Suo yang (Koro):
The Genital Retraction Syndrome

Koro, or genital retraction syndrome (GRS) is one of the most colorful of the culture-bound syndromes and has accordingly received attention disproportionate to its actual number of cases. Genital retraction syndrome comes in two major varieties: the Malaysian/Indonesian version, ethnographically called koro and known locally under several names; and the Chinese version, found primarily in South China or in ethnic Chinese of South Chinese origin, where it is known by various local phrases meaning "shrinking penis". Numerous isolated cases of a similar syndrome have been reported worldwide.

The individual afflicted with genital retraction syndrome believes that his or her genitals (or in the case of women, breasts and/or genitals) are retracting into the body. Such a belief would be frightening enough, but local tradition adds the warning that such an occurrence is usually fatal. The majority of persons with GRS are male; cases are reported to occur in women, at least in the Malaysian version, but are much more rare. A typical episode will occur when a man goes to urinate in the cold or while emotionally upset (often due to guilt over masturbation or frequenting prostitutes, while concerned about his sexual performance, or after a fight with his wife) and observes that his penis is becoming smaller, a condition known medically as hyperinvolution. Remembering the dangers of a shrinking penis, the man grabs his genitals before they can retract into his body, and calls for help. If no one is around to help hold onto his penis, the individual may use mechanical devices to keep the penis from retracting, including cords, chopsticks, clamps, or small weights. Episodes of GRS may strike the same indvidual repeatedly, and epidemics of GRS have been noted, most famously the great koro epidemic in Singapore in 1967.

The bulk of the literature has taken GRS as a purely subjective phenomenon, and much ink has been used in speculations on psychoanalytic explanations. In contrast to this psychoanalytic tradition, James Edwards (in Simons & Hughes, 1984:169-191) points out that there are physical events which could give rise to beliefs in GRS. Male genitals shrink on exposure to the cold, or in anxious and fearful emotional states. Penes may be displaced into the scrotum or abdominal cavity by injury, and can appear to be shrunken or partially retracted due to illness, obesity, or in victims of drowning. He also reports (p. 182) the strange case of a Russian man whose penis spontaneously retracted into his abdomen (it re-emerged by the next day, and did not repeat its disappearing act.) Several articles on koro appear in urological journals, and report that the syndrome is occasionally found in persons with anatomical abnormalities.

These criticisms of the case analyses aside, GRS cases seem to be similar in many ways to the Western category of panic attack, with sexual elaborations. It seems probable that, in a culture where sexual anxiety is high and stories exist of death by genital retraction, a man in the right frame of mind could panic at the observation that his genitals are shrinking in response to cold or anxiety. Case studies have not typically reported actual shrinkage of penes, and the majority of damage to the individuals has resulted from over-enthusiastic attempts to restrain the penis from retracting. Therapy consists mainly of patient education on reproductive anatomy, and reassurance that the penis is not in danger of disappearing.

A typical case study follows:

H.K.F., a male Chinese, aged 34...was at a cinema show when he felt the need to micturate. He went out to the latrine in the foyer, and as he was easing himself, he suddenly felt a loss of feeling in the genital region, and straightaway the thought occurred to him that he was going to get penile retraction. Sure enough, he noticed that the penis was getting shorter...He felt cold in the limbs, and was weak all over, and his legs gave way under him. So he sat on the floor, all this time holding onto his penis. About half an hour later, the attacks abated. He went to see a medical specialist and was prescribed some pills...At 24 years of age, he exposed himself to a prostitute, and was infected with gonorrhea, and since then he has abstained himself. He heard of shook yong from his friends and also heard about some fatalities during intercourse previous to the attack.
Treatment: He was vigorously reassured and given some talk on sexual anatomy. No further attack occurred.
-- from Gwee Ah Leng, “Koro--a cultural disease,” In Simons, Ronald C.; and Hughes, Charles C., eds. (1985) The Culture-Bound Syndromes: folk illnesses of psychiatric and anthropological interest. (Dordrecht, The Netherlands: D. Reidel Publishing Company.) p. 156.

Well-attested individual cases of koro in China or SE Asia are relatively infrequent: Yap found 19, later researchers have compiled perhaps another 20 or 30. However, koro occurs in epidemics, in which hundreds or thousands of cases occur. Cheng (1996) reports that epidemics occur frequently in Hainan Island and Leizhou Peninsula, Guangdong Province. There was a famous epidemic in Singapore in 1967, and a more recent and puzzling one in India. Edwards claims that traditional Chinese medical specialists dismissed the epidemic in Singapore as "not really suo yang", which raises the question for the semantic hair-splitter (which most of the culture-bound syndrome specialists are) of the ontological (and emic-etic) status of epidemic koro as a CBS.

The Chinese version is situated within a larger set of concerns about the balance between male and female energies (yang and yin) within the human body. Chinese medicine sees most illnesses as symptoms of imbalance rather than as discrete entities. The term suo yang, literally translate as "shrinking penis", and represent not so much a disease as a symptom of extremely deficient yang. Thus it makes sense within the system for extreme cold (very yin) to overpower the yang in a vulnerable man and cause his penis (the symbol of his yang) to retract.

Genital retraction syndrome, usually under the name koro, is one of the most published of the culture-bound syndromes. The literature is conflicted, however. As with many of the culture-bound syndromes, some authors question the frequency of cases and accuracy of reporting, as well as the conflation of Malaysian koro with Chinese suo yang.

Much of the literature, in fact, revolves around erudite (and not-so-erudite) arguments about the derivation of the terms for GRS. Koro is a a word of probably Malaysian (Macassarese or Buginese) derivation, which may have originally meant either "shrink" or "turtle". The latter has support both from the use of "turtle" as a local slang word for penis, and from taboos associating the turtle -- known for its ability to retract its head and legs into its carapace -- with supernatural dangers to males (Edwards, 1985: 170). Another tendency of etymological discussion has been to multiply the variant spellings and local pronunciations of the Chinese terms (simplified Chinese: 缩阳; traditional Chinese: 縮陽): among others, suo1 yang2, (Mandarin), suk-yeong or suk7 joeng4 (Cantonese), siok4 iong5 (Hokkien), and shuk yang or shook yang (Shanghai) are all given.

This site was created on 21 Sep 1996. All original textual and photographic material on these pages is copyrighted 1996-2012 by Timothy M. Hall unless otherwise noted.