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PubMed1979

Behavioral response to vasectomy.

This article reviews the literature concerning the behavioral and psychological response of men and their wives to the vasectomy operation when used as a contraceptive technique. The data suggest that two primary changes may frequently be observed postoperatively. Individuals who have experienced anxiety in conjunction with intercourse because of a fear of contraceptive failure or pregnancy tend to report a decline in anxiety and a disinhibition of sexual arousal postoperatively. Also, test results suggest that behavoir patterns within the marital dyad are altered in some cases when the men adopt stereotyped masculine behavior, presumably to deny any suggestion that they are less masculine because of the operation. Ramifications of these findings as well as numerous other speculations, are considered, along with the suggestion that prescreening and postvasectomy counseling may help reduce negative response to the operation.

Adult↗
PubMed1998

Sonographic finding of undescended testes in fetuses at 35-40 weeks: significance and outcome.

PURPOSE: We evaluated the outcome of fetuses with prenatally diagnosed undescended testes at 35 weeks or more of gestation. METHODS: We identified the fetuses in our database in whom undescended testes were identified sonographically in the last month of pregnancy and for whom outcome information could be obtained. Associated sonographic abnormalities were tabulated from the original reports. Outcomes were obtained through reviews of the pediatric medical records and pathology reports. RESULTS: Six fetuses in 5 patients (1 had twins) were identified as having an empty scrotum at 35 weeks or later. In 3 fetuses, this finding was the only prenatal sonographic abnormality. One of these fetuses had isolated undescended testes at birth; the twins were found at birth to be females with congenital adrenal hyperplasia and severe masculinization of the genitals. The other 3 fetuses had other malformations seen prenatally, including omphalocele and macroglossia (Beckwith-Wiedemann syndrome), a left diaphragmatic hernia, and multiple congenital abnormalities. CONCLUSIONS: Although the finding of undescended testes in late gestation may be noted in an otherwise normal fetus, it may also be associated with a potential risk for perinatal problems ranging from severe multiple congenital abnormalities to incorrect sex assignment due to masculinization of female genitalia.

Cryptorchidism↗
PubMed1999

Lesbians, bisexual women, and body image: an investigation of gender roles and social group affiliation.

OBJECTIVE: This study examined the effects of considering oneself to be masculine, feminine, or androgynous in appearance, of having friends who share one's gender and sexual orientation, and of affiliating with three subcommunities within the lesbian society on various aspects of body image. METHOD: Self-report measures were obtained from 188 lesbian and bisexual females. RESULTS: Feminine women reported lower body satisfaction than did androgynous or masculine identified subjects. Those whose friends shared their sexual orientation and gender had more positive body images than those whose friends shared only gender. In contrast, community affiliation was unrelated to body satisfaction. DISCUSSION: Within-group differences among lesbians may be central to understanding body image in this group.

Adolescent↗
PubMed1999

Involvement of estrogens in the process of sex differentiation in two fish species: the rainbow trout (Oncorhynchus mykiss) and a tilapia (Oreochromis niloticus).

In order to study the physiological implication of sex steroid hormones in gonadal sex differentiation in fish, we first investigated the potential role of estrogens using two fish models: the rainbow trout (Oncorhynchus mykiss) and a tilapia species (Oreochromis niloticus). All experiments were carried out on genetically all-male (XY) and all-female (XX) populations. In vivo treatments with an aromatase inhibitor (ATD, 1,4,6- androstatriene-3-17-dione) result in 100% masculinization of an all-female population in rainbow trout (dosage 50 mg/kg of food) and 75.3% in tilapia (dosage 150 mg/kg of food). In tilapia, the effectiveness of the aromatase inhibition by ATD is demonstrated by the marked decrease of the gonadal aromatase activity in treated animals versus control. No masculinization is obtained following treatment with an estrogen receptor antagonist (tamoxifen) in both species. Aromatase and estrogen receptor gene expression was studied in rainbow trout by semi-quantitative RT-PCR in gonads sampled before, during and after sex-differentiation. Aromatase mRNA is specifically detected in female gonads, 3 weeks before the first sign of histological sex-differentiation, i.e., first female meiosis. Aromatase expression in male gonads is at least a few hundred times less than in female gonads. Estrogen receptor gene is expressed in both male and female gonads at all stages with no dimorphic expression between sexes. Specific aromatase gene expression before ovarian differentiation was also demonstrated using virtual Northern blot, with no expression detected in male differentiating gonads. From these results it can be concluded that estrogen synthesis is crucial for ovarian differentiation, and transcription of the aromatase gene can be proposed as a key step in that process in fish.

Animals↗
PubMed1979

The relationship of sex role and levels of defensiveness to self-reports of fear and anxiety.

Examined the conclusions of previous research that found that femine Ss perceive themselves as experiencing greater fear and anxiety than Ss with a masculine sex-role orientation. The current study hypothesizes that these results may be confounded by the amount of expressive defensiveness exhibited by Ss (N = 99), independent of their sex-role orientation. The results, however, indicated that feminine Ss perceived themselves as experiencing greater fear than either androgynous or masculine Ss, regardless of their level of defensiveness. Contrary to previous research, there were no significant effects of either sex-role orientation or level of defensiveness on self-reported anxiety.

Anxiety↗
PubMed1982

MMPI correlates of the BEM Sex Role Inventory and Extended Personal Attributes Questionnaire in a male psychiatric sample.

Obtained normative data and MMPI correlates of two measures of sex role orientation (Bem Sex Role Inventory and Extended Personal Attributes Questionnaire) in a sample of male psychiatric inpatients (N = 55). Means and subscale intercorrelations similar to those found in college samples were found for each sex role scale. With regard to self-reports of psychopathology, desirable masculine traits generally were related positively to adjustment, undesirable masculine and feminine traits were related negatively, and desirable feminine traits were unrelated to pathology. No consistent sex role correlates with MMPI MF were found, contrary to previous research with normal groups.

Acting Out↗
PubMed1990

Sex, sex role identification, and college students' projective drawings.

A study of 109 undergraduates found that sex and sex role identification, as assessed by the Bem Sex Role Inventory (BSRI), were related significantly to sex sequence, sexual differences, and quality of drawing on the Draw-A-Person (DAP). Specifically, males and masculine persons tended to draw males first, female and feminine persons tended to draw females first, and androgynous persons were equally likely to draw a male or a female first. The greater the sexual differentiation of the female human figure drawing, the lower the subject's degree of masculinity. The single best predictor for identifying a female subject was the quality of the female figure drawing. Results were consistent with Machover's hypothesis that drawings of the human figure reveal facets of the subject's self-image.

Adolescent↗
PubMed2004

Prostaglandins for prevention of postpartum haemorrhage.

BACKGROUND: Prostaglandins have mainly been used for postpartum haemorrhage when other measures fail. Misoprostol, a new and inexpensive prostaglandin E1 analogue, has been suggested as an alternative for routine management of the third stage of labour. OBJECTIVES: To assess the effects of prophylactic prostaglandin use in the third stage of labour. SEARCH STRATEGY: The Cochrane Pregnancy and Childbirth Group trials register (March 2003). SELECTION CRITERIA: Randomized or quasi-randomized trials comparing a prostaglandin agent with another uterotonic or no prophylactic uterotonic (nothing or placebo) as part of management of the third stage of labour. There were no language preferences. DATA COLLECTION AND ANALYSIS: Eligibility, trial quality and data extraction were done by two reviewers independently. MAIN RESULTS: Twenty-four misoprostol and eight intramuscular prostaglandin trials (34,203 participants) were included. The data comparing oral misoprostol to no uterotonics/placebo are from five trials and difficult to interpret because of the heterogeneity between trials. However, the data do not suggest a substantive reduction in the rate of postpartum haemorrhage or other measures of blood loss. Oral misoprostol 600 mcg shows clinically and statistically significantly more blood loss = 1000 ml compared with conventional injectable uterotonics (seven trials, 22,749 women, 3.6% versus 2.7%; relative risk (RR) 1.34, 95% confidence interval (CI) 1.16 to 1.55). Shivering and elevated body temperature (> 38 masculine C) are the main side-effects of misoprostol and are dose related (600 mcg versus 400 mcg: shivering - two trials, RR: 1.33; 95% CI: 1.07 to 1.64). Compared to oxytocin the RR of any shivering with 600 mcg oral misoprostol is 3.29 (seven trials, 22746 women; 19.7% versus 6.0%, 95% CI 3.03 to 3.56) and temperature greater than 38 masculine C is RR 6.78 (seven trials, 22,09 women; 6.3% versus, 95% CI 5.55 to 8.30). Injectable prostaglandins are associated with reduced mean blood loss in the third stage of labour (weighted mean difference -70 ml, 95% CI -73 to -67 ml) when compared to conventional injectable uterotonics but have more side-effects. There are scarce data from this comparison on severe postpartum haemorrhage and the use of additional uterotonics, the primary outcomes of this review. REVIEWER'S CONCLUSIONS: Neither intramuscular prostaglandins nor misoprostol are preferable to conventional injectable uterotonics as part of the active management of the third stage of labour especially for low-risk women. Future research on prostaglandin use after birth should focus on the treatment of postpartum haemorrhage rather than prevention where they seem to be more promising.

Female↗
PubMedDate not supplied

The effects of neonatal exposure to testosterone on the development of behaviour in female marmoset monkeys.

Experimental investigations of sexual differentiation in primates have been mainly confined to the rhesus monkey, a highly polygamous species with marked anatomical and behavioural sexual dimorphism. The marmoset is a monogamous monkey which shows little anatomical or behavioural sexual dimorphism, and both sexes exhibit positive feedback in response to the administration of oestradiol. This monkey has a relatively short gestation period of 144 days and usually gives birth to dizygotic twins. These share a common placental circulation and hence develop as haematopoietic chimaeras. However, a female with a male co-twin is not adversely affected as a result of this and the freemartin condition does not occur. Since the newborn male experiences raised testosterone levels soon after birth it is possible that the 'critical period' for sexual marmosets were implanted with 25 mg of testosterone for 50 days after birth. After removal of the implants their genitalia remained partly masculinized and they initiated more masculine rough-and-tumble play than their controls. After puberty they exhibited a mixture of male and female sexual behaviour when presented with unfamiliar normal males and females during 15-minute behavioural trials. Four of the implanted females have also ovulated. Neonatal administration of testosterone therefore has had an organizing effect on female behaviour. Whether the marmoset is exceptional in this respect, or whether other primates which exhibit a male neonatal testosterone surge, such as man and the rhesus monkey, also undergo some postnatal behavioural differentation, remains to be seen.

Animals↗
PubMedDate not supplied

Sex-dimorphic behaviour development in the human: prenatal hormone administration and postnatal socialization.

An interdisciplinary integrative approach must be utilized in the study of psychosexual differentiation. The approach must capitalize on data derived from non-human models, from experiments of nature, and from experiments of nurture. Studies from non-human primates strongly suggest the influence of prenatal sex hormone levels on postnatal sexually dimorphic behaviours. Starting from this basis we have studied sixty young adult men whose mothers received, during pregnancy, diethylstilboestrol, diethylstilboestrol and natural progesterone, natural progesterone, or synthetic progesterone. They have been compared with matched controls not exposed in utero to exogenous hormones. Studies of socialization patterns must document the differential developmental experiences, if any, of children with atypical and typical sex-typed behaviours. To this end, we are studying 60 boys whose behaviour before puberty was decidedly feminine, and their parents, and contrasting them with masculine boys and their parents. We are also studying 50 girls whose behaviour before puberty was 'masculine', and contrasting them with 'feminine' girls. Additionally, we are studying the sexually dimorphic behaviour of children of sexually atypical parents. The parents have either undergone sex-change surgery (male-to-female or female-to-male) or are homosexual. Data from the three studies are presented. A call is made to researchers working with non-human primates to test and extend these findings.

Child↗
PubMedDate not supplied

Attention deficit/hyperactivity disorder (ADHD) symptoms and digit ratios in a college sample.

Diagnosticians recognize three subtypes of attention deficit/hyperactivity disorder (ADHD) if there are developmentally inappropriate levels (six or more symptoms) of Hyperactive-Impulsive behavior, or Inattentive behavior, or both (Combined), respectively. ADHD may partly reflect androgen dysfunction, and an arguable proxy for prenatal androgen exposure is the 2D:4D finger ratio set at least as early as week 9 in the fetus; this is lower in men than in women. We examined the relationship between digit ratios and ADHD symptoms representing the three phenotypes: ADHD/Combined as measured by "summarized" (Rasched) scales, i.e., 1) the short version of the Wender Utah Rating Scale (WURS) and a total symptom list derived from the DSM IV, and the subdivided DSM IV into 2) ADHD/Inattentive and 3) ADHD/Hyperactive-Impulsive inventories, in a sample of European-descent college students (135 female, 52 male) not selected for ADHD. All digit ratios were calculated excluding the thumb. There were significant sex differences for the 2D:4D digit ratios of both hands (RH and LH), and between the RH 3D:4D and between the LH 2D:3D ratio. In females, the more masculine the LH 2D:4D ratio, the more the ADHD/Combined symptoms (both WURS and DSM) and the more the ADHD/Inattentive symptoms and ADHD/Hyperactive-Impulsive symptoms. More masculine ratios also correlated between the total WURS and RH 2D:3D, RH 2D:4D, and LH 2D:3D; and between the inattentive DSM symptoms and LH 2D:5D, and between the ADHD/Hyperactive and Impulsive symptoms and RH 3D:4D.

Adolescent↗
PubMedDate not supplied

Studies of human physique and sexual attractiveness: sexual preferences of men and women in China.

Men and women at Northwest University (n = 631), Xi'an, China, were asked to rate the attractiveness of male or female figures manipulated to vary somatotype, waist-to-hip ratio (WHR), secondary sexual traits, and other features. In study 1, women rated the average masculine somatotype as most attractive, followed by the mesomorphic (muscular), ectomorphic (slim), and endomorphic (heavily built) somatotypes, in descending order of preference. In study 2, the amount and distribution of masculine trunk (chest and abdominal) hair were altered progressively in a series of front-posed figures. Women rated figures with no or little trunk hair as most attractive. Study 3 assessed the attractiveness of front-posed male figures which varied only in length of their nonerect penis. Numerical ratings for this trait were low, but moderate lengthening of the penis (22% or 33% above average) resulted in a significant increase in scores for attractiveness. In study 4, Chinese men rated the attractiveness of back-posed female images varying in waist-to-hip ratio (WHR from 0.5-1.0). The 0.6 WHR figure was most preferred, followed by 0.7, while figures with higher ratios (0.9 or 1.0) were significantly less attractive. Study 5 rated the attractiveness of female skin color: men expressed a marked preference for images which were lighter in color, as compared to images of average or darker skin colors. These results, the first of their kind reported for a Chinese population, support the view that sexual selection has influenced the evolution of human physique and sexual attractiveness in men and women.

Asian People↗
PubMed1978

Metric characteristics of the canine dental complex in prenatally androgenized female rhesus monkeys (Macaca mulatta).

Permanent maxillary canine teeth (C1) are appreciably larger in males than in females in most nonhominid Anthropoidea. Mandibular canines (C1) and mandibular first premolars (P3), against which C1 are sharpened in honing behavior, reflect commensurate sexual dimorphism. These three teeth constitute the canine dental complex. The canine complex crown metrics of seven mature genetically female rhesus Macaques, androgenized by prenatal exposure to testosterone propionate, were compared with a control sample (N = 12) for evidence of masculinization. The C1 and C1 were measured for clinical crown lengths (L) and mesiodistal and buccolingual widths. The functionally significant and highly dimorphic honing dimensions (HD), which approximate the honing surfaces of P3, were noted. In t-test comparisons, the C1 L and P3 HD in androgenized monkeys were significantly larger than those of the control group (P less than 0.05). Identical results were obtained with White's nonparametric ranking technique. Standardized lateral skull radiographs showing earlier dental formative stages were available for five of the seven animals, and these were compared with radiographs of control skulls. The developing C1 were longer and wider than in the controls. This was not reflected in the crown metrics of mature animals because of marked dental attrition. We concluded that androgens can masculinize the female rhesus canine complex, if given during critical periods of prenatal development. We hypothesize that genes encoding the male canine complex are normally activated by endogenous fetal androgens during such critical periods.

Animals↗
PubMed2003

Cloning of the zebra finch androgen synthetic enzyme CYP17: a study of its neural expression throughout posthatch development.

Male zebra finches develop a robust neural song system that supports singing, but females have a minimal song circuit and do not sing. Estrogens masculinize the song circuit and are especially potent during the first 3 weeks of posthatch development. The gonads do not seem to supply the masculinizing steroids, implying that another tissue synthesizes steroids. Evidence suggests that the brain is capable of synthesizing neurosteroids, which in developing zebra finches may be required for song system differentiation. Aromatase, the enzyme that synthesizes estrogen from androgen, is equally abundant in male and female brains. To investigate further the potential for neurosteroidogenesis in the zebra finch brain, we cloned and examined the expression of 17alpha-hydroxylase/17,20 lyase (CYP17), the enzyme that synthesizes the androgenic substrate for aromatase. We used Northern blots, reverse transcription-polymerase chain reaction, and in situ hybridization to show that CYP17 is transcribed in developing and adult brains. CYP17 is transcribed at developmental stages and in brain areas potentially important to aspects of the developing song system, although no sex difference was detected in mRNA levels. Our results support the hypothesis that neurosteroids may act to influence brain organization and function in the zebra finch.

Aging↗
PubMed2001

Gonadal steroids reduce the density of axospinous synapses in the developing rat arcuate nucleus: an electron microscopy analysis.

The developing brain is exquisitely sensitive to gonadal steroid hormones, which permanently differentiate the neural substrate during a critical developmental period. One of the more striking sexual dimorphisms in the adult rat brain is synaptic patterning in the arcuate nucleus (ARC); females have twice the number of axospinous synapses as males (Matsumoto and Arai [1980] Brain Res. 190:238-242). Previously, we have demonstrated that a similar dimorphism in spine densities on ARC dendrites is present as early as early as postnatal day 2 (PN2) in Golgi-impregnated rat brains (Mong et al. [1999] J. Neurosci. 19:1464-1472). Males have 37% fewer dendritic spines than females. Moreover, these spine densities are sensitive to changes in the hormonal milieu such that males castrated on the day of birth have a significant increase in spine density, whereas females masculinized at birth by gonadal steroid exposure have a decreased dendritic spine density. One of the limitations of the Golgi technique is the inability to confirm the presence of synapses. The current study used quantitative electron microscopy and demonstrated that testosterone exposure dramatically reduced axospinous synapses in the ARC by PN 2. Males had 54% fewer and masculinized females had 77% fewer axospinous synapses than females (P < 0.05 and P < 0.01, respectively). We previously reported that gonadal steroids induce coincident changes in neuronal and astrocyte morphology in the neonatal ARC (Mong et al., 1999), and here confirm that these changes include an altered synaptic pattern that is strikingly similar to that observed in the adult (Matsumoto and Arai, 1980).

Animals↗
PubMed2005

Partial demasculinization of several brain regions in adult male (XY) rats with a dysfunctional androgen receptor gene.

The adult rat posterodorsal medial amygdala (MePD) is sexually dimorphic in regional volume and neuronal soma size, both of which are larger in males than in females. This sexual dimorphism is entirely dependent on adult circulating levels of testicular androgens, and both androgen and estrogen treatment can masculinize MePD structure. We examined male rats that are rendered androgen-insensitive by the testicular feminization mutation (tfm) of the androgen receptor (AR) gene to determine how a dysfunctional AR affects this and other brain sexual dimorphisms. In adult wild-type rats, the MePD in males had a greater regional volume, rostrocaudal extent, and soma size than in females. In genetic males, defective ARs affected some but not all of these indices: MePD volume and soma size in tfm males were intermediate between those of wild-type males and females, but the rostrocaudal extent of the MePD was unaffected by the mutation, being as great in tfm males as in wild-type males. Regional volume and soma size in the suprachiasmatic nucleus was reduced in tfm males compared with wild-type males, suggesting that AR normally affects this region in male rats. Interestingly, whereas volume of the sexually dimorphic nucleus of the preoptic area was unaffected by the tfm allele, soma size in this region was reduced in tfm males compared with wild-type males. Although estrogen receptor activation has been shown to be vital for masculinization of the rodent brain, our results indicate that ARs also contribute to this process in several brain regions.

Amygdala↗
PubMed1987

Differences in maternal behavior of rats and the sociosexual development of the offspring.

This paper describes experiments designed to investigate long-term behavioral consequences for offspring of changes in maternal behavior directed toward them as pups. Specifically, the hypothesis was considered that experimentally induced alterations in maternal behavior would result in general and wide-ranging effects on offspring development, including effects on later social and sexual behavior. The first experiment looked at the effects of changing pup odors on maternal responsiveness toward the pups, and showed that the application of perfume, particularly to the anogenital region, resulted in significant lowering of maternal anogenital licking of pups. Non-pup-directed behavior did not differ between groups. The behavior of those pups that had thus differed in infant experience was then followed in three subsequent experiments. In Experiment 2, social behavior during the juvenile period was investigated, focusing particularly on the expression of social play. The most noticeable difference to emerge in this experiment was that male pups that had been anogenitally perfumed as infants showed much higher levels of social play than male or female pups from other treatment groups. The last two experiments considered adult behavior. Experiment 3 showed that there are no lasting effects of the neonatal treatment on the attractiveness an animal has for its conspecifics. In the final experiment, "masculine" sexual behavior of males (mounts with intromission), and "feminine" sexual behavior of females (i.e., lordosis and proceptive behavior) were investigated. This confirmed previous reports by Moore (1984) (Moore, C. L. (1984). Maternal contributions to the development of masculine sexual behavior in laboratory rats. Dev. Psychobiol., 17:347-363) that those male pups that had received lower rates of anogenital licking as pups showed longer intermount intervals, when tested as adults. The results are discussed in relation to the development of sexually differentiated behavior.

Animals↗
PubMed1994

Regulatory rearrangements and smg-sensitive alleles of the C. elegans sex-determining gene tra-1.

The tra-1 gene is the terminal regulator in the sex determination pathway in C. elegans, directing all aspects of somatic sexual differentiation. Recessive loss-of-function (lf) mutations in tra-1 masculinize XX animals (normally somatically female), while dominant gain-of-function mutations feminize XO animals (normally male). Most tra-1 (lf) mutations can be fitted into a simple allelic series of somatic masculinization, but a small number of lf alleles do not fit into this series. Here we show that three of these mutations are associated with DNA rearrangements 5' to the coding region. One allele is an inversion that may be subject to a position effect. We also report the isolation of a new class of tra-1 alleles that are responsive to mutations in the smg system of RNA surveillance. We show that two of these express RNAs of aberrant size. We suggest that the smg-sensitive mutations may identify a carboxy-terminal domain required for negative regulation of tra-1 activity.

Alleles↗