Size of testes, ovaries, uterus and breast buds by ultrasound in healthy full-term neonates ages 0–3 days

Abstract

Background Hormonally-sensitive organs in the neonate can change size within days of birth as circulating maternal estrogen wanes. Although several reports document the size of these organs through infancy, few focus on the near-birth period. Clinical and research evaluation of hormonal and genitourinary disorders would benefit from reference size standards. Objective We describe the size of the uterus, ovaries, testes, and breast buds in healthy term neonates. Materials and Methods As part of the Infant Feeding and Early Development (IFED) study, we sonographically measured the largest diameter of these organs in sagittal, transverse, and anterior-posterior planes for 194 female and 204 male newborns up to 3 days old. We calculated mean, median, and percentiles for longest axis length and for volume calculated from measured diameters. We evaluated size differences by laterality, sex, and race and compared our observations to published values. Results Mean length and volume, respectively, were: uterus, 4.2 cm and 10.0 cm3; ovary, 1.0 cm and 0.2 cm3; testis, 1.1 cm and 0.3 cm3 (0.4 cm3 Lambert volume); female breast bud, 1.2 cm and 0.7 cm3; male breast bud, 1.1 cm and 0.6 cm3. Breast buds were larger in females than males. Laterality differences were typically below the precision of clinical measurement. No significant race differences were detected. Conclusion Using data from our large cohort together with published values, we provide guidelines for evaluating the size of reproductive organs within the first 3 days of life. Discrepancies between our results and published values are likely attributable to technique.

Characterization of ovarian development in girls from birth to 9 months

“…The National Institute of Environmental Health Sciences (NIEHS) Infant Feeding and Early Development (IFED) Study was an observational study conducted between August 2010 and November 2013 to assess longitudinal changes in reproductive hormone concentrations and reproductive organ volumes during infancy in relation to feeding methods, that is breast milk, cow‐milk formula, or soy formula. Detailed study methods have been described previously 15,16 . Briefly, women were recruited between their third trimester of pregnancy and up to 72 hours after the birth of their child at eight Philadelphia regional hospitals.…”

“…A subset of girls had an additional ultrasound at the 8‐week visit. Research protocol‐specific trained sonographers used both curved‐array and linear‐array transducers to image the ovaries 16 . Three to four images were obtained of each ovary's largest diameter in the sagittal, transverse, and anterior‐posterior planes.…”

Liver, Spleen, and Kidney Size in Children as Measured by Ultrasound: A Systematic Review

“…Normative liver, spleen, and kidney sizes as measured by US change with the child's age, which is expected because of the normal growth and development in a healthy child. Currently published evidence demonstrates that there is no difference in abdominal organ size between boys and girls . However, a correlation was demonstrated between the organ length and the child's weight, height, body mass index, and body surface area, in which patients with a higher weight, height, body mass index, and body surface area tended to have larger organs …”

“…In contrast to adults, for whom there are established normal ranges of organ size, organ size in children relies on growth and development . Studies exist that define the normal ranges of organ size in healthy children . For example hepatomegaly is a frequent clinical finding in children that may be caused by intrinsic liver diseases or by other diseases with liver involvement .…”

Asymmetrical size and functionality of the pampas deer (Ozotoceros bezoarticus) testes: Right testis is bigger but left testis is more efficient in spermatogenesis

“…In effect, there, the response is a more reliable and robust when the right testis remains in situ, response that is probably under neural control (Frankel, Chapman, & Cook, ). In children, the right testis is bigger than the left ones (Kaplan et al., ; Kunde, Kunze, Surov, Ruschke, & Spielmann, ). On the other hand, Costa et al.…”