Incidence at birth and natural history of cryptorchidism: A study of 10,730 consecutive male infants

Abstract

Of the 10,730 neonates born in the period 1978-1997 and examined for cryptorchidism (C) at birth, 1387 were pre-term (gestational age <37 wk), and 9343 were full-term. At birth, a total of 737 neonates (6.9%) were cryptorchid, 487 had bilateral C and 250 unilateral C. The C rate of pre-terms was 10 times higher than that of the full-terms (30.1 and 3.4%, respectively). Comparing the two studied decades, a significant decrease of C rate was found in the second decade in full-term neonates. The rates of C at birth were significantly elevated for low birth weight, babies born from mothers with an age <20 or >35 yr, newborns from mothers with A Rh positive and B Rh positive blood group. Of the 737 cryptorchid newborns at birth, 613 (83%) were re-examined after 12 months from the expected date of delivery, and those born in the period 1988-1997 were also re-evaluated at 6 months of life. Late spontaneous descent occurred in 464 cases (75.7%), while 149 (24.3%) were still cryptorchid. The incidence of C at 12 months from the expected date of delivery, after survival curve calculation, in term and pre-term infants, was 1.53 and 7.31%, respectively, in the period 1978-1987, and 1.22 and 3.13% respectively, in the 2nd decade (1988-1997). In the groups also examined at 6 months of life, spontaneous descent occurred almost completely within the first 6 months of life in term infants, but not in pre-terms. No evidence of seasonal cyclicity was found. Medical and/or surgical treatment was generally started within 2-4 yr of age earlier in the second decade of the study. In conclusion, the main risk factor for C at birth and at 12 months of life seems to be pre-term birth and low birth weight. If this is associated itself to a higher risk of infertility too, it remains to be defined.

Age at Surgery and Outcomes of an Undescended Testis

“…The prevalence at birth, otherwise known as congenital UDT, ranges from 2% to 9%. 1 Although a large proportion of cases descend spontaneously to a normal position by 3 months of age, nearly 1% remain undescended and require surgery. 2 UDT can also develop in a previously descended testis, considered an acquired UDT, although these tend to present later in childhood and have increased prevalence in prepubertal boys.…”

Gonadal development and reproductive hormones in infant boys

“…Both at birth and at 3 months, Danish boys had a significantly higher rate of cryptorchidism than Finnish boys. The prevalence of congenital cryptorchidism in Denmark was higher, and in Finland lower, than reported from population studies of other countries (55,58,63,64). In the Danish population, a temporal increase from 1.8 in the 1960s to 8.5% in the present cohort was observed for boys born with normal birth weight (65).…”

“…Cryptorchidism is often regarded as a minor malformation, and therefore not systematically reported. In consequence, prevalence data from cohort studies tend to be higher than from registries (55)(56)(57)(58). Due to spontaneous testicular descent and changes in treatment standards, the prevalence of orchidopexy cannot be applied as a substitute for population-based data (59-61) to study geographic or temporal trends.…”

Prevalence of SRY and DAX-1 gene deletion in patients with Cryptorchidism and Hypospadias – A Pilot study in North Indian Children

“…2 However, there are still contrary reports. 3,4 On the other hand, there is a general agreement on the seasonality of cryptorchidism with spring and autumn being the seasons of significantly highest (peak in March) and lowest (trough in September) incidence, respectively. 5,6 Most researchers attribute the above phenomenon to analogous seasonal variations of sex hormones.…”