 31-year-old woman, mother of 4 children, comes to the office stating she has little interest in sexual intercourse with her husband for the past year. She says sex is painful, but she is able to experience orgasm occasionally. She has had no other sexual partners than her husband. These problems are affecting her marriage. She had a tubal sterilization procedure performed after her last delivery 2 years ago. Medications include thyroid replacement and fluoxetine.
Linear Model
Desire. In both women and men the desire for sexual activity is also known as libido. Desire ismaintained by a balance between dopamine stimulation and serotonin inhibition. The threshold of response is determined by androgens, especially testosterone. This is true for women as well as men.
Excitement. This phase is also known as arousal. It is mediated by parasympathetic connectionsto the pelvic organs and results in vascular engorgement. Arousal in women is generally slower, responds more to touch and psychic stimuli, and is manifested by vaginal lubrication. Arousal in men is generally faster, responds more to visual stimuli, and is manifested by penile erection.
Plateau. This phase entails progression and intensification of the excitement phase. The length ofthis phase is variable. The neural pathway and physiologic mechanism is the same as excitement.
Orgasm. This phase is mediated by sympathetic connections resulting in reflex tonic-clonic muscle contractions of the pelvic floor followed by contractions of the uterus. Women havemore individual orgasmic variability than men. A unique characteristic of women is the potential for consecutive multiple orgasms.
Resolution. This phase is marked by a return to basal physiologic state with reversal of vaso-congestion and muscle tension. Resolution tends to be faster for men and slower for women.
Refractory Phase. This is a unique characteristic of men and is the period of inability to bearoused before another orgasm. It frequently varies directly with the age of the man.
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USMLE Step 2 l Gynecology
Circular Relational Model
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