Effect of Physiologic Perfusion-Fixation on the Morphometrically Evaluated Dimensions of the Term Placental Cotyledon

Abstract

Objective: To estimate the in vivo dimensions of the fetal villous tree of the normal term placenta.

Methods: Dual-circuit perfusion-fixation of a cotyledon from eight normal term placentas was performed with random intra-cotyledon tissue sampling. Stereologic methods were used to derive estimates of villous (intermediate and terminal) surface area and volume, and star volume (a measure of villous volume).

Results: Villous surface area (mean 20.9 m² [standard deviation 1.8]), capillary surface area (12.8 m² [1.5]), villous volume (469 mL [40]), and capillary volume (80 mL [10]) values were all approximately 50% higher than reported previously. Star volume estimates ranged from 480 to 1350 μm³.

Conclusion: Tissue perfusion-fixation more accurately reconstructs the in vivo state, resulting in higher reference values than previously thought for the fetal villous tree dimensions. Up to one-quarter of fetoplacental blood volume is likely to be accommodated within the placenta at term.

Keywords

Placenta perfusion-fixation stereology

Get full access to this article

View all access options for this article.

References

1. Hitschold T , Weiss E , Beck T , Müntefering H , Berle P . Low target birth weight or growth retardation? Umbilical Doppler flow velocity waveforms and histometric analysis of fetoplacental vascular tree. Am J Obstet Gynecol 1993;168:1260-1264.

2. Karimu AL , Burton GJ . The effects of maternal vascular pressure on the dimensions of the placental capillaries. Br J Obstet Gynaecol 1994;101:57-63.

3. Mayhew TM , Wadrop E . Placental morphogenesis and the star volumes of villous trees and intervillous pores. Placenta 1994;15:207-217.

4. Weibel ER , Stereological methods. Practical methods for biological morphometry. Vol. 1. London: Academic Press, 1979.

5. Gundersen HJG , Bagger P , Bendtsen TF , et al. The new stereological tools: Dissector, fractionator, nucleator and point sampled intercepts and their use in pathological research and diagnosis. APMIS 1988;96:857-881.

6. Cruz-Orive LM , Weibel ER . Recent stereological methods for cell biology: A brief survey. Am J Physiol 258 (Lung Cell Molec Physiol 2) 1990;L148-L156.

7. Mayhew WTM , Joy CF , Haas JD . Structure-function correlation in the human placenta: The morphometric diffusion capacity for oxygen at full term. J Anat 1984;139-691-708.

8. Giles WB , Trudinger BJ , Baird PH . Fetal umbilical artery flow velocity waveforms and placental resistance: Pathological correlation. Br J Obstet Gynaecol, 1985;92:31-38.

9. Fok RY , Pavlova Z , Benirschke K , Paul RH , Platt LD . The correlation of arterial lesions with umbilical artery Doppler velocimetry in the placentas of small-for-dates pregnancies. Obstet Gynecol 1990;75:578-583.

10.

10. Feneley MR , Burton GJ . Villous composition and membrane thickness in the human placenta at term: A stereological study using unbiased estimators and optimal fixation techniques. Placenta 1991;12:131-142.

11.

11. Jackson MR , Walsh AJ , Morrow RJ , Mullen JBM , Lye SJ , Ritchie JWK . Reduced placental villous tree elaboration in small-for-gestational-age pregnancies: Relationship with umbilical artery Doppler waveforms. Am J Obstet Gynecol 1995;172:518-525.

12.

12. Benirschke K , Kaufmann P . Architecture of normal villous tree. In: Pathology of the human placenta. 3rd ed. New York, Heidelberg, Berlin, London, Paris, Tokyo, Hong Kong, Barcelona: Springer, 1995.

13.

13. Schneider H , Panigel M , Dancis J . Transfer across the perfused human placenta of antipyrine, sodium and leucine. Am J Obstet Gynecol 1972;114:822-828.

14.

14. Spurr AR . A low-viscosity epoxy resin embedding medium for electron microscopy. J Ultrastruct Res 1969;26:31-43.

15.

15. Baddeley AJ , Gundersen HJG , Cruz-Orive LM . Estimation of surface area from vertical sections. J Microsc 1986;142:259-276.

16.

16. Kaufmann P , Sen D , Schweikhart G . Classification of human placental villi. I. Histology. Cell Tissue Res 1979;200:409-423.

17.

17. Hansen and König cited by Kaufmann P. Entwicklung der Plazenta. In: Becker V, Schiebler TH, Kubli F, eds. Die Plazenta des Menschen. Stuttgart, New York: G. Thieme Verlag, 1981: 13-50.

18.

18. Cruz-Orive LM , Weibel ER . Sampling designs for stereology. J Microsc 1981;122:235-257.

19.

19. Gundersen HJG , Jensen EB . The efficiency of systematic sampling in stereology and its prediction. J Microsc 1987;147:229-263.

20.

20. Gundersen HJG , Jensen EB . Stereological estimation of the volume-weighted mean volume of arbitrary particles observed on random sections. J Microsc 1985;138:127-142.

21.

21. Gundersen HJG . Stereology of arbitrary particles. A review of unbiased number and size estimators and the presentation of some new ones. J Microsc 1986;143:3-45.

22.

22. Cruz-Orive LM , Hunziker EB . Stereology for anisotropic cells: Application to growth cartilage. J Microsc 1986;143:47-80.

23.

23. Bouw GM , Stolte LAM , Baak JPA , Oort J . Quantitative morphology of the placenta. I.Standardization of sampling. Europ J Obstet Gynecol Reprod Biol 1976;6:325-331.

24.

24. Hayat M . Fixation for electron microscopy. New York: Academic Press, 1981.

25.

25. Aherne W , Dunnill MS . Morphometry of the human placenta. Br Med Bull 1966;22:5-8.

26.

26. Laga EM , Driscoll SG , Munro HN . Quantitative studies of human placenta. I. Morphometry. Biol Neonate 1973;23:231-259.

27.

27. Teasdale F . Functional significance of the zonal morphologic differences in the normal human placenta. A morphometric study. Am J Obstet Gynecol 1978;130:773-781.

28.

28. Burton G , Ingram S , Palmer M . The influence of mode of fixation on morphometrical data derived from terminal villi in the human placenta at term: A comparison of immersion and perfusion fixation. Placenta 1987;8:37-51.

29.

29. Kaufmann P , Bruns U , Leiser R , Luckhardt M , Winterhager E . The fetal vascularisation of term human placental villi. II. Intermediate and terminal villi. Anat Embryol 1985;173:203-214.

30.

30. Bouw GM , Stolte LAM , Baak JPA , Oort J . Quantitative morphology of the placenta. II. The growth of the placenta and the problem of postmaturity. Eur J Obstet Gynecol Reprod Biol 1978;8:31-42.

31.

31. Bouw GM , Stolte LAM , Baak JPA , Oort J . Quantitative morphology of the placenta. III. The growth of the placenta and its relationship to birth weight. Eur J Obstet Gynecol Reprod Biol 1978;8:73-76.

32.

32. Brökelmann J. Weiers H, Bald R, Hansmann M. Die Struktur der Plazenta in Epoxid Grossschnitten und im Ultraschallbild. Teil I: Die normale Plazenta. Ultraschall Klin Prax 1988;3:70-8.

33.

33. Kingdom JCP , Ryan G , Whittle MJ et al. Atrial natriuretic peptide: a vasodilator of the fetoplacental circulation? Am Obstet Gynecol 1991;165-791-800.

34.

34. Schneider H , Stulc J , Redaelli C , Briner J . Effects of elevated umbilical venous pressure on fluid and solute transport across the isolated perfused human placental cotyledon. Trophoblast Res 1988;3:189-201.

35.

35. Boyd PA , Brown RA , Stewart WJ . Quantitative structural differences within the normal term human placenta: A pilot study. Placenta 1980;1:337-344.

36.

36. Sen D , Kaufmann P , Schweikhart G . Classification of human placental villi. II. Morphometry. Cell Tissue Res 1979;200:425-434.

37.

37. Voigt S , Kaufmann P , Schweikhart G . Zur Abgrenzung normaler, artefizieller und pathologischer Strukturen in reifen menschlichen Plazentazotten. I. Morphometrische Untersuchungen zum Einfluß des Fixationsmodus. Arch Gynäkol 1978;226:347-362.

38.

38. Leiser R , Luckhardt M , Kaufmann P , Winterhager E , Bruns U . The fetal vascularisation of term human placental villi. I. Peripheral stem villi. Anat Embryol 1985;173:71-80.

39.

39. Vesterby A , Gundersen HJG , Melsen F . Star volume of marrow space and trabeculae of the first lumbar vertebra: sampling efficiency and biological variation. Bone 1989;10:7-13.

40.

40. Karimu AL , Burton GJ . The inter-relationships between the fetal and maternal placental circulations—A new stereological approach. J Anat 1993;182:131-131.

41.

41. Kaufmann P . Development and differentiation of the human placental villous tree. Biblthca Anat 1982;22:29-39.

42.

42. Castelluci M , Scheper M , Scheffen I , Celona A , Kaufmann P . The development of the human placental villous tree. Anat Embryol 1990;181:117-128.