Skeletopic analysis of the gonadal veins in human foetuses.

During ontogenesis an imbalance is observable in the development of the skeletal and vascular systems. By means of anatomical and radiological methods the gonadal veins were studied in relation to the vertebral column in 60 human foetuses of both sexes aged from 4 to 6 months of prenatal life. In male foetuses aged 4--5 months the origin of the gonadal veins projected onto the sacral apex (r(1)=0.95, r(3)=0.85), and in 6(th) month they extended below the vertebral column (r(1')=0.80, r(3')=0.90). In female foetuses the origin of the gonadal veins in the 4(th) month projected symmetrically onto S(1) (r(5)=0.70, r(7)=0.70). In the 5(th) month of intrauterine life the origin of the left ovarian vein was found at S2 (r(7')=0.80) and the origin of the right one at S1-S2 (r(5')=0.80). In the 6th month the origin of the left ovarian vein was located at S(3) (r(7')=0.80) and the right one at S(2)-S(3) (r(5'')=0.90). The skeletopic analysis of the origin of the gonadal veins demonstrated gender (the origin was higher in females) and syntopic (the origin was higher on the right side) differences (p</=0.05). In foetuses of both sexes aged 4 months of prenatal life the termination of the left gonadal veins projected onto Th(12)-L(1) (r(4)=0.85, r(8)=0.80) and in foetuses aged 5--6 months it projected onto L(1)-L(2) (r(4')=0.90, r(8') = 0.95). In both sexes the termination of the gonadal veins on the right side projected constantly onto L(2) (r(2)=0.90, r(6)=0.95) from the 4(th) to the 6(th) month of intrauterine life. The skeletopic analysis of the termination of the gonadal veins showed syntopic dimorphism (p</=0.05) without gender differences (p>0.05). On the right side the termination of the gonadal (testicular and ovarian) veins projected constantly onto L(2). On the left side the termination of the left gonadal (testicular and ovarian) veins apparently descended by one vertebra (pseudodescensus).