A nurse is educating a pregnant client about the endocrine changes during pregnancy.

Which hormone is responsible for inhibiting ovulation and stimulating milk production?

Increased renal blood flow is responsible for the increased urinary output during pregnancy.

This is because the renal plasma flow and glomerular filtration rate increase by 50% to 80% during pregnancy, resulting in more urine production.

Choice A is wrong because the glomerular filtration rate increases, not decreases, during pregnancy.

Choice B is wrong because the tubular reabsorption decreases, not increases, during pregnancy.

This is due to the increased levels of progesterone, which inhibit sodium reabsorption and cause diuresis.

Choice D is wrong because the increased plasma volume is a consequence, not a cause, of the increased renal blood flow.

The plasma volume expands by 30% to 50% during pregnancy to meet the increased metabolic demands of the mother and fetus.

Serum creatinine and urea are waste products of protein metabolism that are normally filtered by the kidneys and excreted in urine.

In pregnancy, the glomerular filtration rate (GFR) increases by about 50%, which means more creatinine and urea are cleared from the blood.Therefore, serum creatinine and urea levels decrease in pregnancy compared to nonpregnant women.

A. Increased serum creatinine and urea levels are wrong because they indicate impaired kidney function or dehydration, which are not normal in pregnancy.

C. Unchanged serum creatinine and urea levels are wrong because they do not reflect the increased GFR in pregnancy.

D. Increased glomerular filtration rate is correct but it is not a finding regarding serum creatinine and urea levels, which are the focus of the question.

Normal ranges for serum creatinine and urea vary depending on the laboratory and the units used, but based on a nonpregnant reference interval of 45-90 μmol/l (0.51-1.02 mg/dl) for creatinine and 2.5-6.4 mmol/l (7-18 mg/dl) for urea, a serum creatinine of >77 μmol/l (0.87 mg/dl) and a blood urea of >8.5 mmol/l (24 mg/dl) should be considered outside the normal range for pregnancy.