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Query: UMLS:C0024530 (malaria)
 44,886 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Intrauterine growth retardation and fetal hypoxia are currently related to placental insufficiency. Fetal biometry assessed by echography is entirely adapted to follow the growth and integrity of the principal fetal organs. Hypoxia induces an hemodynamic adaptation which can be detected and quantified by Doppler. The objective of this article is to review the evolution of the fetal Doppler practice for the last 20 years and especially to show that isolated Doppler measurement and only from one site (umbilical or cerebral or aortic) have a moderate negative predictive value of fetal outcome, compared to the study of the fetal hemodynamic evolution (degradation) from several sites and during several days. We will insist on the fact that (a) umbilical Doppler only gives information on placental blood flow and this information does not reflect neither the adaptation to hypoxia nor the consequences of this adaptation, (b) cerebral Doppler accounts for the vascular response to the pO(2) reduction but it does not allow to predict the consequences of this response, (c) the simultaneous study of the placental hemodynamic time course degradation and the cerebral vascular response to hypoxia allows quantification of the cumulative deficit of fetal oxygenation during this period and evaluation the adverse consequences of a sustained flow redistribution toward the brain. Finally, if cerebral vasodilation in response to hypoxia can be considered as a physiological compensatory mechanism, it is associated after several days to the appearance of irreversible fonctional (abnormal fetal heart rate) or organic (cerebral lesions) abnormalities. Adverse effects of this process are illustrated during episodes of acute hypoxia (malaria crisis of several days) or during sustained exposure of the fetus to hypoxia (pregnancy-induced hypertension).
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PMID:[Doppler monitoring of fetal circulation from multiple arteries over several days to improve evaluation of fetal prognosis]. 1259 54

The second trimester is the safest time for travelling, because the pregnant woman feels generally most at ease and the risk of spontaneous abortion and pre-term labour is very low. Possible risks must be discussed with the obstetrician before travelling. If the pregnancy is uncomplicated most airlines allow flying up to the 36th (domestic flights) and 35th (international flights) week of gestation. Unless the fetal oxygen supply is already impaired at ground level due to an underlying disease, flying does not pose a risk of fetal hypoxia. Radiation exposure during a long distant flight is low compared to the average annual exposure dosage, but the risk of thrombosis is increased. Altitudes up to 2,500 m pose no problem. Sufficient time to acclimatize must be taken when travelling to high altitudes and exercise kept to a minimum. Scuba diving is contraindicated. Since only a few drugs are completely safe during pregnancy a thorough risk/benefit evaluation is mandatory. Treatment of infections can be considerably complicated, but any necessary treatment should not be withheld because of the fear of potential fetal injury. Good knowledge of local medical resources is essential before travelling. Several personal protective measures minimize the risk of infection: food and water precautions, protection from insect bites and avoidance of crowds, unsafe sex and, if need be, freshwater. Many vaccinations are recommended for travellers. However, live vaccines are contraindicated in pregnant women because of theoretical considerations. Exceptionally a yellow fever vaccination may be given after the first trimester. Killed, inactivated or polysaccharide vaccines can be given after the first trimester after a thorough risk/benefit evaluation. Because of the potentially devastating effect of malaria to the mother and the child, travelling to endemic malaria regions should be avoided. If the risk of infection is high chemoprophylaxis with mefloquine is indicated. In low-risk countries mefloquine, in South-East-Asia artemisinin derivatives should be given as stand-by treatment.
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PMID:[Pregnancy and traveling]. 1927 37