Related Experiment Videos
Aldosterone is secreted intermittently during pregnancy
K J Stevens1, D B Paintin, J D Few
1St Mary's Hospital Medical School, London.
British Journal of Obstetrics and Gynaecology
|January 1, 1989
Summary
Saliva aldosterone levels fluctuate significantly throughout the day in healthy pregnancies, indicating intermittent hormone secretion. A single measurement is unreliable, but multiple samples can assess aldosterone status.
Area of Science:
- Endocrinology
- Reproductive Physiology
Background:
- Aldosterone plays a crucial role in regulating blood pressure and fluid balance.
- Pregnancy is associated with significant hormonal changes, including those affecting the renin-angiotensin-aldosterone system.
Purpose of the Study:
- To investigate the diurnal pattern and variability of salivary aldosterone concentrations in healthy pregnant women.
- To compare aldosterone levels in healthy pregnancy with those in pathological pregnancy states, such as pre-eclampsia.
Main Methods:
- Saliva samples were collected hourly from healthy pregnant women at 26 and 36 weeks gestation during normal daily activities.
- Saliva aldosterone concentrations were measured and analyzed for diurnal fluctuations and half-life.
- Aldosterone levels were also assessed in women hospitalized for pregnancy disorders and in a patient with pre-eclampsia.
Main Results:
- Healthy pregnant women exhibited considerable diurnal fluctuations in saliva aldosterone, with peak levels 2-22 times higher than the lowest.
- The estimated half-life of saliva aldosterone was 72 minutes, similar to non-pregnant individuals.
- A single saliva sample provided an unreliable estimate of aldosterone status due to significant hour-to-hour and day-to-day variations.
- A patient with pre-eclampsia showed no elevation of saliva aldosterone above non-pregnant levels.
Conclusions:
- Fluctuating salivary aldosterone levels reflect intermittent aldosterone secretion, likely due to an enhanced response of the zona glomerulosa to normal stimuli during pregnancy.
- Assessing mean diurnal aldosterone concentration using multiple saliva samples is a convenient method for evaluating aldosterone status in pregnancy.
- Salivary aldosterone measurements may help differentiate healthy pregnancy from conditions like pre-eclampsia.