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Abstract: Prenatal testing that will benefit the health of the mother or fetus is permitted (and even encouraged) in Jewish law. Testing to determine fetal problems for which the solution is termination of pregnancy is controversial, as abortion to prevent the birth of an ill fetus is generally not permitted. The couple should be counseled as to the availability of prenatal tests in keeping with their halachic framework. They should be given the chance to think through the risk/ benefit ratio of even non invasive procedures, prior to their being performed.
Discussion:
Prenatal Maternal Testing
All routine tests whose purpose is to assure the health of the mother pose no halachic problems and should be performed. This includes blood pressure monitoring and screening for diabetes and preeclampsia. Occasionally, women who have had many children will not see the need for of such testing and allow other family obligations to lead to poor compliance with testing. The importance of such testing should be stressed [1].
Prenatal Genetic Testing
Testing for genetic diseases can be done at different stages of life. Each raises its own halachic concerns. When testing is done prior to marriage, there is a concern that it could lead to the dissolution of an otherwise appropriate union. Furthermore, misconceptions about the significance of carrier status might lead to difficulty in finding a mate even if there is no medical reason to fear the birth of an affected child. When the testing is done after marriage, there is concern that it might inhibit the couple from having children. If the testing is done after conception there is the concern that it might lead to an abortion.
Anonymous carrier testing done prior to engagement alleviates the above concerns. Within the Jewish community, a system of premarital genetic testing for a number of conditions has been established. This project is called Dor Yesharim, The Committee for Prevention of Jewish Genetic Diseases (718-384-2332 in the U.S., or 972-2-537-2111 in Israel). Dor Yesharim currently performs carrier tests for Tay-Sachs, Canavan, Fanconis Anemia, familial dysautonomia (FD), Bloom's syndrome, Glycogen Storage Disease (GSD) and Cystic Fibrosis.
Individuals are tested before beginning the search for a marriage partner, but are not told the results of the test. A couple considering marriage notifies Dor Yesharim and is informed whether or not there is a problem. The couple is not told what disease they carry, just that the match is likely to lead to a child affected by one of these conditions.
As this system takes the halachic concerns into consideration, it has the approval of many leading halachic authorities. It is also subsidized. However, Dor Yesharim will only test people prior to an official engagement, and does not give specific test results. Therefore, some couples will choose to have the testing done privately.
If a couple has not been tested prior to marriage, they should consult with their rabbi about doing tests at a later point. There are grounds to permit testing at any stage if it could lead to an intervention that would be beneficial to the health of the fetus.
Alpha Fetoprotein (AFP) or Triple Test
This test is done only while a woman is pregnant, generally between 14-17 weeks of gestation [2]. The test itself is a non-invasive blood test, and presents no halachic problem of additional risk to the fetus or the mother. However, the couple should be fully cognizant of the reasons for testing and the implications of the results, so they can discuss them further with their rabbi.
Most rabbis would permit AFP to screen for anencephaly or spina bifida. While a specific question must be asked, it is quite likely that pregnancy interruption would be permitted for anencephaly as the fetus has no life expectancy. Allowing abortion for spina bifida would be a much more difficult question. However, advance knowledge of spina bifida can affect the choice of the method or location of delivery to enable optimal treatment for the baby [2] [3]. There is room to permit the test for this reason.
Using the triple test to screen for Down Syndrome is a matter of halachic debate. The couple should be made aware of the accuracy and implications of this test before it is performed [4] [5]. They can then consult with their rabbi to decide what they would do with the results.
Ultrasound for Prenatal Screening
Ultrasound can be used at many points during pregnancy. Nuchal cord thickness (described below) is generally done early (around 10 weeks of gestation) but can also be done later. A survey of systems is often recommended at 20 weeks of gestation [6]. There is generally little halachic objection to the use of ultrasound examinations during pregnancy. Information obtained from this procedure can often be used to influence the care of the fetus [7] [8], and not just to identify malformations that would raise the possibility of abortion.
Performance of a vaginal ultrasound does not render a women niddah. However, women may express concern about the possibility that the exam could cause bleeding. Should bleeding occur, the physician should indicate what the most likely source is, so that she can ask her rabbi how to proceed.
Nuchal Cord Thickness
The halachic issues raised by measuring nuchal cord thickness to screen for Down syndrome are similar to those for other ultrasound examinations. The couple should be made aware of the accuracy and implications of this test before it is performed [9]. They can then consult with their rabbi to decide what to do with the results. If the rabbi will not permit a follow up test, measuring nuchal cord thickness alone is of questionable value [10].
Other Non-invasive Tests
As additional tests become clinically available, the new information should be presented to the patients and their rabbis. However, the implications of test results should be discussed with the patients before they are performed. This can prevent raising anxiety about fetal malformation in a situation where more invasive tests will not be permitted.
Invasive Tests: Amniocentesis and Chorionic Villi Sampling
Halachic authorities differ regarding the permissibility of invasive prenatal tests (amniocentesis and chorionic villi sampling). Much of the debate focuses on how the test results could be used productively, and especially on whether abortion would be permitted if a genetic defect were found.
Many authorities would allow abortion in cases where the fetus is clearly not viable, such as Trisomy 18. If there is reason to suspect such a condition [11], invasive tests would be permitted. Even though recent studies indicate that this condition may be detected on ultrasound alone [12], a rabbi may request an invasive test for confirmation prior to deciding to permit an abortion.
When invasive tests are used to screen for conditions like Down syndrome, where abortion is generally not permitted, rabbinic authorities differ. Some maintain that, since abortion is not an option, one should not increase the risk of miscarriage with an invasive test. Others consider the test worthwhile because in most cases the fetus is not affected [13] and the parents can be reassured about this issue [14]. Even if the fetus is affected, the family may be better able to cope if they are prepared in advance [14]. A couple considering these tests should discuss them with their rabbi before they are performed.
Chorionic villi sampling (CVS) used to be done as early as six weeks of gestation. This was helpful for religious couples, as it was just possible to get results within 40 days after mikveh immersion, when it is easier to permit abortion. However, due to the risk of limb defects, the test is no longer performed quite so early in pregnancy [15] and this advantage is lost. CVS continues to have the advantage that it can be performed early enough that a woman can still hide her pregnancy [13]. This needs to be balanced against the slightly higher risk of miscarriage than that for amniocentesis [13]. The couple should ask for the statistics for the center where the procedure is done prior to consulting with the rabbi.
Amniocentesis is performed via the abdomen and is unlikely to cause vaginal bleeding [16]; therefore, it does not render a woman niddah. There is debate as to whether CVS makes a woman niddah. This question should be asked prior to its performance.
Pre-implantation Genetic Diagnosis
Each couple considering this procedure must ask an individual halachic question. Where there is a known family history of a genetic defect, it is likely that IVF will be permitted to allow pre-implantation genetic diagnosis. It is halachically much easier to allow implantation of unaffected fetuses than to allow abortion.
Implications for Care: Prenatal diagnosis is not in itself prohibited by Jewish law. However, a full discussion of the implications of each test should be performed prior to embarking on testing so the couple can think through the risk benefits of such testing in the context of their halachic beliefs. Such careful counseling would be of benefit to all patients [17].
Preconception testing presents fewer halachic problems than testing while the woman is already pregnant, as PGD is easier to permit than is abortion.
Abortion is not easily permitted for a malformed but viable fetus. However, as halacha is case law, an individual question should always be asked.
Medical References
[1] Carroli G, Rooney C, Villar J. How effective is antenatal care in preventing maternal mortality and serious morbidity? An overview of the evidence. Paediatr Perinat Epidemiol 2001;15 Suppl 1:1.
[2] ACOG practice bulletin. Clinical management guidelines for obstetrician-gynecologists. Number 44, July 2003. (Replaces Committee Opinion Number 252, March 2001). Obstet Gynecol 2003;102:203.
[3] Wilkins-Haug L. Considerations for delivery of infants with congenital abnormalities. Obstet Gynecol Clin North Am 1999;26:399-412. (Level III)
[4] Wald NJ, Kennard A, Hackshaw A, McGuire A. Antenatal screening for Down's syndrome. J Med Screen 1997;4:181.
[5] Dugoff L, Hobbins JC, Malone FD, et al. Quad Screen as a Predictor of Adverse Pregnancy Outcome. Obstet Gynecol 2005;106:260.
[6] ACOG Practice Bulletin No. 58. Ultrasonography in pregnancy. Obstet Gynecol 2004;104:1449.
[7] Simpson LL, Malone F, Bianchi B, et al. Nuchal translucency and the risk of congenital heart disease - a population-based screening study (The FASTER Trial). Am J Obstet Gynecol 2004;191:S2.
[8] Donoghue E, Smulian J. Prenatal ultrasonography: Implications for the general pediatrician. Contemporary Pediatrics 2002;1:29.
[9] Nicolaides, KH. Nuchal translucency and other first-trimester sonographic markers of chromosomal abnormalities. Am J Obstet Gynecol 2004;191:45.
[10] ACOG Committee Opinion #296: First-Trimester Screening for Fetal Aneuploidy. Obstet Gynecol 2004;104:215.
[11] Bahado-Singh RO, Choi SJ, Oz U, et al. Early second-trimester individualized estimation of trisomy 18 risk by ultrasound. Obstet Gynecol 2003;101:463.
[12] Oyelese Y, Vintzileos AM. Is second-trimester genetic amniocentesis for trisomy 18 ever indicated in the presence of a normal genetic sonogram? Ultrasound Obstet Gynecol 2005;26:691.
[13] Medical Research Council European trial of chorion villus sampling. MRC working party on the evaluation of chorion villus sampling. Lancet 1991;337:1491.
[14] Green JM, Hewison J, Bekker HL, Bryant LD, Cuckle HS. Psychosocial aspects of genetic screening of pregnant women and newborns: a systematic review. Health Technol Assess 2004 Aug;8(33):iii, ix-x, 1-109.
[15] Olney RS, Khoury MJ, Alo CJ, et al. Increased risk for transverse digital deficiency after chorionic villus sampling: results of the United States Multistate Case-Control Study, 1988-1992. Teratology 1995;51:20.
[16] Nassar AH, Martin D, Gonzalez-Quintero Gomez-Marin O, Salman F, Gutierrez A, et al. Genetic amniocentesis complications: is the incidence overrated? Gynecol Obstet Invest 2004;58:100-4.
[17] Royal College of Obstetricians and Gynaecologists. Report of the working party on biochemical markers and the detection of Down's syndrome. London: RCOG Press, 1993.
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