Clitoral Size Research Articles

A modified approach for feminizing genitoplasty

We reported the use of the mucosal layer of preputial skin to give extra length to penile flaps on vaginal introitus and labia minora reconstruction in children with congenital adrenal hyperplasia. Since November 1999, 14 patients (average age 16 months, range 6 months-4 years) have undergone early one-stage reconstruction of external genitalia. All patients were classified according to Prader's classification (from III to V degree) with clitoral size of 3 +/- 1.5 cm. The perineal sagittal approach is followed by careful dissection and partial mobilisation of the urogenital sinus. Subcutaneous reduction clitoroplasty has been performed. The mucosal layer of the prepuce, developed as an extended flap on the end of the phallic shaft skin used for labia minora, is ideally placed for reconstruction of the vestibulae and distal vagina. The vagina was calibrated, the main vaginal calibre was 10 Hegar (range 6-14). With one exception, the urethral meatus was situated in the vestibulae and easily accessible. One distal vaginal stenosis was observed in a case with high confluence. No urinary incontinence was noted. The appearance of external genitalia was very satisfactory. The described genitoplasty provides a good cosmetic appearance. As most of our patients have not yet reached the age of sexual activity and child bearing, the functional results of this operation will need longer-term evaluation.

Clitoral and penile size variability are not significantly different: lack of evidence for the byproduct theory of the female orgasm

The evolutionary significance of the female orgasm is unclear. Adaptationist accounts seek to ascribe a positive fitness benefit to females that achieve orgasm during vaginal intercourse, spawning theories that propose the female orgasm is an adaptation to bipedalism, communal life, pair-bond formation, insemination efficiency, and mate quality assessment, among others (reviewed in Lloyd 2005). Structuralist accounts explain female orgasm as a byproduct of the evolutionary, developmental, and physiological processes that generate the male orgasm (Lloyd 2005). Thus, the byproduct hypothesis asserts that the female orgasm results from shared evolutionary and developmental processes with males and is not the result of direct selection on the trait in females. The primary evidence cited in favor of the byproduct hypothesis is the high variability in womens’ ability to achieve orgasm during vaginal intercourse compared with the near certainty of male orgasm (Lloyd 2005). A prediction of this hypothesis is that a lack of selection on female orgasm releases the genital structures responsible for triggering orgasm in women (the clitoris) from selection, leading to greater phenotypic variation than for structures under stronger selection pressure for achieving an orgasm (i.e., the penis) (Wallen and Lloyd 2008). Wallen and Lloyd (2008) recently used this expectation to examine the variability in clitoral and penile lengths for evidence of differential selection pressure. Comparing the coefficient of variation in length between the clitoris and penis from large datasets (Table 1), Wallen and Lloyd (2008) found that clitoral length was significantly more variable than penile length (P50.002). These authors concluded, ‘‘given the close connection between the clitoral structures and womens’ orgasms, this marked variability in clitoral [length, compared with variability in penile length,] suggests little or no selective pressure on clitoral structures’’ (Wallen and Lloyd 2008). However, this conclusion rests on two important assumptions: (1) clitoral length is directly related to a womens’ ability to achieve orgasm, and (2) length is the best metric for the size of the penis and clitoris. Available data refute the former assumption, while the latter is clearly a one-dimensional view of size that may not be an accurate measure of ‘‘size.’’ A more realistic metric for size should include a description of both length and width, such as volume. Therefore, I performed the same analysis as Wallen and Lloyd (2008), but used volume measures instead of length. Unlike the results reported by Wallen and Lloyd (2008) for length data, clitoral volume was not significantly different from penile volume (1.39-fold difference, P50.17; Table 1). Following the rationale of Wallen and Lloyd (2008), volume data suggest that the size of the clitoris and penis are under similar selection pressures, in contrast to their conclusion for length data. This result is particularly surprising given the strong signature of co-evolution between penile and vaginal length reported by Wallen and Lloyd (2008), which suggests that clitoral size (as measured by volume) is under particularly strong stabilizing selection despite variability in length among women. More generally, the primary argument used to support the byproduct hypothesis for the origin of the female orgasm is its uncertain occurrence during sex, which is taken as evidence for reduced or absent stabilizing selection on female orgasm. Thus, Wallen and Lloyd (2008) assume that the clitoris, as the structure primarily responsible for generating the orgasm (Narjani 1924; Masters and Johnson 1966), must also be free from stabilizing selection and this will be reflected in variation in its size. This relationship is essential for their conclusions, however, there is no relationship between clitoral size and ability to achieve orgasm (Masters and Johnson 1966). For that matter, it seems unlikely that penis size is directly related to a male’s ability to reach orgasm during sex. Indeed, the ape penis is much smaller than the human penis with the average chimpanzee’s penis approximately 14-cm long, and the average gorilla and orangutan penis only approximately 3-cm long (Diamond 1992). Yet I doubt proponents of the byproduct hypothesis would conclude that males of these species experience orgasm during intercourse less frequently than human males. Attempts to explain the female orgasm have provoked a growing and sometimes heated debate (Barash 2005; Judson 2005; Zuk 2006; see Amundson 2007 for a thoughtful review). Yet, empirical data to test hypotheses, both functional and EVOLUTION & DEVELOPMENT 10:4, 396 –397 (2008)

Transitional cell carcinoma presenting as clitoral priapism

Background. Clitoral priapism is an uncommon cause of clitoromegaly. It should be suspected in the absence of hirsuitism and the presence of clitoral engorgement, pain, and local irritation. Case. A 48-year-old female had a straight catheterization of her bladder for a history of frequent urinary tract infections. She was noted to have a clitoral size of 5 × 2.5 cm along with the classic findings of priapism. She had an 8 × 10 cm pelvic mass that was biopsied and revealed transitional cell carcinoma with papillary squamous component. Conclusion. Clitoral priapism presents with clitoral engorgement in the absence of sexual stimulation. The most common etiologies include medications, pelvic tumors, blood dyscrasias, or retroperitoneal fibrosis. A thorough investigation is warranted to identify potential pelvic venous or lymphatic obstruction.

Female genitalia: dynamic MR imaging with use of MS-325 initial experiences evaluating female sexual response.

To determine whether magnetic resonance (MR) imaging with MS-325, a recently developed blood pool contrast agent, can depict sexual arousal response in healthy women. Serial MR imaging of the external genitalia was performed in 12 healthy sexually functional women before and after administration of MS-325. MR images were obtained every 3 minutes during a 45-minute examination. During the examination, the subjects viewed neutral and erotic video material while they were in the magnet bore. MR image analysis at each interval consisted of vaginal wall, vaginal mucosa, and clitoris assessments; femoral vein signal intensity measurements; relative regional blood volume (rRBV) calculations; and clitoral volume measurements. Statistical analysis of the results was performed with a t test. On subjective questionnaires, all subjects in the test group reported being sexually aroused. MS-325-enhanced MR images showed strong contrast enhancement of the external genitalia. The rRBV in the glans clitoris of seven of 10 subjects and in the clitoral body of eight of these subjects increased significantly (P <.05) during erotic visual stimulation. All 10 subjects had a significant (P <.05) increase in clitoral size. There were no significant differences in any measures between the pre- and postmenopausal study groups. The sexual arousal response in healthy women can be monitored at serial MR imaging with MS-325. This examination holds promise for future studies of sexual arousal dysfunction in women.

The Clitoral Size of the Korean Female Newborn

Background: To determine mean clitoral and glans size of Korean female newborn. Materials and Methods: The size of glans and clitoris of 68 Korean female newborns born at Yeungnam University Medical Center were measured from May in 1999 to August in 1999. Results: The mean size of the 68 newborns were mm in glans length, mm in glans width and mm in clitoral length. In the premature infants the mean clitoral size was mm in glans length, mm in glans width and mm in clitoral length. In the full term infants mm in glans length, mm in glans width and mm in clitoral length. In low birth weight infants clitoral size was measured mm in glans length, mm in glans width and mm in clitoral length. In normal birth weight infants mm in glans length, mm in glans width and mm in clitoral length. In high birth weight infants mm in glans length, mm in glans width and mm in clitoral length. Conclusion: There was no significant correlation between gestational age and clitoral size or glans size, but significant negative correlation was found between birth weight and clitoral size or glans size.

P52Ultrasonographic diagnosis of an approach to a case with intrauterine clitoromegaly

IntroductionAdrenal androgens are one of the important determinants of sexual differentiation in fetal period. Increased circulating levels of adrenal androgens as seen in congenital adrenal hyperplasia, interact with genital skin androgen receptors and induce clitoral enlargement, fusion of labial folds and cause migration of the urethral‐vaginal perineal orifice resulting in ambiguous genitalia. We are reporting a female newborn with clitoromegaly from a nulliparous mother at term pregnancy.Case reportThe mother was followed up from 22 weeks of gestation with no signs of hyperandrogenism. Because of late application for antenatal follow up and since clitoromegaly was observed at 29 weeks of pregnancy, amniocentesis could not be done. During ultrasonographic evaluation at 29 weeks of gestation, clitoris with a size of 13 × 18 mm was detected and dexamethasone 1 × 0.5 mg orally was started to use. In reevaluation at 33 weeks of gestation clitoral size was measured as 4.8 × 6.8 mm and treatment was stopped. At 40 weeks of gestation a female neonate with 10–10 apgar scores, weighing 4040 g was delivered with caesarian section due to cephalopelvic disproportion. After delivery physical examination of the neonate revealed clitoral measurements consistent with clitoromegaly. Hyperandrogenic state of the case persists and evaluation of the newborn is going on in Pediatrics Clinic.DiscussionAlthough adrenal androgen secretion starts at 6–8 weeks of gestation and dexamethasone therapy was shown to be effective in regression of virilization if it was used as early as 6–8 weeks of gestation, our case was diagnosed later in the course of pregnancy. But when similar regimen was applied similar result was obtained. So we propose that patients with intrauterine virilization signs like clitoromegaly and ones with risk of congenital adrenal hyperplasia should take glucocorticoid therapy whenever it is determined in order to ameliorate genital ambiguity in female fetuses.

RENIN ANGIOTENSIN SYSTEM OF RABBIT CLITORAL CAVERNOSUM: INTERACTION WITH NITRIC OXIDE

Angiotensin (ANG) II has been known to be a potent modulator for the maintenance of smooth muscle tone of the penile cavernosum. However, its role in clitoral cavernosum is unknown. The clitoris is the homologue of the penis arising from the embryological genital tubercle. We investigated the presence of ANG II receptors, the function of ANG II, and its interaction with nitric oxide (NO) in rabbit clitoral cavernosum. The isometric tension was measured in the strips of clitoral cavernosum. Reverse transcriptase polymerase chain reaction (RT-PCR) was used to evaluate expression of AT1a and AT1b ANG II receptor subtype mRNAs. In vitro autoradiography was used to localize ANG II receptors in the clitoral cavernosum. The clitoral cavernosum was contracted dose-dependently by the addition of ANG II. Dup 753 (ANG II type 1 receptor antagonist) inhibited significantly ANG II induced contraction. PD 123,319 (ANG II type 2 receptor antagonist) did not affect the ANG II response. Pretreatment with NG-nitro-L-arginine methyl ester (NO synthase inhibitor) accentuated contractions induced by ANG II. Specific binding sites for 125I-ANG II were found in the clitoral cavernosum. The dissociation constant (Kd) was 0.58 + or - 0.05 nM. Specific binding of 125I-ANG II was displaced by Dup 753 (10-5 M) but not by PD 123,319 (10-5 M). The inhibitory constant (Ki) for Dup 753 was 23. 4 + or - 9.73 nM and mRNAs for AT1a and AT1b receptor subtypes were detected by RT-PCR. The present study shows that ANG II is involved in the regulation of clitoral cavernosum smooth muscle tone via ANG II receptor subtype AT1, and that ANG II has cross-talk with NO.

Morphology and chemistry of brown rat,Rattus norvegicus, preputial and clitoral glands

In contrast to previous results from laboratory rats, when sexual dimorphism occurred, clitoral glands from wild female rats were heavier and accounted for a greater proportion of body mass than preputial glands from wild males. Gland length and weight increased with body weight, but gland weight as a proportion of body weight did not. Preputial and clitoral glands showed seasonal differences in size: at one site glands were smaller in December than in April. Maturity, estrus, and pregnancy had no significant effect on clitoral gland size, but immature males had proportionally smaller preputial glands than mature males, and the absolute gland weight, but not gland weight as a proportion of body weight, increased with testes weight. There were no differences between the sexes in lipid production, which increased with preputial or clitoral gland weight. An homologous series of aliphatic acids and their methyl and ethyl esters, plus squalene, cholesterol and lanosterol, was revealed by GC-MS study of the trimethyl silyl derivatized lipid extract. Males and females could be distinguished by principal component analysis of chromatogram peaks.

The clitoral index: A determination of clitoral size in normal girls and in girls with abnormal sexual development

Clitoral measurements were obtained in normal children; small increases in clitoral dimensions were associated with growth and puberty. Patients with androgen excess had major increases in clitoral size, clearly different from normal values.

Female gender reconstruction surgery for ambiguous genitalia in children and adolescents

This review summarizes the principles of diagnosis in patients with ambiguous genitalia and surgical reconstruction for a female gender assignment. Common goals of corrective surgery are to reduce clitoral size, to create or reshape labia majora, to exteriorize or create a vagina, and to remove potentially malignant gonads. A one-stage clitorovaginoplasty was performed on four children with congenital adrenal hyperplasia (Passerini-Glazel et al., J Urol 1989, 142:565-568). The technique preserved the clitoral glans, used the skin of the urogenital sinus to line the introitus and form the distal vagina, and reshaped the labioscrotum. Early follow-up found minimal vaginal stenosis. A postpubertal vaginoplasty for undermasculinized genetic males or for patients with a flat perineum is described. All 15 patients had functional success, and 93% had anatomic success (Rock and Jones, Am J Obstet Gynecol 1989, 160:845-853). Early gender assignment helps stabilize gender identity, and neonatal reconstructive surgery of the external genitalia appears to be safe. Neovaginal construction is often performed postpubertally but should be individualized to the anomaly and the patient.

Clitoral length assessment in newborn infants of 30 to 41 weeks gestational age

Clitoromegaly in the neonatal period is an important morphological sign. There are only few reports establishing an objective assessment of clitoral size. The present study establishes normal standards for clitoral length in healthy premature and full-term infants. The data are expressed at the same time in relation to both gestational age and birth weight, two variables which are strictly intercorrelated. Appropriate curves, which permit an easy and rapid objective determination of clitoral size, are presented.

Clitoral size in full-term infants.

We have provided standards for clitoral length and width. These measurements are simple, reliable, and reproducible and should be included as part of the newborn physical examination.

172 COMBINATION THERAPY IN AN ADOLESCENT WITH POLYCYSTIC OVARIES, HIRSUTISM, TYPE A INSULIN RESISTANCE, AND ACANTHOSIS NIGRICANS

A 13½ year old female presented with primary amenorrhea, weight gain and hirsutism. Examination revealed a mildly obese adolescent with a deep voice, facial and truncal hirsutism, and acanthosis nigricans in axillae and popliteal fossae. Sexual development was Tanner stage V and clitoral size 8×15 mm. The left ovary was enlarged to palpation.Laboratory evaluation revealed a bone age of 15 years, elevation of serum testosterone and androstenedione and decrease of sex hormone binding globulin (SHBG) (Table). Pelvic ultrasound showed a cystic left ovary; laparoscopy confirmed bilateral polycystic ovaries. A glucose tolerance test showed fasting, peak and 5 hr blood glucoses of 157, 305 and 242 mg/dl, respectively, with insulin levels ranging from 144 uU/ml fasting to > 400uU/ml.The patient was placed on a combination of mestranol 50ug + norethindrone 1 mg daily and spironolactone 25 mg bid. Elevated androgen levels returned to normal and SHBG returned to near normal by 6 months of therapy and remained normal at 2 years. Facial hirsutism improved dramatically in 6 months of therapy and remains under control at 2 years.

1280 THE ANOGENITAL INDEX: A WAY TO IDENTIFY ABNORMAL LABIOSCROTAL FUSION IN INFANTS?

The clinical detection of virilized genitalia can be difficult in the preterm female since clitoral size is fully developed by the 27th wk gestation while the body as a whole is not. Absence of fat in the labia majora also makes the clitoris appear more prominent. Androgen-induced labioscrotal fusion will increase the anogenital distance, but we could find no published normal values. We have made 116 measurements of the following distances: anogenital or anus to fourchette (AF); fourchette to clitoris (FC); and anus to clitoris (AC) in infants of 27-42 wk gestational age. Not surprisingly all distances showed positive and significant correlations with body surface area, weight, length and gestational age (p<0.001). The ratio of AF/FC and AF/AC follows a Gaussian distribution and does not correlate with any of the above anthropometric variables or gestational age. Mean values ±SD for all subjects measured to date are: AF/FC = 0.582±0.149; AF/AC = 0.373±0.065. An anogenital index (AF/AC) greater than 0.5 falls outside the 95% confidence limit. This suggests labioscrotal fusion and indicates a need for further evaluation. The anogenital index is not difficult to measure if proper care is taken. Since it is independent of body size and gestational age, it should be a useful tool in the diagnosis of abnormal genitalia in both premature and full term female infants. (Supported in part by GCRC grant RR00425.)

The effect of trenbolone acetate on growth rate and carcass composition of young female rabbits

ABSTRACT1. Eighteen New Zealand White × Califomian young female rabbits (does) were paired by weight and age and, at 800 g live weight, placed on a restricted intake based on the mean body weight of each pair. On attaining 1 kg one of each pair was then given 10 mg trenbolone acetate by injection on days 1, 3 and 5 of each week. This continued until the animals reached 2·3 to 2·4 kg (5 to 6 weeks).2. There were no differences in digestible or metabolizable energy intakes between treated and untreated rabbits. However, the treated animals showed small but significant increases in rates of gain for live and empty body weight compared with control does. Treated animals also had significantly more nitrogen (P &lt; 0·001) and less energy (P &lt; 0·05) per unit empty body weight than controls. Although the proportion of total nitrogen retention was 0·19 greater (P &lt; 0·001) in treated does, total energy retention was only slightly less. Treated animals had approximately 40 g (200 g/kg) less fat and 50 g more protein (N × 6·25) than control does at the end of the trial.3. Increases in liver weight and clitoral size were observed in treated animals.

The Whole Pediatrician Catalog: A Compendium of Clues to Diagnosis and Management

This volume might be better subtitled, "All You Ever Wanted to Know About Pediatrics But Were Too Busy to Look Up." The soft-cover volume includes more than 500 pages of the kind of pediatric trivia that is of no consequence until it is needed, at which time it becomes crucial. Examples of this include tables of normal values for plasma pancreatic and salivary-type amylase, normal clitoral size in the newborn, size of gas-filled bowel loops in infants, and a table of 1,000 drug names that look alike or sound alike and therefore have the potential for causing confusion in telephoned prescriptions. A table of fast foods indicates the weight and kilocalorie and sodium content of fast foods by manufacturer; a hamburger from McDonald's can be compared with one from Burger King, a serving of shrimp with batter from Long John Silver's compared with a fish sandwich with cheese from Dairy

Mounting and receptive behavior in the ovariectomized female rat: Influence of estradiol, dihydrotestosterone, and genital anesthetization

Two experiments were performed with ovariectomized female rats in an attempt to determine whether estradiol and dihydrotestosterone work synergistically in the brain to activate mounting behavior. In Expt 1, performed in Göteborg, it was found that females treated daily with 2 μg estradiol benzoate (EB) combined with 500 μg dihydrotestosterone (DHT) displayed significantly more mounts with pelvic thrusting than other females treated with the oil vehicle, 500 μg DHT, or 2 μg EB. The behavior of rats receiving EB + DHT was indistinguishable from that of yet another group of females which received 200 μg testosterone propionate (TP). In Expt 2, performed in Rotterdam, it was found that ovariectomized female rats treated with either 200 μg TP or 2 μg EB + 200 μg dihydrotestosterone propionate (DHTP) mounted significantly more than females treated with 2 μg EB. Both clitoral size and the growth of cornified papillae on the glans clitoris were stimulated by the administration of TP or EB + DHTP. However, in no group was the frequency of mounting affected by anesthetization of the clitoris and external vagina with lidocaine paste. Lordosis quotients of females treated with EB + DHTP were significantly lower than in rats receiving either EB or TP, again regardless of whether or not the genital region was anesthetized. It is concluded that the effects of DHT on estradiol-induced mounting and receptivity most likely result from the action of this androgen on the brain, and not from the stimulatory effect which DHT may exert on genital sensory receptors.