Related Experiment Video
Updated: May 9, 2026
08:07
Electromyometrial Imaging of Uterine Contractions in Pregnant Women
Published on: May 26, 2023
Reset osmostat in pregnancy: a case report.
Kemoy Harris1, Ravi Shankar, Karen Black
1Department of Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Hofstra North Shore-LIJ School of Medicine , Hempstead, NY , USA .
Summary
The reset osmostat syndrome, a condition of inappropriate antidiuretic hormone secretion (SIADH), can occur in pregnancy. This case highlights a non-physiologic reset osmostat caused by intracranial arteriovenous malformations and hemorrhage.
Area of Science:
- Nephrology
- Endocrinology
- Neurology
Background:
- The reset osmostat syndrome involves a downward shift in the threshold for antidiuretic hormone secretion.
- Physiologic reset osmostat is observed in normal pregnancies, lowering plasma osmolality.
- Inappropriate antidiuretic hormone secretion (SIADH) is a key feature.
Observation:
- A pregnant patient presented with a non-physiologic reset osmostat.
- This condition was suspected to be caused by large intracranial arteriovenous malformations and intraventricular hemorrhage.
- The patient exhibited mild, stable hyponatremia despite fluid intake variations.
Findings:
- The case demonstrates a non-physiologic reset osmostat in pregnancy.
- This syndrome should be considered in patients with apparent SIADH and stable mild hyponatremia.
- The underlying cause was attributed to significant intracranial vascular abnormalities.
Implications:
- Suspecting a reset osmostat is crucial for diagnosing unexplained hyponatremia in pregnant patients.
- Aggressive correction of serum sodium may not be necessary in these cases.
- Understanding this phenomenon aids in managing complex neurological and endocrine conditions during pregnancy.
Related Concept Videos
01:29Decreased Body Temperature
A decreased body temperature can occur in patients with hypothermia and frostbite. Heat loss with extended cold exposure overpowers the body's ability to create heat, resulting in hypothermia. Core temperature readings help classify hypothermia. Mild hypothermia is temperatures between 32 °C (89.6 °F) and 35°C (95 °F) and is caused by impaired thermoregulation. Moderate hypothermia is temperatures between 28 C (82.4 °F) and 32 °C (89.6 °F) caused by sustained extreme cold exposure, and severe...
01:27Assessing Body Temperature - Rectal
Rectal temperature measurement is considered the most precise method for assessing core body temperature and typically registers higher than oral temperature. For adults, the rectal thermometer should be inserted 1 to 1.5 inches into the rectum to obtain the most accurate reading.
Follow these steps for rectal temperature assessment:
Step 1: Perform hand hygiene and don clean gloves to prevent cross-infection.
Step 2: Position the patient in a side-lying position to better visualize the rectal...
Follow these steps for rectal temperature assessment:
Step 1: Perform hand hygiene and don clean gloves to prevent cross-infection.
Step 2: Position the patient in a side-lying position to better visualize the rectal...
01:40Hormonal Regulation
Hormones regulate a significant portion of digestion through activation of the neuroendocrine system. The neuroendocrine system of digestion contains many different hormones all with multiple functions that are both, directly and indirectly, involved in digestion.
01:33Hormonal Regulation
The renin-aldosterone system is an endocrine system which guides the renal absorption of water and electrolytes, thus managing blood pressure and osmoregulation. Activation of the system begins in the kidneys with a small cluster of cells adjacent to the afferent and efferent blood vessels of the renal corpuscle. As the nephrons are filtering blood, juxtaglomerular cells monitor blood pressure. If they detect a decrease in pressure, they release the hormone renin into the bloodstream.