Diagnosis and management of diabetes insipidus during pregnancy.

OBJECTIVE

To provide an overview of diagnostic and treatment strategies in pregnant patients with diabetes insipidus (DI).

METHODS

We review the changes in osmoregulation during normal pregnancy, characterize the various types of DI that can occur during pregnancy, and discuss the recommended management.

RESULTS

The incidence of DI is 2 to 4 cases per 100,000 gestations. Central DI can precede pregnancy or manifest initially during gestation. With preexistent central DI, pregnancy usually aggravates the disorder, and the requirements for antidiuretic hormone (ADH) usually increase. Such an effect is less likely to be noted in ADH-independent nephrogenic forms of DI. Currently, the major type of DI associated with pregnancy is a transient syndrome that is resistant to arginine vasopressin (AVP) but responsive to desmopressin (dDAVP); such cases of DI are often associated with liver abnormalities or preeclampsia. This syndrome is explained by excess vasopressinase, a placental enzyme which degrades AVP but not dDAVP. A transient recurrent type of DI can occur during gestation in patients with limited ADH-secreting capacity and is responsive to both AVP and dDAVP. Latent central DI manifesting after complicated delivery and transient nephrogenic DI, resistant to both AVP and dDAVP, have also been reported.

CONCLUSION

The differential diagnosis of polyuric and polydipsic states during pregnancy is broad, and precise diagnosis may be difficult. The use of dDAVP to treat DI during gestation has proved effective and safe for both the mother and the fetus.