Pregnancy in women with renal disease. Part I: general principles.

The purpose of this review is to improve the basis upon which advice on pregnancy is given to women with renal disease and to address issues of obstetric management by drawing upon the accumulated world experience. To ensure the proper rapport between the respect for patient's autonomy and the ethical principle of beneficence, the review attempts to impart up-to-date, evidence-based information on the predictable outcomes and hazards of pregnancy in women with chronic renal disease. The physiology of pregnancy from the perspective of the affected kidney will be discussed as well as the principal predictors of maternal and fetal outcomes and general recommendations of management. The available evidence supports the implication that the degree of renal function impairment is the major determinant for pregnancy outcome. In addition, the presence of hypertension further compounds the risks. On the contrary, the degree of proteinuria does not demonstrate a linear correlation with obstetric outcomes. Management and outcome of pregnancies occurring in women on dialysis and after renal transplant are also discussed. Although the outcome of pregnancies under chronic dialysis has markedly improved in the past decade, the chances of achieving a viable pregnancy are much higher after transplantation. But even in renal transplant recipients, the rate of maternal and fetal complications remains high, in addition to concerns regarding possible adverse effects of immunosuppressive drugs on the developing embryo and fetus.