Judy Arnon

Vitamin K antagonists and pregnancy outcome - A multi-centre prospective study

Vitamin K antagonists (VKA) are known to act as teratogens; however, there is still uncertainty about the relative risk for birth defects and the most sensitive period. In a multi-centre (n = 12), observational, prospective study we compared 666 pregnant women exposed to phenprocoumon (n = 280), acenocoumarol (n = 226), fluindione (n = 99), warfarin (n = 63) and phenindione (n = 2) to a non-exposed control group (n = 1,094). Data were collected by institutes collaborating in the European Network of Teratology Information Services (ENTIS) during individual risk counselling between 1988 and 2004. Main outcome measures were coumarin embryopathy and other birth defects, miscarriage rate, birth-weight, and prematurity. The rate of major birth defects after 1st trimester exposure was significantly increased (OR 3.86, 95% CI 1.86-8.00). However, there were only two coumarin embryopathies (0.6%; both phenprocoumon). Prematurity was more frequent (16.0% vs. 7.6%, OR 2.61, 95% CI 1.76-3.86), mean gestational age at delivery (37.9 vs.39.4, p<0.001), and mean birth weight of term infants (3,166 g vs. 3,411 g; p < 0.001) were lower compared to the controls. Using the methodology of survival analysis, miscarriage rate reached 42% vs. 14% (hazard ratio 3.36; 95% CI 2.28-4.93). In conclusion, use of VKA during pregnancy increases the risk of structural defects and other adverse pregnancy outcomes. The risk for coumarin embryopathy is, however, very small, in particular when therapy during the 1(st) trimester did not take place later than week 8 after the 1(st) day of the last menstrual period. Therefore, elective termination of a wanted pregnancy is not recommended if (inadvertent) exposure took place in early pregnancy. Close follow-up by the obstetrician including level II ultrasound should be recommended in any case of VKA exposure during pregnancy.

Is carbamazepine teratogenic? A prospective controlled study of 210 pregnancies

The Israeli Teratogen Information Service prospectively followed up 210 pregnancies with first trimester carbamazepine exposure. Pregnancy outcome was compared with that of two overlapping controls, matched and general (n = 629), exposed to nonteratogenic agents. Our study suggests a twofold increase in the rate of major congenital anomalies (12/160 [carbamazepine] versus 18/560 [general control]; relative risk 2.24; 95% CI 1.1–4.56) and a birth weight reduction of approximately 250 g after in utero exposure to carbamazepine.

Pregnancy outcome following in utero exposure to lithium: a prospective, comparative, observational study.

OBJECTIVE The authors conducted a prospective, comparative observational study to evaluate the risk of major anomalies following exposure to lithium during pregnancy. METHOD A total of 183 lithium-exposed pregnancies of women who contacted the Israeli Teratology Information Service were followed up (90.2% in the first trimester) and compared with 72 disease-matched and 748 nonteratogenic-exposed pregnancies. RESULTS There were significantly more miscarriages (adjusted odds ratio=1.94, 95% CI=1.08-3.48) and elective terminations of pregnancy (17/183 [9.3%] compared with 15/748 [2.0%]) in the lithium-exposed group compared with the nonteratogenic exposure group. The rate of major congenital anomalies after exclusion of genetic or cytogenetic anomalies was not significantly different between the three groups (lithium-exposed in the first trimester: 8/123 [6.5%]; bipolar: 2/61 [3.3%]; nonteratogenic: 19/711 [2.7%]). Cardiovascular anomalies occurred more frequently in the lithium group exposed during the first trimester when compared with the nonteratogenic exposure group (5/123 [4.1%] compared with 4/711 [0.6%]) but not after excluding anomalies that spontaneously resolved (3/123 [2.4%] compared with 2/711 [0.3%]). Ebsteins anomaly was diagnosed in one lithium-exposed fetus and in two retrospective lithium cases that were not included because contact with the information service was made after the prenatal diagnosis by ultrasound. The rate of noncardiovascular anomalies was not significantly different between the groups. The rate of preterm deliveries was higher in the lithium group compared with the nonteratogenic exposure group (18/131 [13.7%] compared with 41/683 [6.0%]). CONCLUSIONS Lithium treatment in pregnancy is associated with a higher rate of cardiovascular anomalies. Women who are treated with lithium during organogenesis should undergo fetal echocardiography and level-2 ultrasound.

Pregnancy outcome after in utero exposure to valproate : evidence of dose relationship in teratogenic effect.

AbstractBackground: Valproate is a first-line antiepileptic agent and is also used in the treatment of bipolar disorder and migraine. It is a known human teratogen. The objective of the study was to evaluate the teratogenic risk of valproate. Methods: All callers who contacted the Israeli Teratology Information Service (TIS) between 1994 and 2004 for information about gestational exposure to valproate were enrolled in the study. After the expected date of delivery, these women were followed up by telephone interview about their pregnancy outcome using a structured questionnaire. Data obtained from women who contacted the TIS about valproate exposure during pregnancy were then compared with data obtained from callers who were counselled for nonteratogenic exposures over the same timeframe. The main outcome measure was the rate of major congenital anomalies. Results: The outcomes of 154 valproate-exposed pregnancies (96.1% at least in the first trimester) were compared with those of 1315 pregnancies of women in the TIS database who were counselled for nonteratogenic exposures. The rate of major anomalies (some multiple) in the valproate group exposed in the first trimester was higher compared with controls after exclusion of genetic or cytogenetic anomalies (8 of 120 [6.7%] vs 31 of 1236 [2.5%], p = 0.018, relative risk [RR] = 2.66, 95% CI 1.25, 5.65). There were no cases of neural tube defect in the valproate-exposed group. Five of the eight major anomalies in the valproate group were cardiovascular, two of eight were mentally retarded, two of five male infants with major anomalies had hypospadias and three of eight were suspected of having fetal valproate syndrome. A daily dose ≥1000 mg was associated with the highest teratogenic risk (7 of 32 [21.9%] vs 31 of 1236 [2.5%], RR = 8.72, 95% CI 4.16, 18.30). In the subgroup exposed to polytherapy there was a 4-fold increase in the rate of major anomalies compared with controls. All major anomalies were in the group treated for epilepsy. Conclusion: When valproate treatment cannot be avoided in the first trimester of pregnancy, the lowest effective dose should be prescribed, preferably as monotherapy, to minimize its teratogenic risk.

Exposure to yellow fever vaccine in early pregnancy.

We report on a data collection concerning exposure to yellow fever vaccine (YFV) during early pregnancy, ascertained through the European Network of Teratology Information Services (TISs) and the Pharmacovigilance Department of Pasteur Merieux Connaught (PMC). Six TISs had had no inquiry about YFV. Five submitted prospectively collected cases. Seventy-four cases were analyzed, 58 with a completed follow-up. Pregnancies ended in 46 births, five voluntary abortions and seven spontaneous abortions. Three newborns had minor anomalies and two had major defects (ureteral stenosis and triphalangeal hallux). Although the sample is too small to rule out a moderate increased risk of adverse reproductive effect of YFV, it gives no argument for such an effect and should lead to reassure pregnant women who might be inadvertently vaccinated.

The outcome of pregnancy following topiramate treatment: A study on 52 pregnancies

In spite of a substantial increase in the use of topiramate at child bearing age, very little is known regarding its use in pregnancy. We describe the outcome of 52 pregnancies with 41 liveborn infants from which it seems that topiramate reduces birth weight without decreasing gestational age at delivery, but does not seem to increase the risk for structural defects. There was an increased rate of spontaneous abortions not related to the drug effects.

Methylphenidate in Pregnancy: A Multicenter, Prospective, Comparative, Observational Study

INTRODUCTION Methylphenidate is a central nervous system stimulant medicinally used in the treatment of attention-deficit disorder with or without hyperactivity (ADD/ADHD). Data on its use in human pregnancy are limited. The primary objective of the study was to evaluate the risk of major congenital anomalies after pregnancy exposure to methylphenidate for medical indications. METHODS In a prospective, comparative, multicenter observational study performed in 4 participating Teratology Information Services (in Jerusalem, Berlin, Newcastle upon Tyne, and Toronto) between 1996 and 2013, methylphenidate-exposed pregnancies were compared with pregnancies counseled for nonteratogenic exposure (NTE) after matching by maternal age, gestational age, and year at initial contact. RESULTS 382 methylphenidate-exposed pregnancies (89.5% in the first trimester) were followed up. The overall rate of major congenital anomalies was similar between the groups (10/309 = 3.2% [methylphenidate] vs 13/358 = 3.6% [NTE], P = .780). The rates of major congenital anomalies (6/247 = 2.4% [methylphenidate] vs 12/358 = 3.4% [NTE], P = .511) and cardiovascular anomalies (2/247 = 0.8% [methylphenidate] vs 3/358 = 0.8% [NTE], P = .970) were also similar after exclusion of genetic or cytogenetic anomalies and limiting methylphenidate exposure to the period of organogenesis (weeks 4-13 after the last menstrual period). There was a higher rate of miscarriages and elective terminations of pregnancy in the methylphenidate group. Significant predictors for the miscarriages using Cox proportional hazards model were methylphenidate exposure (adjusted hazard ratio [HR] = 1.98; 95% CI, 1.23-3.20; P = .005) and past miscarriage (adjusted HR = 1.35; 95% CI, 1.18-1.55; P < .001). CONCLUSIONS The present study suggests that methylphenidate does not seem to increase the risk for major malformations. Further studies are required to establish its pregnancy safety and its possible association with miscarriages.

Pregnancy outcomes after maternal varenicline use; analysis of surveillance data collected by the European Network of Teratology Information Services

Varenicline is a smoking cessation aid for which limited data exist concerning safety during human pregnancy. This multicentre prospective observational comparative cohort study was undertaken using surveillance data collected by the European Network of Teratology Information Services. The study sample consisted of 89 varenicline exposed pregnancies and two matched comparator groups; 267 non-teratogen exposed (NTE) controls and 78 exposed to nicotine replacement therapy or bupropion (NRT/B) for smoking cessation. For all exposed pregnancies, varenicline use only occurred in the first trimester, with a considerable proportion discontinuing use in the very early stages of pregnancy. The major congenital malformation rate (n=2/89, 2.25%) was in keeping with the expected background rate (2-4%), and was not significantly increased for first trimester varenicline-exposed infants in comparison with non-exposed controls (vs. NTE: OR 2.02, 95%CI 0.166 to 17.9, vs. NRT/B OR 0.874, 95%CI 0.0620 to 12.3). However, the small sample size produced very imprecise risk estimates.

Metoclopramide for nausea and vomiting of pregnancy: A Prospective Multicenter International Study

Metoclopramide is a dopamine receptor blocker that depresses the vomiting center in the brain. It readily crosses the term placenta, but whether appreciable placental transfer occurs in the first trimester is unclear. Because metoclopramide is used to treat nausea and vomiting in pregnancy, this prospective study examined the effects, if any, of intrauterine exposure to the drug in 175 women given metoclopramide who consulted six teratogen information centers in Israel, Italy, Brazil, and Canada. The control group included the same number of pregnant women consulting the same centers who used drugs known not to be embryotoxic or teratogenic. The groups were matched for age, smoking status, and alcohol consumption. Women were called 4 to 15 months after delivery. The daily dose of metoclopramide averaged 23 mg, and the mean duration of treatment was 10 days. Premature births were significantly more frequent in women taking metoclopramide (8.1% vs. 2.4%), but no increase in major malformations was noted after first-trimester exposure to the drug. When gross motor developmental milestones were monitored using the Denver Developmental Scale, no difference was found between infants of women taking metoclopramide and those of women taking other drugs. These findings suggest that women taking metoclopramide to combat nausea and vomiting in the first trimester of pregnancy probably are not at increased risk of spontaneous abortion or infant malformations.