CLASSES OF HYPERTENSION IN PREGNANCY - DI AGNOSTIC POSSIBILITIES OF PREDICTION AND DIFFERENTIATION

The class of hypertensive disorders in pregnancy has decisive influenc e on maternal and fetal outcome. The diagnosis >>hypertension in pregn ancy<< requires differentiation and classification as quickly as possi ble in order to make adequate therapeutic decisions. During the last y ears obstetricians endeavoured to establish methods of prediction and early detection of hypertensive disorders in pregnancy, that will help to identify patients of risk accurately. According to the recommendat ions of the >>International Society for the Study of Hypertension in P regnancy< (>$$) over bar>ISSHP<<) of 1986 >>hypertension in pregnancy< < is now defined as diastolic blood pressure exceeding 90 mmHg on two or more occasions (greater than or equal to 4h). >>Significant protein uria<< is defined as excretion of greater than or equal to 300 mg prot ein/24 h or 2+ positive proof of protein in urine specimen (with dipst ick). The new definition and classification of hypertensive disorders in pregnancy was made only on the basis of measurable physical paramet ers as hypertension, proteinuria as well as the unmistakeable convulsi ons in eclampsia. Edema, other subjective symptoms or pathogenetic cri teria were not regarded for the ISSHP-classification anymore. I. Gesta tional hypertension and/or proteinuria: Hypertension and/or proteinuri a developing during pregnancy (after 20th week), labor or the puerperi um (within 48 h pp.). 1. Gestational hypertension (without proteinuria ). 2.Gestational proteinuria (without hypertension), 3.Gestational pro teinuric hypertension (= preeclampsia). II. Chronic hypertension and c hronic renal disease: Hypertension and/or proteinuria preexisting or d eveloping during pregnancy (until 20th week). 1. Chronic hypertension (without proteinuria). 2. Chronic renal disease (proteinuria with or w ithout hypertension). 3. Chronic hypertension with superimposed preecl ampsia (proteinuria developing for the first time after 20th week in a woman with known chronic hypertension). III. Unclassified hypertensio n and/or proteinuria IV. Eclampsia: Occurrence of generalized convulsi ons during pregnancy, labor or within 7 days after delivery. The defin ite classification or reclassification may/must be performed no sooner than during puerperium or within 40 days after delivery. According to German perinatal studies the incidence of hypertensive disorders in p regnany is noted between 5-7%, of eklampsia between 0.5-1 parts per th ousand. Methods of prediction and early detection of hypertensive diso rders: The predictive value of the >>mean arterial pressure<< during I I. trimenon (MAP II greater than or equal to 90 mmHg), of the,rollover -testa (increase of diastolic pressure of greater than or equal to 20 mmHg), of the >>angiotensin-infusion-test<< (ANG-dose <10 ng/kg BW/min ), of the >>increase of uric acid< (>$$) over bar 3.6 mg%) proved to b e not sufficiently high enough for clinical purposes due to considerab le rates of false positive results. But >>calcium/creatinin-ratio (<0. 04) in the fasting morning urine, possibly in combination with >>micro albuminuria< (>$$) over bar 11 mu g/ml) or >>serum fibronectin<<-level s (>140%) showed a high accuracy of prediction of hypertension. Differ entiation of hypertensive disorders of pregnancy: If the diagnosis of hypertension in pregnancy is made, the next diagnostic step for differ entiation is to prove or exclude a >>significant proteinuria<< (includ ing its quantification). According to the research of our group >>disc -electrophoresis<< enables to distinct gestational hypertension from p reexistent chronic renal diseases. The positive proof of a >>significa nt hypocalciuria<< identifies preeclampsia clearly. >>beta 2-microglob ulinuria<<, but less >>beta-NAG<< supports the differentiation of gest ational hypertensive disorders from chronic hypertension.