Micro-albuminuria analysis and pregnancy. An approach to detect placentary insufficiency?

To assess the value of micro-albuminuria analysis (MA) in predicting clinical complications of placentary insufficiency in women with no known risk factor.

A blind prospective investigation 20-24 weeks into pregnancy in a nulliparous population with no known risk factor. A reactive strip with a positive threshold value of 10 mg/l is used to detect MA. Judgment criteria concerning the progress of pregnancy are based on blood pressure during the 8th and 9th month of pregnancy and on the 2nd day after delivery, on albuminuria analysis in the 8th and 9th month of pregnancy and by the existence of fetal hypotrophia at birth.

Some 218 patients participated in the investigation. MA was positive in 62 cases (28.4%). Of the 197 births which occurred 54 (27.4%) cases of positive MA, 34 (17.2%) cases presented positive judgment criteria indicating placentary insufficiency. The 21 others pregnancies are in course. MA sensitivity was thus 79.4% and specificity 83.4%. Negative predictive value (NPV) was 95.1% and positive predictive value (PPV) 50%.

Our test is a reliable, simple and easily reproducible indicator of micro-albuminuria. In comparison with other tests it gives a good detection rate of a risk group for complication of placentary insufficiency. NPV is excellent, virtually excluding the occurrence of excessive blood pressure or intra-uterine growth retardation. PPV is less good.