1. Excitement / Foreplay – longest phase
- both couples need to be aroused
- occurs with physical and psychologic stimulation that causes parasympathetic nerve stimulation
- this leads to arterial dilation and venous constriction in the genital area
- vasocongestion and increasing muscular tension
- in women, clitoris increases in size and mucoid fluid to appear on vaginal walls as lubrication
- the vagina widens in diameter and increases in length
- the breast nipples become erect. Reddening of the labia minora and vaginal wall occur
- in men, erction occurs; there is scrotal thickening and elevation of the testes
- in both sexes, there is an increase in heart rate and respiratory rate and blood pressure
2. Plateau – starting to escalate
- it is reached just before orgasm
- in women, clitoris is drawn forward and retracts under the clitoral prepuce; the lower part of the vagina becomes extremely congested and there is increased nipple engorgement.
- in men, the vasocongestion leads to full distention of the penis
- heart rate increases to 100 to 175bpm and respiratory rate to approximately 40cpm
3. Orgasm – peak of sexual response cycle
- occurs when stimulation proceeds through the plateau stage to a point at which the body suddenly discharges accumulated sexual tension
- vigorous contraction of muscles in the pelvic area expels / dissipates blood and fluid from the area of congestion
start of ejaculation
- for women, the average number of contractions is from 8 – 15 at intervals of one every 0.8 seconds
- in men, muscle contractions surrounding the seminal vessels and prostate project semen into the proximal urethra. Theses contractions are followed immediately by 3 – 7 propulsive ejaculatory contractions, occurring at the same time interval as in women which force semen from the penis.
- As the shortest stage in the sexual response cycle, orgasm is usually experienced as intense pleasure affecting the whole body, not just the pelvic area
- It is also highly personal experience; descriptions vary greatly from person to person
4. Resolution – internal and external genital organs return to an unaroused state (organs go back to normal size)
- Refractory period -> women do not have refractory period; they can have sex again after orgasmic phase
-> but men cant have another erection because they have refractory period
-> only after 30mins could men have sex again and have an erection; men cant have erection after orgasmic phase
- For both men and women, this period generally takes 30 minutes
