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The influence of paternal age on down syndrome

Fisch, Harry; Hyun, Grace; Golden, Robert; Hensle, Terry W; Olsson, Carl A; Liberson, Gary L
PURPOSE: Children born to older parents are at greater risk for genetic abnormalities, such as Down syndrome. The influence of maternal age on Down syndrome is well established but little is known about the genetic consequences of advanced paternal age. MATERIALS AND METHODS: Data on the incidence of Down syndrome from 1983 to 1997 (3,419 cases) were obtained from the New York State Department of Health congenital malformations registry. Parental age was modeled as individual age groups and by a single linear covariate (drift model). The log linear chi-square test and a test of significance of different explanatory variables were used to evaluate these models to determine significance. We compared actual Down syndrome rates by maternal age with the estimated rate corrected for paternal age. RESULTS: From 1983 to 1997 a dramatic increase in the number of infants born to parents 35 years or older was observed. During the 15-year study period there was an increase of 111% and 60% in the number of mothers and fathers 35 years old or older, respectively. There was no parental age influence on Down syndrome until age 35 years and older. A paternal age effect was seen in association with a maternal age of 35 years and older, and it was most pronounced when maternal age was 40 years and older (p = 0.0004). In this later maternal age group the paternal contribution to Down syndrome was 50%. CONCLUSIONS: Advanced paternal age combined with maternal age significantly influences the incidence of Down syndrome. This effect may represent a paradigm for other genetic abnormalities in children of older fathers.
PMID: 12771769
ISSN: 0022-5347
CID: 2699712

AIDS and the urologist

Hyun, Grace; Lowe, Franklin C
The management of HIV infection has dramatically altered the natural history of the disease. Prevention of opportunistic infections and the development of HAART regimens altered the manifestations and conditions that urologists are being asked to evaluate and manage in this patient population.
PMID: 12580562
ISSN: 0094-0143
CID: 2699722

Testicular growth and gonadotrophin response associated with varicocele repair in adolescent males

Fisch, H; Hyun, G; Hensle, T W
OBJECTIVE:To measure testicular volume and the gonadotrophin response to gonadotrophin-releasing hormone (GnRH) stimulation in adolescents undergoing left varicocelectomy. PATIENTS AND METHODS/METHODS:Thirteen adolescents undergoing varicocelectomy had their testicular volume and endocrine function evaluated before and after surgery. RESULTS:The initial left testicular volume was consistently smaller than the right but after surgery both increased. Baseline follicle-stimulating hormone (FSH) levels and the FSH response to GnRH stimulation increased after surgery. There were no differences in luteinizing hormone and testosterone levels, and no changes in Tanner staging. CONCLUSIONS:Unilateral varicocelectomy with ipsilateral testicular atrophy results in bilateral testicular growth and increased FSH levels. In adolescent development, elevated FSH levels in conjunction with an increased response to the GnRH stimulation test represent a normal physiological response. The GnRH stimulation test cannot be used to determine which adolescent would benefit from surgical repair.
PMID: 12614255
ISSN: 1464-4096
CID: 3888122

Parameatal repair: The modern MAGPI [Meeting Abstract]

Austin, JC; Clement, MR; Hyun, G; Snyder, HM
ISI:000184566700366
ISSN: 0022-5347
CID: 2699762

Maternal age as a risk factor for hypospadias

Fisch, H; Golden, R J; Libersen, G L; Hyun, G S; Madsen, P; New, M I; Hensle, T W
PURPOSE: Hypospadias incidence rates have been widely reported to be increasing. During the last 20 years there has been a significant increase in the number of women who delay childbearing until their mid 30s. Therefore, it was of interest to determine if increasing maternal age is an independent risk factor for hypospadias. MATERIALS AND METHODS: Data from the New York State Department of Health and California Birth Defects Monitoring Program were analyzed from 1983 to 1996 by maternal age groups of less than 20, 20 to 24, 25 to 29, 30 to 34, and 35 or greater years. A Poisson model was fitted to the data from each state using maternal age and year of birth from which relative rates were calculated. RESULTS: Our analysis revealed that advancing maternal age is significantly associated with hypospadias and is most evident for severe cases. For example, in California a 50% increase in severe cases was demonstrated for children of mothers older than 35 years compared to mothers younger than 20 years (p <0.05). CONCLUSIONS: Hypospadias is significantly associated with increasing maternal age. Women who elect to delay childbearing until their mid 30s or later should be aware that their offspring are at increased risk of hypospadias.
PMID: 11176518
ISSN: 0022-5347
CID: 2699872