Trisomy 13

Trisomy 13 is a chromosomal disorder in which all or a portion of chromosome 13 appears three times (trisomy) rather than twice in cells of the body. Also known as Patau Syndrome, this disorder was first identified by Dr. Klaus Patau in 1960. It is a syndrome involving multiple abnormalities, the range and severity of which may depend on the specific location of the duplicated (trisomic) portion of the chromosome and the percentage of cells containing the abnormality. In affected infants, abnormalities may include developmental delays, profound mental retardation, unusually small eyes (microphthalmia), an abnormal groove in the upper lip (cleft lip), incomplete closure of the roof of the mouth (cleft palate), undescended testes (cryptorchidism) in affected males, and extra (supernumerary) fingers and toes (polydactyly). Additional malformations of the head and facial area may also be present, such as a relatively small head (microcephaly) with a sloping forehead; a broad flat nose; widely set eyes (ocular hypertelorism); vertical skin folds covering the eyes' inner corners (epicanthal folds); scalp defects; and malformed, low-set ears. Some infants with Trisomy 13 Syndrome fail to grow or gain weight at the expected rate and have severe feeding difficulties, diminished muscle tone and episodes in which there is temporary cessation of breathing (apnea). The median survival time for infants with Trisomy 13 is 7 to 10 days. Thirty percent of infants with Trisomy 13 live to one month; 91% die within the first year of life [Rasmussen SA, et al, "Population-Based Analyses of Mortality in Trisomy 13 and Trisomy 18," Pediatrics, 111(4) (2003): 777-784]. In the United States, Trisomy 13 occurs in about 1 out of 10,000 live and still births [World Health Organization at: www.who.int/entity/genomics/about/en/trisomy13.pdf. (Accessed 2/25/04)]. However, the actual prevalence of Trisomy 13 is difficult to estimate because many pregnancies involving a prenatal diagnosis of Trisomy 13 are terminated shortly after the diagnosis has been made.

While the Ethical and Religious Directives for Catholic Health Care Services (ERDs) do allow for prenatal diagnosis, they do not allow for termination of pregnancies for the sole purpose of ending the life of a fetus diagnosed with genetic anomalies (nn. 45 and 50). Rather, the ERDs require that the right to life of the fetus be respected, whatever the condition of the fetus may be. The National Conference of Catholic Bishops (now called the U.S. Conference of Catholic Bishops) articulated this principle in a statement entitled, "Moral Principles Concerning Infants with Anencephaly," where they say, "…the rights of a mother and her unborn child deserve equal protection because they are based on the dignity of the human person whatever the condition of that person." In other words, directly terminating a pregnancy for the sole and immediate purpose of ending the life of an innocent person, no matter the age or condition of that person, would be inconsistent with the fundamental value of human dignity and the respect owed each human life in light of that dignity. While the ERDs do allow for the termination of pregnancy if the death of the fetus is a foreseen but unintended (i.e., indirect) consequence of an operation, treatment, or procedure whose immediate and directly intended effect is the cure of a proportionately serious pathological condition of the mother [n. 47], Trisomy 13 does not in and of itself constitute a pathological condition of the mother. Therefore, the induction of labor and delivery for the sole purpose of ending the life of a fetus with Trisomy 13 would not be consistent with respect for human dignity and would not be permitted by the ERDs.

Respect for human dignity does not, however, require using "aggressive" life-sustaining medical interventions in all circumstances. As articulated in Directive n. 57, the principle of Disproportionate Means does not require the use of particular medical interventions when the treatment in question does not offer a reasonable hope of benefit or entails excessive burdens to the patient or others. Thus, depending on the severity of the child's condition and prognosis, there may not be an obligation to use aggressive medical interventions to sustain the child's life at all costs, once born. Because the severity of anomalies associated with Trisomy 13 can vary significantly, this determination should not be made until the severity of the child's condition is known. Some children with less severe forms of Trisomy 13 can live many years (see, for example: http://www.LivingWithTrisomy13.org). Moreover, this determination should be based on the burdens and benefits of the treatment itself, not based on the perception that continued life itself imposes a burden on the child nor on the hardships imposed on parents by raising a "handicapped" child. As in all cases of surrogate decision-making in which the patient has never had decision-making capacity, the parents of a child with Trisomy 13 should make medical treatment decisions in accord with the best interest of the child.

Return to Issues & Concepts

Return to For the Public - Table of Contents

Return to For Affiliates - Table of Contents