THE EFFECT OF SARTANS ON THE PREGNANCY

Abstract

Background. Sartans are commonly prescribed drugs for treatment of hypertension among general population. Data on their fetal toxicity are limited to small uncontrolled series and case reports; first such case was described in 2001. It is a well known that sartans therapy in the second and third trimesters of pregnancy is associated with nephrotoxic effect on fetus which results in oligohydramnios, fetal hypertension, renal insufficiency and fetal or neonatal death. Therapy with sartans is found only among pregnant women with diagnose of preexistent chronic hypertension and where sartans were prescribed as primary chosen therapy. Our aim is to describe samples of pregnant women who received sartans during their pregnancy.

Methods. We looked over labour and delivery records of all pregnant women, who delivered during the year 2002 and 2006 at Department of Obstetrics and Gynecology, University Medical Center Ljubljana. We analyzed courses of pregnancy for those women who received sartans during pregnancy.

Results. During the period we identified five hypertensive women who were exposed to sartans in pregnancy. Two of them were taking medications in the first trimester, course of their pregnancy was normal and the baby was delivered healthy and at term. Another pregnant woman who was also treated with sartans in the first trimester gave birth to a term baby with polydactyly. In our fourth case the therapy with irbesartan ceased in the second trimester of pregnancy when oligohydramnios was described. After stopping the drug, amniotic fluid volumes returned to normal. At 29 gestational weeks, a pathological cardiotocogram was noted and an emergency caesarean section was performed. The baby suffered from severe immaturity. The last case was a pregnant woman with chronic renal failure and arterial hypertension. Therapy with losartan and nifedipine was stopped at the end of second trimester. At the time oligohydramnios was also diagnosed. It persisted until spontaneous delivery at 27 gestational weeks. Aside from immaturity, the newborn suffered from transitional renal impairment.

Conclusions. All three pregnancies, where sartans were administrated during the first trimester, ended favorably. From relatively adverse reports we gather that sartan therapy during first trimester of pregnancy probably does not present a higher risk for fetal malformations. Both other pregnancies, where therapy with sartans was stopped in the second trimester were complicated by oligohydramnios. In one of the two, oligohydramnios regressed spontaneously after the therapy had been stopped. In the last case reduced amniotic fluid persisted and it resulted in reversible renal insufficiency of the newborn. A literature review of recent articles reveal the risk of fetal nephrotoxicity due to sartans administered to the mother still during second half of the pregnancy. Renal insufficiency may be reversible or it may persist after cessation of sartan therapy. Based on data available from the literature and from our own five case reports, we can conclude that women who are treated with sartan at the childbearing age should be very well informed of possible teratogenic effects of the therapy. In case of unplanned pregnancy the therapy should be stopped as soon as the pregnancy is documented. However, additional studies are needed to better define the effect of sartans on the pregnancy.