Changes in Renal Water and Electrolyte Excretion Occurring Before and After Induced Ovulation and Their Relation to Total Oestrogen and Pregnanediol Excretion

Abstract

Summary Ovulation was induced by gonadotrophin therapy in eight women with secondary amenorrhoea. During ovarian inactivity and throughout the preovulatory and luteal phases of the induced cycles continuous measurements were made of mean urine flow and the urinary excretion of total solute, sodium, potassium, urea, total oestrogens and pregnanediol. The preovulatory rise in total oestrogen excretion was associated with a reduction in sodium output whereas the excretion of greatly increased amounts of pregnanediol after ovulation was associated with an increase in sodium excretion. Maximal pregnanediol excretion tended to coincide with a second peak in total oestrogen excretion but was unaccompanied by any further rise in sodium output. Night sodium excretion was disproportionately increased after ovulation and was associated with an increment in night potassium excretion. Alterations observed in total solute excretion and urine flow were mainly determined by changes in sodium excretion.

Plasma Solute Concentrations During Gonadotrophin-Induced Ovulation

“…The decrease in plasma urea is greater in the follicular than the luteal phase and as both urinary flow and solute excretion are increased after ovulation (Parboosingh et al, 1974), it would seem that increased fluid retention may be important in determining plasma levels before ovulation.…”