Angiotensin-II-receptor inhibitors in pregnancy

Prenatal hypocalvaria after prolonged intrauterine exposure to angiotensin II receptor antagonists

We report a case of prenatal exposure to angiotensin II receptor antagonists (ARA II) from the beginning of pregnancy in a patient with a hypokinetic dilated cardiomyopathy. This case report emphasizes the fetal renal impact of prolonged intrauterine exposure to renin-angiotensin system (RAS) blockers, and highlights that this exposure can cause severe prenatal hypocalvaria. This delayed ossification can be reversible after birth, but the presence of anhydramnios indicates an early and irreversible block of RAS blockers in the fetus that is responsible for fetal kidney development abnormalities. This association carries a high risk of neonatal death. Prolonged exposure to ARA II or other RAS blockers remains prohibited throughout pregnancy.

Reversible Fetal Renal Impairment following Angiotensin Receptor Blocking Treatment during Third Trimester of Pregnancy: Case Report and Review of the Literature

Background. Late pregnancy usage of angiotensin converting enzyme inhibitors (ACE-I) and angiotensin II receptor blockers (ARB) may cause severe oligohydramnios due to fetal renal impairment. Affected neonates will often suffer from fatal, renal, and respiratory failure. Case. A 39-year-old multigravida admitted due to anhydramnios secondary to valsartan (ARB) exposure at 30 weeks' gestation. Following secession of treatment amniotic fluid volume returned to normal. Delivery was induced at 34 weeks' gestation following premature rupture of membranes and maternal fever. During the two-year follow-up, no signs of renal insufficiency were noted. Conclusions. This description of reversible fetal renal damage due to ARB intake during pregnancy is the first to show no adverse renal function in a two-year follow-up period. This case may help clinicians counsel patients with pregnancies complicated by exposure to these drugs.

A polypeptide drug carrier for maternal delivery and prevention of fetal exposure

BACKGROUND

Pregnant females are largely overlooked in drug development due to concerns for fetal health. Additionally, pregnancy is often an exclusion criterion in clinical trials, so the safety of many drugs during pregnancy is unknown.

PURPOSE

The goal of this study was to evaluate Elastin-like Polypeptide (ELP), a synthetic protein derived from human elastin, for maternally sequestered drug delivery. ELP is a versatile drug carrier with a long plasma half-life, low immunogenicity, and the ability to be fused to nearly any small molecule or protein-based therapeutic.

METHODS

We determined the pharmacokinetics, biodistribution, and fetal exposure to the ELP drug carrier using quantitative fluorescence techniques in a rat pregnancy model.

RESULTS

After either bolus IV administration or continuous infusion over five days, ELPs accumulated strongly in the kidneys, liver, and placenta, but importantly, little to no ELPs were detectable in the fetus. Within the placenta, ELPs were localized to the chorionic plate and broadly distributed within the labyrinth, but were excluded from the fetal portion of the chorionic villi.

CONCLUSION

These data indicate that ELP does not cross the placenta, and they suggest that this adaptable drug delivery system is a promising platform for prevention of fetal drug exposure.

Clonidine versus captopril for treatment of postpartum very high blood pressure: study protocol for a randomized controlled trial (CLONCAP)

BACKGROUND

The behavior of arterial blood pressure in postpartum of women with hypertension and pregnancy and the best treatment for very high blood pressure in this period still need evidence. The Cochrane systematic review assessing prevention and treatment of postpartum hypertension found only two trials (120 patients) comparing hydralazine with nifedipine and labetalol for the treatment of severe hypertension and did not find enough evidence to know how best to treat women with hypertension after birth. Although studies have demonstrated the effectiveness of treatment with captopril, side effects were reported. Because of these findings, new classes of antihypertensive drugs began to be administered as an alternative therapy. Data on the role of clonidine in this particular group of patients, its effects in the short and long term are still scarce in the literature.

OBJECTIVES

To determine the effectiveness of clonidine, compared to captopril, for the treatment of postpartum very high blood pressure in women with hypertension in pregnancy.

METHODS/DESIGN

The study is a triple blind randomized controlled trial including postpartum women with diagnosis of hypertension in pregnancy presenting very high blood pressure, and exclusion criteria will be presence of heart disease, smoking, use of illicit drugs, any contraindication to the use of captopril or clonidine and inability to receive oral medications.Eligible patients will be invited to participate and those who agree will be included in the study and receive captopril or clonidine according to a random list of numbers. The subjects will receive the study medication every 20 minutes until blood pressure is over 170 mmHg of systolic blood pressure and 110 mmHg diastolic blood pressure. A maximum of six pills a day for very high blood pressure will be administered. In case of persistent high blood pressure levels, other antihypertensive agents will be used.During the study the women will be subject to strict control of blood pressure and urine output. This proposal has already obtained approval of the local Institutional Review Board of the coordinating center (IMIP, Recife, Brazil) and of the National Council for Ethics in Research (CONEP) of the Brazilian Ministry of Health.

TRIAL REGISTRATION

Clinical Trials Register under the number NCT01761916.

Is there an embryopathy associated with first-trimester exposure to angiotensin-converting enzyme inhibitors and angiotensin receptor antagonists? A critical review of the evidence

Drugs that interfere with the renin-angiotensin system, such as angiotensin-converting enzyme inhibitors (ACEIs) and angiotensin receptor blockers (ARBs), are widely used to manage hypertension and heart failure. Adequate functioning of the RAS is essential for normal fetal kidney development. The potential for ACEIs and ARBs to impair fetal and neonatal renal function if taken after the first trimester of pregnancy has been well documented. Although these drugs were not found to be teratogenic in animals, until recently little was known about the teratogenic effects of ACEIs and ARBs in humans when exposure was limited to the first trimester of pregnancy. New evidence from epidemiologic studies indicates that there may be an elevated teratogenic risk when these drugs are taken during the first trimester of pregnancy. However, this elevated risk does not appear to be specific to ACEIs and ARBs, but is instead related to maternal factors and diseases that typically coexist with hypertension in pregnancy, such as diabetes, advanced maternal age, and obesity. Women who become pregnant while being treated with an ACEI or ARB should be advised to avoid exposure to these drugs during the second and third trimesters of pregnancy by switching to a different class of antihypertensive drugs between weeks 8 and 10 after conception.

Antihypertensive drugs in pregnancy

Blood pressure targets and medications that are safe differ in pregnant women compared with nonpregnant individuals. The principles of treatment for mild, moderate, and severe hypertension in pregnancy, chronic versus gestational versus preeclampsia, and women hypertensive at term versus remote from term are reviewed. The choice of antihypertensive drugs also is discussed; methyldopa, labetalol, and nifedipine, among others, appear safe for use in pregnancy, whereas angiotensin converting enzyme inhibitors and angiotensin receptor blockers should be avoided. The management of increased blood pressure in the postpartum period, and agents to use in lactation, are also discussed.

Chronic hypertension with related drug treatment of pregnant women and congenital abnormalities in their offspring: a population-based study

Chronic hypertension (CH) is a common chronic disease and occurs frequently in pregnant women. The teratogenic/fetotoxic effect of certain antihypertensive drugs has been shown. The objective of this study was to investigate the association between pregnant women with CH and the possible risk of congenital abnormalities (CAs) among their offspring. The prevalence of medically recorded CH in the prenatal maternity logbook was compared between 1030 pregnant women who later had offspring with CA (case group) and 1579 pregnant women with CH who later delivered newborn infants without CA (control group). Control newborn infants were matched to cases in the population-based data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities during 1980-1996. Of 23 different CA groups with informative offspring, esophageal atresia/stenosis was a greater risk in pregnant women with CH (adjusted odds ratios with 95% confidence intervals: 3.1, 1.4-6.8). In conclusion, a higher risk of esophageal atresia/stenosis was found in the offspring of pregnant women with severe CH, which could not be explained by related drug treatments. This finding requires confirmation or lack thereof by future studies.

The efficacy of antihypertensive treatment in pregnant women with chronic and gestational hypertension: a population-based study

The efficacy of antihypertensive treatment was investigated in pregnant women with chronic hypertension (CH) or gestational hypertension (GH) on the basis of the occurrence of pregnancy complications and adverse birth outcomes. Medically recorded pregnancy complications and birth outcomes of 1579 pregnant women with CH and 1098 pregnant women with GH were compared to 34,633 pregnant women without CH, GH, preeclampsia-eclampsia or any secondary hypertension who delivered newborn infants without defects in the population-based data set of the Hungarian Case-Control Surveillance System of Congenital Abnormalities, 1980-1996. Of 1579 (4.1%) pregnant women with CH, 1522 (96.4%) were treated with antihypertensive drugs. Of 1098 (2.9%) pregnant women with GH, 657 (59.8%) were treated. Pregnant women with treated CH had a higher risk of threatened abortion, preterm delivery, and placental disorders, in addition to low-birthweight newborns. However, pregnant women with untreated CH and GH had no higher risk of pregnancy complications or adverse pregnancy outcomes. Antihypertensive treatments were not able to neutralize the harm of severe CH in pregnant women, the antihypertensive treatments were not appropriate and/or effective, or related drug treatments may contribute to these adverse effects.

Angiotensin II Receptor Blockers in Pregnancy: A Case Report and Systematic Review of the Literature

OBJECTIVE

To describe the case of a woman exposed to angiotensin-II receptor blockers (ARBs) in the preconceptional period and to systematically review the literature on the safety of these drugs when used by pregnant women.

METHODS

The case was identified at the Korean Motherisk Program (Seoul). For the systematic review, we searched the PubMed for case reports, case series, and post-marketing surveys.

RESULTS

A hypertensive woman was exposed to irbesartan prior to conception. The embryo had delayed development of upper and lower extremities and decreased digital groove. A karyotype identified a 45,XO Turner syndrome. The patient had a spontaneous abortion. Including the case reported here, 64 published cases were identified in total; 57.8% had favorable and 42.2% had unfavorable outcomes. Duration of treatment during pregnancy among women who had adverse fetal outcomes was 26.3 +/- 10.5 weeks (mean +/- SD), compared with 17.3 +/- 11.6 weeks in those who had favorable outcomes (p = 0.04).

CONCLUSIONS

Exposure to ARBs for a period longer than the first trimester of pregnancy appears to be associated with a high risk for adverse fetal outcomes.

Acute myocardial infarction associated with pregnancy

Acute myocardial infarction (AMI) during pregnancy or the early post-partum period is rare but has been shown to be associated with poor maternal as well as fetal outcome. Major changes in both diagnosis and treatment of AMI in the nonpregnant patient have lead to improved outcome which may also affect pregnant patients. The purpose of this paper is to review available information related to the pathophysiology and clinical profile and provide recommendations for the diagnosis and management of AMI occuring during pregnancy and the early post-partum period.

Toxicité fœtale des antagonistes des récepteurs de l'angiotensine II. À propos d'un cas

The fetal toxicity of angiotensin-converting enzyme inhibitors (ACEI) is now well known. Sartans which are angiotensin II inhibitors, are supposed to have the same side effects on the fetus as ACEI because of their similar mechanism of action. This is supported by experimental and clinical data. Clinical presentation of fetal exposition to sartans varies from transient oligamnios to permanent renal failure, potentially complicated by Potter syndrome. According to previously reported cases, we report a case of transitory fetal oliguria secondary to the exposure to an angiotensin-II-receptor inhibitor (valsartan) between 19 and 21 weeks' gestation. We discuss the management of pregnancies exposed to angiotensin II inhibitors.

A case surviving for over a year of renal tubular dysgenesis with compound heterozygous angiotensinogen gene mutations

Renal tubular dysgenesis (RTD) is a developmental abnormality of the renal proximal tubules found in patients with Potter syndrome. We report a female newborn with RTD who has survived for more than 18 months. Infusions of fresh frozen plasma (FFP) in the early neonatal period were effective in raising and maintaining her blood pressure. Peritoneal dialysis was required until the appearance of spontaneous urination at 29 days after birth. Histopathological examinations of the kidney revealed dilated renal tubular lumina and foamy columnar epithelial cells in the renal tubules. Endocrinological studies showed a discrepancy between low plasma renin activity (<0.1 ng/ml/hr) and high active renin concentration (135,000 pg/ml), suggesting an aberration in the renin substrate, angiotensinogen. Direct sequencing analysis revealed two novel mutations in the coding region of the angiotensinogen gene (AGT): a nonsense mutation in exon 2 (c.604C > T) and a frameshift deletion at nucleotide 1290 in exon 5 (c.1290delT). The mutations were in the compound heterozygous state, because each parent had each mutation. These findings suggest that angiotensinogen deficiency is one of the causes of RTD. A treatment of the condition with FFP may help to promote long survival.

Toxicité fœtale du candesartan

We report a case of a newborn with an oligohydramnios, acute renal failure and ossification abnormalities. The role of maternal treatment of essential hypertension by angiotensin-II receptor antagonists is discussed in regard to the literature and pathophysiological data.

Effects of maternally administered drugs on the fetal and neonatal kidney

The number of pregnant women and women of childbearing age who are receiving drugs is increasing. A variety of drugs are prescribed for either complications of pregnancy or maternal diseases that existed prior to the pregnancy. Such drugs cross the placental barrier, enter the fetal circulation and potentially alter fetal development, particularly the development of the kidneys. Increased incidences of intrauterine growth retardation and adverse renal effects have been reported. The fetus and the newborn infant may thus experience renal failure, varying from transient oligohydramnios to severe neonatal renal insufficiency leading to death. Such adverse effects may particularly occur when fetuses are exposed to NSAIDs, ACE inhibitors and specific angiotensin II receptor type 1 antagonists. In addition to functional adverse effects, in utero exposure to drugs may affect renal structure itself and produce renal congenital abnormalities, including cystic dysplasia, tubular dysgenesis, ischaemic damage and a reduced nephron number. Experimental studies raise the question of potential long-term adverse effects, including renal dysfunction and arterial hypertension in adulthood. Although neonatal data for many drugs are reassuring, such findings stress the importance of long-term follow-up of infants exposed in utero to certain drugs that have been administered to the mother.

Clinical pharmacokinetics of losartan

Losartan is the first orally available angiotensin-receptor antagonist without agonist properties. Following oral administration, losartan is rapidly absorbed, reaching maximum concentrations 1-2 hours post-administration. After oral administration approximately 14% of a losartan dose is converted to the pharmacologically active E 3174 metabolite. E 3174 is 10- to 40-fold more potent than its parent compound and its estimated terminal half-life ranges from 6 to 9 hours. The pharmacokinetics of losartan and E 3174 are linear, dose-proportional and do not substantially change with repetitive administration. The recommended dosage of losartan 50 mg/day can be administered without regard to food. There are no clinically significant effects of age, sex or race on the pharmacokinetics of losartan, and no dosage adjustment is necessary in patients with mild hepatic impairment or various degrees of renal insufficiency. Losartan, or its E 3174 metabolite, is not removed during haemodialysis. The major metabolic pathway for losartan is by the cytochrome P450 (CYP) 3A4, 2C9 and 2C10 isoenzymes. Overall, losartan has a favorable drug-drug interaction profile, as evidenced by the lack of clinically relevant interactions between this drug and a range of inhibitors and stimulators of the CYP450 system. Losartan does not have a drug-drug interaction with hydrochlorothiazide, warfarin or digoxin. Losartan should be avoided in pregnancy, as is the case with all other angiotensin-receptor antagonists. When given in the second and third trimester of pregnancy, losartan is often associated with serious fetal toxicity. Losartan is a competitive antagonist that causes a parallel rightward shift of the concentration-contractile response curve to angiotensin-II, while E 3174 is a noncompetitive "insurmountable" antagonist of angiotensin-II. The maximum recommended daily dose of losartan is 100mg, which can be given as a once-daily dose or by splitting the same total daily dose into two doses. Losartan reduces blood pressure comparably to other angiotensin-receptor antagonists. Losartan has been extensively studied relative to end-organ protection, with studies having been conducted in diabetic nephropathy, heart failure, post-myocardial infarction and hypertensive patients with left ventricular hypertrophy. The results of these studies have been sufficiently positive to support a more widespread use of angiotensin-receptor antagonists in the setting of various end-organ diseases. Losartan, like other angiotensin-receptor antagonists, is devoid of significant adverse effects.

Fetopathy associated with exposure to angiotensin converting enzyme inhibitors and angiotensin receptor antagonists

The renin-angiotensin system plays an important role in the regulation of blood pressure. The use of angiotensin converting enzyme inhibitors or angiotensin receptor blockers both control hypertension by interruption of the production or action of angiotensin II, the major end-product of the renin-angiotensin system. The use of angiotensin converting enzyme inhibitors in pregnant women revealed serious and deleterious effects on fetal development including renal failure, renal dysplasia, hypotension, oligohydramnios, pulmonary hypoplasia, and hypocalvaria. The fetal effects of angiotensin converting enzyme inhibitors seem to be greatest during the 2nd and 3rd trimesters of pregnancy. The fetal effect of angiotensin converting enzyme inhibitors during the 1st trimester is controversial. These effects may represent the effect of hypoperfusion in the fetus and not a teratogenic effect. The effect of angiotensin receptor blockers is similar to converting enzyme inhibitors. Angiotensin converting enzyme inhibitors and angiotensin receptor blockers should be avoided in all pregnant women. Alternative antihypertensive medications should be considered for use in women of childbearing years.

Teratogenicity with angiotensin II receptor antagonists in pregnancy

Angiotensin converting enzyme (ACE) inhibitors and angiotensin II (AT-II)-receptor-antagonists have been demonstrated to cause fetotoxicity when administered to women during the second and third trimester of pregnancy. Although use of ACE inhibitors during the first trimester of pregnancy seems to be safe, with no associated teratogenicity, there is not sufficient information regarding the safety of first-trimester exposure to AT-II-receptor-antagonists. We report a case of exencephaly and unilateral renal agenesia in a fetus of a diabetic woman who became pregnant while taking irbesartan.

Clinical Pharmacology of Antihypertensive Therapy

Adequate control of blood pressure poses challenges for hypertensive patients and their physicians. Success rates of greater than 80% in reducing blood pressure to target values among high-risk hypertensive patients reported by several recent clinical trials argue that effective medications currently are available. Yet, only 34% of hypertensive patients in the United States are at their goal blood pressure according to the most recent national survey. Rational selection of antihypertensive drugs that target both the patient's blood pressure and comorbid conditions coupled with more frequent use of low-dose drug combinations that have additive efficacy and low adverse-effect profiles could improve significantly US blood pressure control rates and have a positive impact on hypertension-related cardiovascular and renal mortality and morbidity. This article reviews the pharmacokinetic and pharmacodynamic principles that underlie the actions of drugs in each of the classes of antihypertensive agents when used alone and in combination, provides practical pharmacologic information about the drugs most frequently prescribed for treatment of hypertension in the outpatient setting, and summarizes the current data influencing the selection of drugs that might be used most effectively in combination for the majority of hypertensive patients whose blood pressures are not controlled adequately by single-drug therapy.

Angiotensin II receptor antagonist treatment during pregnancy

Angiotensin II (A-II) is the main effector of the renin-angiotensin system. A-II functions by binding its type 1 (AT1) receptors to cause vasoconstriction and retention of sodium and fluid. Several AT1 receptor antagonists-a group of drugs collectively called "sartans"-have been marketed during the past few years for treatment of hypertension and heart failure. At least 15 case reports describe oligohydramnios, fetal growth retardation, pulmonary hypoplasia, limb contractures, and calvarial hypoplasia in various combinations in association with maternal losartan, candesartan, valsartan, or telmisartan treatment during the second or third trimester of pregnancy. Stillbirth or neonatal death is frequent in these reports, and surviving infants may exhibit renal damage. The fetal abnormalities, which are strikingly similar to those produced by maternal treatment with angiotensin-converting enzyme (ACE) inhibitors during the second and third trimesters of pregnancy, are probably related to extreme sensitivity of the fetus to the hypotensive action of these drugs. Very little information is available regarding the outcome of human pregnancies in which the mother was treated with an AT1 receptor antagonist during the first trimester, but animal studies have not demonstrated teratogenic effects after maternal treatment with large doses of AT1 receptor antagonists during organogenesis. We conclude that pharmacological suppression of the fetal renin-angiotensin system through ACE inhibition or AT1 receptor blockade seems to disrupt fetal vascular perfusion and renal function. We recommend that maternal treatment with AT1 receptor antagonists be avoided during the second and third trimesters of pregnancy and that women who become pregnant while taking one of these medications be changed to an antihypertensive drug of a different class as soon as the pregnancy is recognized.

Fetal Toxic Effects of Angiotensin II Receptor Antagonists: Case Report and Follow-Up after Birth

OBJECTIVE:

To report a child born with renal impairment following severe anhydramnios due to maternal exposure to an angiotensin II receptor type 1 (AT1) antagonist, valsartan, and hydrochlorothiazide during the first 28 weeks of pregnancy.

CASE SUMMARY:

A hypertensive woman treated with valsartan 80 mg/day, hydrochlorothiazide 12.5 mg/day, prazosin 10 mg/day, lysine acetylsalicylate 100 mg/day, and levothyroxine 250 μg/day became pregnant. At 28 weeks' gestational age, severe anhydramnios associated with high β2-microglobulin levels in the fetal blood cord was observed. Upon discontinuation of valsartan, fetal renal prognosis improved. In this case, using the Naranjo probability scale, the renal insufficiency of the child was probably related to valsartan. At the age of 2.5 years, the child presented with only mild chronic renal insufficiency. Growth parameters were within the normal range, and there was no evidence of developmental delay.

DISCUSSION:

Exposure to AT1 antagonists during the second part of pregnancy can lead to abnormalities similar to those observed after exposure to angiotensin-converting enzyme inhibitors, that is, reduced fetal kidney perfusion that may result in oligoamnios and neonatal renal insufficiency. Fourteen previous reports of maternal exposure to AT1 antagonists during this period have been published. In 6 cases, fetal or neonatal death occurred; in 2 cases, pregnancy was terminated because of complete anhydramnios or fetal abnormalities; in 1 case, renal insufficiency persisted at 8 months of age; in 2 cases, kidney function was fairly normal at birth; and in 4 cases, including the one described here, neonatal renal failure improved in the first year of life.

CONCLUSIONS:

AT1 antagonists should be avoided throughout pregnancy. If these agents are prescribed accidentally to a pregnant woman, monitoring of amniotic fluid volume and β2-microglobulin fetal blood levels after discontinuation of the AT1 antagonist can provide critical data for advising parents on pregnancy and fetal outcome.

Angiotensin-converting enzyme inhibitors side effects--physiologic and non-physiologic considerations

Angiotensin-converting enzyme (ACE) inhibitors are increasingly recognized as having an important role in the treatment of hypertension and/or end-organ disease. The sheer number of ACE inhibitors in the United States--now numbering 10 different chemical entities--has created a sense of comfort with these compounds, which is particularly evident when these compounds are used in the patient with essential hypertension; conversely, when comorbid conditions are present in the ACE inhibitor-treated patient, circumstances change and physician vigilance becomes more of a necessity. ACE inhibitor therapy in patients with either cardiac and/or renal disease is as much an art as it is a science, and even in the most skilled hands can prove a challenging undertaking. This review discusses the physiologic and non-physiologic basis for side effects with ACE inhibition.

Cardiovascular Pharmacotherapeutic Considerations During Pregnancy and Lactation

Table 2 summarizes the recommendations regarding the use of cardiovascular drugs during pregnancy and lactation.

Fetal toxicity of valsartan and possible reversible adverse side effects

BACKGROUND

Published cases suggest that the use of angiotensin II receptor antagonists is fetotoxic during the third trimester, but not in early pregnancy.

CASE

We report a case in which the adverse fetal effect of angiotensin II receptor antagonist treatment was reversed. A woman with chronic hypertension was treated with valsartan until gestation week (GW) 20, when a complete anhydramnios was observed. Six days after interruption of the treatment, amniotic fluid reappeared. It reached a normal level at GW 23.5. The plasmatic creatinine level and the renal ultrasound examination were within normal limits at the six-month follow-up.

CONCLUSIONS

Whereas angiotensin-II-receptor antagonist generates a severe renal toxicity, this case suggests that, at least in the first half of pregnancy, these effects can be reversed.

Losartan induced fetal toxicity

Losartan is a specific angiotensin II receptor antagonist. Although the teratogenic effects of angiotensin converting enzyme (ACE) inhibitors are well documented there are limited reports of losartan induced fetal toxicity. The authors report a case of incomplete ossification of skull bones, transient oliguria and feed intolerance in a newborn following in-utero exposure to losartan.

Angiotensin II-receptor-antagonists: further evidence of fetotoxicity but not teratogenicity

BACKGROUND

Like angiotensin converting enzyme (ACE) inhibitors angiotensin II (AT II)-receptor-antagonists may cause persistent or even lethal fetotoxic defects when used during the late second or third trimester. There are insufficient data on first-trimester exposure to these substances in terms of teratogenicity. The two databases of the Berlin Teratology Information Service (TIS) were evaluated for pregnancy outcome following exposure to AT II-receptor-antagonists. One database covers case reports on newborns with congenital abnormalities identified after birth, in which drug-effect associations can be evaluated retrospectively. The other enrolls women prospectively according to exposure to particular drugs during pregnancy, with follow-up of pregnancy outcome.

CASES

Five cases (four retrospective and one prospective) involving late-pregnancy use of AT II-receptor-antagonists were recently reported to us, each of which included one or more of the following abnormalities: oligohydramnios/anhydramnios, anuria, hypoplastic skull bones, limb contractions, lung hypoplasia, and neonatal death. Among 37 prospectively enrolled first-trimester-exposed pregnancies there were 30 live births including one with a major malformation (cleft palate). One pregnancy was electively terminated after exencephaly had been diagnosed.

CONCLUSIONS

AT II-receptor-antagonists may induce fetotoxic effects when used in the second and third trimesters. The available data on first-trimester use do not strongly support a teratogenic potential. AT II-receptor-antagonists should not be used by pregnant women. In case of inadvertent exposure, therapy should be changed to the known antihypertensives of choice (e.g., metoprolol, methyldopa, and hydralazine) and fetotoxic effects should be ruled out by ultrasound. Treatment with AT II-receptor-antagonists during early pregnancy is not in itself an indication for termination of a wanted pregnancy.

The effect of antihypertensive drugs on the fetus

A critical review of the literature on the effects of antihypertensive drugs on the fetus in pregnant women is presented. The survey covers the alpha-adrenergic receptor agonists, beta-blockers including topical eye medications, alpha-beta blockers, calcium antagonists, diuretics, and angiotensin-converting enzyme (ACE) inhibitors. The lack of data on angiotensin II receptor blockers is noted although effects are considered to be similar to those reported with ACE inhibitors and therefore to be avoided. Analysis of the literature underscores that some antihypertensive drugs can be used safely at certain stages of pregnancy, while others are suspect and to be avoided at all costs. The lack of placebo-controlled studies on the treatment of severe hypertension in pregnancy due to ethical considerations is discussed against the background of the pressing need to treat these women despite the possible deleterious effects of antihypertensive drugs.