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Vitamin C metabolism in pregnancy
358
AMERICAN
JOURliAL
Brieger, Hubertus: Vitamin Gy&k. 121: X0, 1040.
OF
OBSTETRICS
C Metabolism
AND
GYNECOLOGY
in Pregnancy,
Zt,schr. f. (+rlmrt?;h. II.
This report is from the department of Physiology at Restock, headed by Wachholder who has done considerable work with vitamin C. The st,udy was carried out to attempt to determine what happens to vitamin C metabolism in pregnancy under varying conditions of intake. The guinea pig, rat, and rabbit were used. Reports are given on only small numbers of animals and techniques are not described. Thr result,s, however, are of considerable interest. Wachholder and his associates have shown that in both young and old animals, a diet low in vitamin C gives rise to an inability to stabilize oxygen consumption although in older rats this may ultimately be stabilized at a level above the normal. In young growing animals developmental disturbances occur. ‘In general, similar changes occur in the rat, the guinea pig, and the rabbit. Moriquand reported that the guinea pig on a scorbutic diet remained free of evidence of vitamin C deficiency during the second half of pregnancy but showed such evideuce after delivery. The statement, is made that, the rabbit shows similar findings. Neuweiler, on the other hand, was unable to confirm this and st,ated that signs of scurvy appeared in the pregnant guinea pig just as quickly as in the nonpregnant. It is this disagreement which Brieger is attempting to settle. Brieger ‘s observations are based on animals obtaining a diet deficient in vit,amin C hut containing some. A superimposed graph of the oxygen consumption per gram minute over a period of nine days in three guinea pigs is shown. The pregnant deficient animal showed the most regular oxygen consumption at about normal level. The pregnant animal on full diet showed considerable variation about this level while gross variations appeared in the nonpregnant deficient, animal as evidence of an inability to stabilize oxygen consumption. Experiments were carried out to determine in vitro the ability of various tissues to protluce vitamin C under different conditions. In the guinea pig which was pregnant and had been on a green diet, no significant tissue synthesis could be Tissues of both pregnant and nonpregnant guinea pigs who had demonstrated. been on deficient but not vitamin C free diets showed significant increases in vitamin C content after six hours in normal saline at 37” C. The tissues from the pregnant animals showed a constantly greater increase than those of the nonpregnant. The greatest increase was found in the last part of pregnancy and here all maternal organs apparently synthesized vitamin C. The maternal portion of the guinea pig placeuta showed an increase in vitamin C after six hours. The fetus can synthesize little vitamin C. It is concluded that a protective mechanism is produced in pregnancy in these animals on varying degrees of vitamin C: dietary deficiencies. It is to be presumed that the human being acts somewhat similarly. Decrease in tissue vitamin C levels should not at once be considered to be evidence of an avitaminosis in view of the stability of the oxygen consumption in the pregnant deficient animal. Saturation deflcits’in pregnancy should not be translated at once into terms of deficient intake although this does not mean that. an increased intake during pregnancy is not desirable. On the contrary, lower levels of vit,amin C: in the fetus are demonstrated for the guinea pig when the intake is deficient. The synthesis of vitamin C can protect the mother but not t,he fetus from scurvy. As well, the deficient mother can develop scurvy quickly under these conditions after delivery. The questions posed by a study of vitamin C in many obstetric and gynecologic lrroblems are of such interest and probable importance that such information as is available should serve to stimulate work on the subjert even though, as in this report, the results do not yet approach finality. J.
During Pregnancy Gaehtgens, G. : Nutrition Rationing, Med. Klin. 36: 561, 1940. An investigation to maintain that
of during
the food gestation
in the Light
L.
MCKELVEY.
of Present
requirements of pregnant women a woman weighing 60 kg. (132
Day Food
leads Gaehtgena pounds) requires
AMERICAN
JOURliAL
Brieger, Hubertus: Vitamin Gy&k. 121: X0, 1040.
OF
OBSTETRICS
C Metabolism
AND
GYNECOLOGY
in Pregnancy,
Zt,schr. f. (+rlmrt?;h. II.
This report is from the department of Physiology at Restock, headed by Wachholder who has done considerable work with vitamin C. The st,udy was carried out to attempt to determine what happens to vitamin C metabolism in pregnancy under varying conditions of intake. The guinea pig, rat, and rabbit were used. Reports are given on only small numbers of animals and techniques are not described. Thr result,s, however, are of considerable interest. Wachholder and his associates have shown that in both young and old animals, a diet low in vitamin C gives rise to an inability to stabilize oxygen consumption although in older rats this may ultimately be stabilized at a level above the normal. In young growing animals developmental disturbances occur. ‘In general, similar changes occur in the rat, the guinea pig, and the rabbit. Moriquand reported that the guinea pig on a scorbutic diet remained free of evidence of vitamin C deficiency during the second half of pregnancy but showed such evideuce after delivery. The statement, is made that, the rabbit shows similar findings. Neuweiler, on the other hand, was unable to confirm this and st,ated that signs of scurvy appeared in the pregnant guinea pig just as quickly as in the nonpregnant. It is this disagreement which Brieger is attempting to settle. Brieger ‘s observations are based on animals obtaining a diet deficient in vit,amin C hut containing some. A superimposed graph of the oxygen consumption per gram minute over a period of nine days in three guinea pigs is shown. The pregnant deficient animal showed the most regular oxygen consumption at about normal level. The pregnant animal on full diet showed considerable variation about this level while gross variations appeared in the nonpregnant deficient, animal as evidence of an inability to stabilize oxygen consumption. Experiments were carried out to determine in vitro the ability of various tissues to protluce vitamin C under different conditions. In the guinea pig which was pregnant and had been on a green diet, no significant tissue synthesis could be Tissues of both pregnant and nonpregnant guinea pigs who had demonstrated. been on deficient but not vitamin C free diets showed significant increases in vitamin C content after six hours in normal saline at 37” C. The tissues from the pregnant animals showed a constantly greater increase than those of the nonpregnant. The greatest increase was found in the last part of pregnancy and here all maternal organs apparently synthesized vitamin C. The maternal portion of the guinea pig placeuta showed an increase in vitamin C after six hours. The fetus can synthesize little vitamin C. It is concluded that a protective mechanism is produced in pregnancy in these animals on varying degrees of vitamin C: dietary deficiencies. It is to be presumed that the human being acts somewhat similarly. Decrease in tissue vitamin C levels should not at once be considered to be evidence of an avitaminosis in view of the stability of the oxygen consumption in the pregnant deficient animal. Saturation deflcits’in pregnancy should not be translated at once into terms of deficient intake although this does not mean that. an increased intake during pregnancy is not desirable. On the contrary, lower levels of vit,amin C: in the fetus are demonstrated for the guinea pig when the intake is deficient. The synthesis of vitamin C can protect the mother but not t,he fetus from scurvy. As well, the deficient mother can develop scurvy quickly under these conditions after delivery. The questions posed by a study of vitamin C in many obstetric and gynecologic lrroblems are of such interest and probable importance that such information as is available should serve to stimulate work on the subjert even though, as in this report, the results do not yet approach finality. J.
During Pregnancy Gaehtgens, G. : Nutrition Rationing, Med. Klin. 36: 561, 1940. An investigation to maintain that
of during
the food gestation
in the Light
L.
MCKELVEY.
of Present
requirements of pregnant women a woman weighing 60 kg. (132
Day Food
leads Gaehtgena pounds) requires