From http://www.ncbi.nlm.nih.gov:80/entrez/query


```````````````````````````````````````````````````````

2: Int J Gynaecol Obstet 1997 Jun;57(3):259-65

FULL-TERM BIRTH WEIGHT AND PLACENTAL MORPHOLOGY AT HIGH AND LOW ALTITUDE.

Khalid ME, Ali ME, Ali KZ.

Department of Physiology, Abha Medical School, Saudi Arabia.

OBJECTIVE: To study the association between placental morphology and
full-term birth weight at high and low altitude. SUBJECTS: Twenty normal
pregnant women living permanently at high altitude (3100 m) and 20 normal
pregnant women living permanently at low altitude (500 m) in Southern Saudi
Arabia. METHOD: For each subject in the two groups the mean hemoglobin
concentration and hematocrit values throughout pregnancy were estimated and
these were used as indices for maternal hypoxia. After delivery, the birth
weight of each fetus was determined together with the placental weight.
Placentas were then examined histologically using sections stained by
periodic acid-Schiff and hematoxylin-eosin. The mean percentages of villi
with syncytial knots, cytotrophoblastic cells and fetal capillaries were
determined. RESULTS: The mean hemoglobin concentration and hematocrit
values were significantly greater at high altitude than at low altitude (P
< 0.001 for both). The mean birth weight and placental weight were
significantly greater at low altitude compared to high altitude (P < 0.025
and 0.001, respectively). The placentas from high altitude showed
histological changes suggestive of placental hypoxia i.e. significant
increase in the incidence of syncytial knots, cytotrophoblastic cells and
fetal capillaries at high altitude compared to low altitude (P < 0.005,
0.001 and < 0.05, respectively). At both high and low altitude the
incidences of syncytial knots and cytotrophoblastic cells showed positive
and significant correlations with mean maternal hemoglobin (r = 0.5 and
0.6, P < 0.01 and < 0.001, respectively) and hematocrit (r = 0.5 and 0.6, P
< 0.01 and 0.001, respectively) during pregnancy and negative and
significant correlations with fetal birth weight (r = -0.4 and -0.6, P <
0.01 and P < 0.001, respectively). CONCLUSION: The low birth weight
observed at high altitude compared to low altitude appeared to be mainly
secondary to placental hypoxia resulting from maternal hypoxia which in
turn was caused by high altitude hypoxia.

PMID: 9215488 [PubMed - indexed for MEDLINE]



~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
"I have sworn upon the altar of God, eternal hostility against every form
of tyranny over the mind of man." --Thomas Jefferson, an early advocate of
Hyperbaric Oxygen Therapy.
----------------------------
David Freels
2948 Windfield Circle
Tucker, GA 30084-6714
USA
770/491-6776 (phone and fax)
509/275-1618 (efax, sends fax as email attachment)
mailto:[log in to unmask]