The Clinical Significance of the Basal Metabolic Rate in Pregnancy

Gordon, William John (1958) The Clinical Significance of the Basal Metabolic Rate in Pregnancy. MD thesis, University of Glasgow.

Abstract

A study was made of the basal metabolic rates of sixty normal pregnant women at various stages in pregnancy. The merits of the various methods which have been employed in measuring the basal metabolic rate have been discussed and the method used is described in detail. It was found that satisfactory results (as suggested by the quiet and regular respiratory movements) could be obtained from the third of three consecutive tests without the use of sedative drugs. The influence of the stage of pregnancy, age and parity on the basal metabolic rate was observed. It was found that there was a progressive rise in basal metabolic rate from the third to the eighth lunar month of pregnancy when a level of 40.26 Kcals./Sq./m.per hour was reached. This represents an increase of 24% over the normal non-pregnant rate. Thereafter from the eighth lunar month to delivery the rate remained at an almost constant level. The results obtained compared favourably with those of other workers although it was apparent from a study of the literature that there was a considerable variation in the results obtained by various workers. The possible reasons for the rise in basal metabolic rate associated with pregnancy were considered and the relative literature has been discussed. It is suggested that both foetal and maternal factors contribute to the increase. It is postulated that a hormonal influence, possibly arising in the placenta causes stimulation of the thyroid gland which results in an increase in the basal metabolic rate. Neither age nor parity have any significant influence on the basal metabolic rate during the reproductive years. An attempt was made to observe closely the behaviour of the basal metabolic rate prior to the onset of labour. No significant fluctuations in the rate were noted. A study of the basal metabolic rate in other than normal pregnancy was made. This included observations in multiple pregnancy, in pregnancy where intrauterine death of the foetus had occurred, in pregnancy complicated by pre-eclamptic toxaemia and cardiac disease. The relevant literature was perused and the results compared with those of other workers. The basal metabolic rate in multiple (twin) pregnancy as studied in six subjects showed a considerable increase over the rate pertaining where a single foetus existed but the increase was not proportional to the number of foetuses present. This further substantiates the suggestion that the increase in basal metabolic rate in normal pregnancy is not entirely due to foetal influence. Six subjects in whom intra---uterine death of the foetus had occurred were studied. The basal metabolic rate was found to be significantly reduced to almost pre-pregnancy levels. This suggested that the estimation of basal metabolic rate in such cases might be used as an aid to the diagnosis of intra-uterine foetal death. The influence of pre-eclamptic toxaemia on the basal metabolic rate was investigated in ten patients. It was found that in the established condition a significant rise in basal metabolic rate occurred. The results of other workers in this field have been discussed and the significance of a reduction in basal metabolic rate as a precursor of toxaemia of pregnancy, as suggested by some workers, commented upon. (Abstract shortened by ProQuest.).

• Item Type: Thesis (MD)
• Qualification Level: Doctoral
• Keywords: Medicine, Physiology, Obstetrics, Endocrinology
• Date of Award: 1958
• Depositing User: Enlighten Team
• Unique ID: glathesis:1958-79259
• Copyright: Copyright of this thesis is held by the author.
• Date Deposited: 05 Mar 2020 11:13
• Last Modified: 05 Mar 2020 11:13
• URI: https://theses.gla.ac.uk/id/eprint/79259