• Muhammad Ashfaq
  • Muhammad Zahoor Janjua
  • Muhammad Nawaz


Back ground: Maternal smoking is one of leading causes of premature labour and low birth weight babies. Nicotine and carbon monoxide both induce degenerative changes as well as premature aging of placenta. Degenerative changes induce increased amount of collagen in chorionic villi and increased thickness of subtrophoblastic basement membrane. Premature aging is indicated by increased number of syncytial buds and higher percentage of apoptosis in smoker’s placentae. Premature aging and degenerative changes may reduce the functional component of placenta and lead to abnormal outcome of pregnancy. This study was designed to determine the effects of maternal smoking on placental morphology. Methods: Total 40 full term placentae, 20 from normal and 20 from smoker mothers were studied histologically. Full thickness pieces of each placenta from standard area were taken for paraffin embedment. Four micron thick sections were cut on rotary microtome and stained with haematoxylin and Eosin, Malloryis trichrome and hexamine silver for syncytial buds, Apoptotic cells, chorionic villous collagen and Subtrophoblastic basement membrane. Results:This study demonstrates that there is extensive aging and degenerative changes in smoker’s placentae. The aging process is shown by increased syncytial buds per unit area and high percentage of apoptosis. Degenerative changes are indicated by increased amount of collagen in chorionic villi and increased thickness of subtrophoblastic basement membrane. Conclusion: Extensive premature aging and degenerative changes in smoker’s placentae decrease the functional component of an organ, reducing its nutritive and excretory functions. This may be the cause of low birth weight babies in smokers. Extensive loss of trophoblasts by apoptosis and syncytial buds may lead to hormonal imbalance and premature labour in smokers.Keywords: Placenta, Smoking, Degeneration, Aging


Moore KL. The developing human, 3rd ed, Philadelphia; WB Saunders 1983; PP 65-6.

Guyton AC. Text book of medical physiology 8th ed, Philadelphia; WB Saunders, 1991; PP 917-9.

Katzung BG. Basic and clinical pharmacology, 7th ed., San Francisco, Appleton and Lange, 1998; PP 90-2.

Hill AB. A short text book of medical statistics, 10th ed, London; ELBS, 1977;PP 127-36.

Lehtovirta P, Fross M, Kariniemi V, Ruuramo I. Acute effects of smoking on foetal heart rate variability. Br J Obstet Gynaecology 1983; 90:3-6.

Dadak CH, Leithner CH, Sinzinger H, Silberbauer K. Diminished prostaglandin formation in umbilical arteries of babies born to women who smoke. Lancet 1981;1:94-5.

Wingerd J, Christianson R, Lovitt WV, Schoen EJ. Placental ration in white and black women. Ratio to smoking and anaemia. Am J Obstet Gynaecol 1976;124:671-90.

Smith SC, Baker PN, Symonds ME. Placental apoptosis in normal human pregnancy. Am J Obstet Gynecol 1997;177:57-65.

Majno G, Joris I. Cells, Tissues and disease, Principle of general pathology, 2nd ed, Massachusetts, Blackwell Science, 1996;PP 681-2.

Mallory FB, Parker F. Reticulum. Am J Path 1927;3:515-7.

Tenny B Jr. Study of collagen of placenta. Am J Obstet Gynecol 1934;29:819-25.

Mulcahy R, Murphy J, Martin F. Placental changes and maternal weight in smoking and non smoking mothers. Am J Obstet Gynecol 1970;106:703-4.

Tominaga T, Page EW. Accommodation of human placenta in hypoxia. Am J Obstet Gynecol 1966;94:679-91.

Bartholomew RAa, Kracke RR. Histogenesis of degenerative process in normal mature placenta. Am J Obstet Gynecol 1932;24:797-801.

Kerr JFR, Wylie AH, Cume AR. Apoptosis: a basic biological phenomenon with wide ranging implications in tissue kinetics. Br J Cancer 1972;26:239-57.

Most read articles by the same author(s)

1 2 3 > >>