Teratogenicity of misoprostol: data from the Latin-American Collaborative Study of Congenital Malformations (ECLAMC)

Prevalence of congenital anomalies and prenatal diagnosis by birth institution (public vs. non-public): indicators of inequality in access to elective termination of pregnancy for fetal anomalies

Congenital anomalies (CA) encompass all morphological or functional alterations originating prenatally and present at birth. The prenatal diagnosis of these anomalies can significantly impact the overall health of the pregnant individual and may influence her decision regarding the continuation of the pregnancy. In contexts where safe pregnancy termination is not guaranteed by the state, it can lead to unsafe procedures with severe consequences. In our research, we analyzed epidemiological information on CA to develop potential indicators of inequity in access to safe abortion prior to the legalization of legal termination of pregnancy in Argentina. We included cases from 13 public hospitals and 9 non-public subsector hospitals, from the period 2013-2020. Two groups of specific CA were selected: 1) CA capable of being prenatally diagnosed, and 2) CA related to vascular disruptive events. 10/18 of the selected CA capable of being prenatally diagnosed had a significantly higher prevalence in public hospitals (anencephaly, encephalocele, spina bifida, microcephaly, hydrocephalus, holoprosencephaly, hydranencephaly, diaphragmatic hernia, gastroschisis, bilateral renal agenesis). Non public hospitals had higher prenatal detection. Birth prevalence of CA related with vascular disruptive events (limb reduction, Moebius syndrome, amniotic band sequence) were significantly higher in public hospitals. These results suggest disparities in access to prenatal diagnosis and safe abortion based on socioeconomic status. There was a significant gap in access to prenatal diagnosis for CA and possibly to safe elective abortion depending on the type of institution (public vs. non-public).

Isolated antenatal hydrocephalus after foetal exposure to misoprostol : a teratogenic effect of the cytotec® ?

Misoprostol is often used for termination of pregnancy in France and others countries. However, some pregnancies are continued after taking the drug and congenital malformations are known to be the consequence of fetal exposure to misoprostol, among then hydrocephalus. The type of hydrocephalus in case of misoprostol exposure is not known. We report the first case in the literature of an obstructive hydrocephalus due to an aqueduct of Sylvius stenosis diagnosed during the pregnancy after misoprostol intake. The possible physiopathological implications of the drug are discussed regarding the genesis of this malformation.

Nasoethmoidal meningocele in a child presenting bilateral congenital cystic adenomatoid malformation: Evidence for a new entity or consequence of gestational exposures?

BACKGROUND

Nasoethmoidal meningocele is considered an uncommon type of cephalocele, and congenital cystic adenomatoid malformation (CCAM) is a rare lung disorder characterized by overgrowth of the terminal bronchioles.

CASE

We report the unusual association between a nasoethmoidal meningocele and CCAM type II in a fetus exposed to valproic acid and misoprostol. The mother was an 18-year-old woman on her first pregnancy. She had a history of absence seizures since she was 5 years old. She took valproic acid from the beginning of the gestation until the end of the third month. At the end of the third month, she attempted interruption of her pregnancy using misoprostol. The fetal nasoethmoidal meningocele and CCAM type II were identified through morphological ultrasound examination and magnetic resonance imaging. A genome-wide study detected one copy number variation classified as rare, entirely contained into the SPATA5 gene. However, it does not seem to be associated to the clinical findings of the patient.

CONCLUSION

To our knowledge, there is only one case reported in the literature showing the same association between a nasoethmoidal meningocele and CCAM. Thus, the malformations observed in our patient may be related to the gestational exposures. Also, we cannot rule out that the patient may present the same condition characterized by a cephalocele and CCAM described by some authors, or even an undescribed entity, because some hallmark features, such as laryngeal atresia and limb defects, were not observed in our case. Further reports will be very important to better understand the associations described in our study.

Risk of drug-induced congenital defects

Defects attributable to drug therapy represent about 1% of congenital defects of known aetiology. This means that a precautionary attitude and correct use of drugs in fertile, and especially pregnant, women is a feasible form of prevention. Drugs currently in use with proven teratogenic effect number approximately 25, but new pharmaceutical drugs are constantly in preparation. Recognition of a drug-induced teratogenic effect is a complex procedure taking into account not only experimental animal data but also experience in humans. Considering that 40% of pregnancies are not planned, it follows that any drug with known or suspected teratogenic potential must be used only under strict medical control. Also, adequate knowledge on potential teratogenicity of a drug permits modification of therapy before conception. It goes without saying that any drug should be used during pregnancy only if it is essential, and it would be prudent to use only those where adequate information is provided and prior clinical experience is available. Teratology Information Services can assist both physicians and patients when any doubt exists.

Methotrexate/misoprostol embryopathy: Report of four cases resulting from failed medical abortion

Methotrexate, a methyl derivative of aminopterin, is a folic acid antagonist and a known human teratogen; misoprostol is a synthetic prostaglandin E1 analog that causes uterine contractions. Recently, there has been resurgence in the use of methotrexate in combination with misoprostol or of methotrexate alone for the treatment of unwanted or ectopic pregnancies, respectively. This report documents the findings in four infants who were exposed prenatally to methotrexate alone or in combination with misoprostol in a failed attempt at medical abortion or treatment of ectopic pregnancy. All patients demonstrated growth deficiency, with growth parameters <10th centile, and all displayed features consistent with methotrexate and/or misoprostol embryopathy. Since an increasing number of medical abortions are being performed, it is important for physicians to recognize the associated teratogenic effects of these abortifacients. Data from the patients herein described should prompt obstetricians and other health care practitioners who prescribe these medications to counsel their patients regarding these risks, especially if the treatment regimen fails to induce an abortion.

Prenatal exposure to misoprostol and vascular disruption defects: a case-control study

Prenatal exposure to misoprostol has been associated with Moebius and limb defects. Vascular disruption has been proposed as the mechanism for these teratogenic effects. The present study is a multicenter, case-control study that was designed to compare the frequency of prenatal misoprostol use between mothers of Brazilian children diagnosed with vascular disruption defects and matched control mothers of children diagnosed with other types of defects. A total of 93 cases and 279 controls were recruited in eight participating centers. Prenatal exposure was identified in 32 infants diagnosed with vascular disruption defects (34.4%) compared with only 12 (4.3%) in the control group (P<0.0000001). Our data suggest that prenatal exposure to misoprostol is associated to the occurrence of vascular disruption defects in the newborns.

Epidemiological assessment of misoprostol teratogenicity

OBJECTIVE

To verify if any of the 15 congenital defects already reported in association with misoprostol can be found within an epidemiological registry of congenital defects.

DESIGN

Case-control study including case-sick and case-health controls.

METHODS

Comparison of misoprostol exposure for each specific defect, using the exposure for the rest of defects as a reference group.

POPULATION

Four thousand six hundred seventy-three consecutive newborn infants with malformations of unknown aetiology, in the Latin American Collaborative Study of Congenital Malformation.

RESULTS

There was no difference in exposure rate between the malformed (34/4,673) and nonmalformed (23/4,980) newborns. Four of the five more frequently cited defects in the literature were found to be in excess: constriction ring, terminal transverse-limb defects, hydrocephalus, and arthrogryposis. Equinovarus feet had a normal frequency in our study. Thirteen different defects not described in the literature were seen in our misoprostol exposed cases, but only holoprosencephaly and bladder exstrophy significantly exceeded the expected number.

CONCLUSIONS

The confirmation from an epidemiological registry of an association for four of the five more commonly observed congenital defects among misoprostol exposed children described in the literature seems indicative of a real teratogenic effect. The defects are of vascular disruption type. However, additional attempts to achieve abortion could not be excluded as a concurrent contribution.

Pregnancy outcome after exposure to misoprostol in Brazil: a prospective, controlled study

BACKGROUND

Misoprostol, a synthetic prostaglandin E1 analog is labeled for the treatment of gastric and duodenal ulcers. In Brazil, where abortion is not a legal procedure, there is a widespread popular misuse of this drug in abortion attempts. This misuse and the fact that, in many cases the desired pregnancy termination does not occur, raise concerns about fetal safety. Case reports of congenital anomalies after maternal use of misoprostol have been published. The objective of this work was to compare pregnancy outcome following misoprostol exposure with a matched control group. This is the first prospective controlled study on fetal safety after misoprostol use.

METHODS

A prospective, observational cohort study with 86 exposed and 86 pair-matched, non-exposed controls.

RESULTS

There was no significant difference in the rates of major or minor birth between exposed compared to non-exposed infants (2/67 vs 2/81, major defects; 7/67 vs. 3/81, minor anomalies) There were significantly more miscarriages in the exposed group (17.1% vs. 5.8%; relative risk, 2.97; 95% confidence interval, 1.12 to 7.88). There was no statistical difference in gestational age at delivery, birth weight, sex ratio, rate of prematurity, low birth weight, or rates of cesarean section between groups.

CONCLUSIONS

Our study, despite its limited statistical power, does not suggest a potent teratogenic action of misoprostol exposure during pregnancy.

Use of misoprostol during pregnancy and Möbius' syndrome in infants

BACKGROUND

Patients with upper gastrointestinal ulceration may be treated with misoprostol, but it is not recommended for pregnant women because it may stimulate uterine contractions and cause vaginal bleeding and miscarriage. Recent data from Brazil, where misoprostol is used orally and vaginally as an abortifacient, have suggested a relation between the use of misoprostol by women in an unsuccessful attempt to terminate pregnancy and Möbius' syndrome (congenital facial paralysis) in their infants.

METHODS

We compared the frequency of misoprostol use during the first trimester by mothers of infants in whom Möbius' syndrome was diagnosed and mothers of infants with neural-tube defects in Brazil. All diagnoses in infants were made between January 16, 1990, and May 31, 1996, by clinical geneticists at seven hospitals who also interviewed the mothers and recorded information about the administration of misoprostol, among other data.

RESULTS

We identified 96 infants with Möbius' syndrome and matched them with 96 infants with neural-tube defects. The mean age at the time of the diagnosis of Möbius' syndrome was 16 months (range, 0.5 to 78), and the diagnosis of neural-tube defects was made within 1 week of birth in most cases. Among the mothers of the 96 infants with Möbius' syndrome, 47 (49 percent) had used misoprostol in the first trimester of pregnancy, as compared with 3 (3 percent) of the mothers of the 96 infants with neural-tube defects (odds ratio, 29.7; 95 percent confidence interval, 11.6 to 76.0). Twenty of the mothers of the infants with Möbius' syndrome had taken misoprostol only orally (odds ratio, 38.8; 95 percent confidence interval, 9.5 to 159.4), 20 had taken misoprostol both orally and vaginally, 3 had taken the drug vaginally, and 4 did not report how they took the drug.

CONCLUSIONS

Attempted abortion with misoprostol is associated with an increased risk of Möbius' syndrome in infants.