The relationship between congenital defects and the use of exogenous progestional "contraceptive" hormones during pregnancy: a 20-year review

Evaluating emerging issues in epidemiology

Industry and government institutions need a credible approach for evaluating and responding to emerging public health issues. Representatives of industry, government, and academia met under the auspices of the International Life Sciences Institute's Health and Environmental Sciences Institute (HESI) to develop successful strategies for dealing with emerging issues based on historical case studies. The case studies chosen for evaluation were (1) tampon use and toxic shock syndrome; (2) hazardous waste and childhood cancer risk in Toms River, New Jersey; (3) fenfluramine and phentermine use and valvular heart disease; (4) silicone breast implants and cancer and auto-immune disease; and (5) progestational drugs and birth defects. We identified eight lessons from these case studies. Foremost, we recommend that public and private institutions not defer action until an issue is scientifically resolved and stress that cooperation among issue stakeholders is critical for effective issue resolution. We suggest establishing a research program as an effective way to assure that good science is included in resolution of the issue. We further recommend frequent and timely communication with all stakeholders, and the development of research approaches to fill gaps when the scientific data on an issue are limited.

Nongenital malformations following exposure to progestational drugs: The last chapter of an erroneous allegation

In the late 1960s and 1970s, a number of epidemiological studies were published indicating that pregnant women who were exposed to an array of sex steroids delivered infants with an increased incidence of nongenital congenital malformations. Because of these publications, the Food and Drug Administration (FDA), in conjunction with various pharmaceutical companies, labeled the therapeutic exposure of progestational drugs and contraceptives in pregnant women as a risk factor for limb-reduction defects (LRDs) and congenital heart defects (CHDs). Subsequently there was a rapid decrease in the exposure of pregnant women to these drugs and the initiation of numerous lawsuits alleging that a particular progestational drug was responsible for a child's nongenital congenital malformation. Wilson and Brent (1981) published an article indicating that epidemiological and animal studies of these drugs, and basic science did not support the package insert's warnings. Many new and previous animal and epidemiological studies did not support the FDA box warning. In 1987 the FDA held a hearing in which the FDA, the Teratology Society, the Centers for Disease Control and Prevention, the American College of Obstetrics and Gynecology, and other organizations supported the position that progestational agents did not result in nongenital malformations. An editorial appeared in Teratology congratulating the FDA for removing the warning label on oral contraceptives regarding nongenital malformations. In 1999 the FDA published new wording for package inserts that removed warnings for nongenital malformations for all progestational agents. In spite of the recent changes in the package inserts, lawsuits have alleged that progestational drugs cause nongenital malformations. It took 22 years from the time a box warning was required by the FDA until the warnings were removed in 1999. The 1999 FDA publication, which is a scholarly and objective document, should put an end to 2 decades of concern and anxiety for pregnant women or women of reproductive age. Could scientists, the pharmaceutical companies, or the FDA have prevented the mislabeling of progestational drugs with regard to their teratogenic risks? Was the epidemiological or teratology community at fault because they did not critique and respond to the early publications? Did the FDA act too slowly? The epidemiologic analyses, animal studies, and basic science principles have been reviewed, and it is obvious that clinically utilized progestational drugs do not cause nongenital malformations (i.e., LRDs and CHDs).

Congenital cardiovascular malformations: questions on inheritance. Baltimore-Washington Infant Study Group

The Baltimore-Washington Infant Study, an epidemiologic investigation of congenital heart disease, searches for genetic and environmental risk factors. Among 2,102 infants with heart disease, 17.5% had a noncardiac abnormality of chromosomal or genetic origin, whereas among 2,328 control infants, only 0.7% had a genetic abnormality. Familial cardiovascular malformations encountered can be grouped into five distinct etiologic mechanisms. Single gene effects may be responsible for the specific histologic and biochemical changes in familial atrial septal defect with conduction disturbance and also in idiopathic ventricular hypertrophy. Left heart lesions showed familial concordance by the presumed morphogenetic mechanism of abnormal embryonic blood flow with phenotypes of varying severity. Pulmonary stenosis appeared with familial heritable disorders, as well as a partially concordant lesion with tetralogy of Fallot. Ventricular septal defect with transposition of the great arteries (one sibling pair) and with truncus arteriosus (two sibling pairs) indicate forme fruste expression of conotruncal defects. Endocardial cushion defect occurred with and without Down's syndrome in members of three families, suggesting inheritance of a defect affecting cellular migration. Heritable blood coagulopathies occurred in case families and not in control families. The associated of hemophilia and transposition, observed also by others, is extremely unlikely by chance and suggests genetic errors of endothelial cell function. The description of specific families from a population-based study emphasizes biologic questions on the nature of the inheritance of cardiovascular malformations.

Evaluation of the use of Proluton-Depot (hydroxyprogesterone hexanoate) in early pregnancy

This study evaluates the effect of treatment with Proluton-Depot (hydroxyprogesterone hexanoate) in early pregnancy, and the final outcome of pregnancy and fetal status. One hundred and fifty patients received intramuscular injection of Proluton-Depot from 6 weeks to 8 weeks to 16 weeks to 18 weeks gestation. The outcome of this treated group was compared with a similar number of 150 patients with similar problems, but the second group received no hormonal treatment. There was no evidence to suggest that Proluton-Depot had any adverse effect on the infant or the final outcome of pregnancy.

Congenital abnormalities and hormones during pregnancy: a clinical review

A review of the extensive literature on the subject indicates that sex hormones have been associated with a wide variety of adverse clinical conditions following usage during pregnancy. About 230 cases of female pseudohermaphroditism have been reported following use of hormones with androgenic potency, but masculinization observed with estrogens in a few females may represent only adrenal-stimulated pseudohermaphroditism. Feminization of males, mostly by progestogens in some 45 cases, is unproven at present. Realizing the limitations of the published studies when all present data are considered, there seems no justification for undue concern over the induction of nongenital congenital malformations through hormone use in pregnancy. The available data on the association to cardiac, limb, and CNS defects, and to several malformative syndromes, are not convincing: the effects appear to be remarkably nonspecific, the studies are contradicted by a large number of negative reports, and an increased incidence of defects with increased usage has not materialized. A possible exception are the CNS malformations associated with the use of the antifertility agent clomiphene, and careful surveillance is warranted at present. While a reasonable interpretation from this review would be that hormones present no major teratogenic hazard, elimination of hormonal exposure whenever possible during pregnancy is suggested.

Maternal hormone therapy and congenital heart disease

Exogenous female sex hormone exposure was studied in the mothers of 110 infants with conotruncal malformations of the heart, born in the years 1972-75. Cases were ascertained throughout the referral area of the Maryland State Intensive Care Neonatal Program. For each case, three normal controls were chosen from the birth population: Two matched on eight characteristics related to the likelihood of hormone-taking (race, maternal age, parity, fetal losses, gestational age, delivery mode, time of prenatal registration, private/service), and one also on the infant's sex and birthweight; the third control was chosen at random. In personal interviews, information was obtained on the mother's general health, family history, reproductive characteristics, pregnancy health, and environmental exposures. Identification of hormonal products was aided by a display of pills and packages. Maternal recall was examined in comparison to the responses of a group of mothers of infants with hypoplastic left heart ("disease controls"). Regression analysis on time elapsed since the infant's birth revealed no difference in recall between the mothers of cases and of controls. Multilogistic regression analysis, controlling for confounding variables and for scores constructed for reproductive, malformation, and exposure risks, showed no increase in relative risk for cases when compared with matched controls. When compared to random controls, the analysis suggested a possible increase in relative risk with increased environmental exposure scores; components of the risk score were excess smoking and alcohol intake, exposure to X-ray, drugs, paints, insecticides, and chemicals. The possible significance of this finding needs to be further investigated.

Current status of immunologic pregnancy tests

Information about the mechanism of various pregnancy tests is summarized. The sensitivity of these tests as well as their advantages and limitations in a clinical setting are presented and evaluated in an effort to maximize their usefulness in a clinical setting.

Use of contraceptives prior to and after conception and exposure to other fetal hazards

In a large prospective study, set up to determine whether reproductive outcomes are affected by prior contraceptive use, 34,344 women were recruited at their first antenatal visit and followed until pregnancy termination. This paper summarizes the study methods and describes the demographic differences between subjects who used various contraceptives shortly before conception, and those who experienced contraceptive failures. Thirty percent of the women had used oral contraceptives (OCs) during the 5 months prior to conception and 2.4% had continued using them after their LMP. IUDs had been used by 5.8% of women before conception and 1.1% after. If these rates are also true for the whole population of the U.S., they indicate that approximately 70,000 babies are born each year following pill-failures and 30,000 following failures of IUD's. Exposure to other fetal hazards was common, with 48% of pregnant women drinking alcohol, 28% smoking, and 15% receiving diagnostic X-rays. OC use was more common among smokers and drinkers, and OC failures were significantly associated with the use of anti-epileptics, aspirin, and with exposure to radiation.