La cara desconocida de la fecundación in vitro


José María Pardo Sáenz, Dr.


El propósito de este artículo es mostrar la cara oculta de los métodos artificiales de reproducción humana. En general, las clínicas de fertilización humana sólo muestran la cara más atractiva de la fecundación in vitro: el recién nacido. Sin embargo, nunca muestran la otra cara: el largo y dramático proceso que está detrás. Tras hacer una breve referencia a la contribución del Premio Nobel de Medicina Robert Edwards 2010, padre de la fecundación in vitro, se analizan las dos raíces que sostienen el gran árbol de los métodos artificiales de reproducción humana: el cientificismo y el sentimentalismo. A continuación se estudia el aspecto ético de estos procedimientos. Hemos concluido en un juicio éticamente negativo sobre estas técnicas, ya que distorsionan el significado de la sexualidad humana y del acto conyugal. A continuación se analizan algunas de las consecuencias más frecuentes de estos métodos: "la mortalidad embrionaria" asociada con estas técnicas; "la congelación de los embriones sobrantes"; "los riesgos para la salud", tanto del bebé como de la mujer. Todos estos elementos los debe tener en cuenta la pareja para tomar la decisión más libre y responsable que sea posible.

Por último, se explica la "pendiente resbaladiza" en el uso de estas técnicas (los niños medicados, los niños a la carta, la maternidad de alquiler y el mercantilismo reproductivo): lo que se ha desarrollado con una clara intención de resolver el problema de la infertilidad, con toda certeza ha abierto también nuevos y grandes problemas éticos.


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Cómo citar
Pardo SáenzJ. (2021). La cara desconocida de la fecundación in vitro. Revista De Medicina Y Ética, 23(3), 397-415. Recuperado a partir de


1 Escolios address to Dionisio Areopagita (PG, 4, 536); cfr. DIONISIO AREOPAGI- TA. Letter VI (PG, 3, 1077).
2 CONGREGATION FOR THE DOCTRINE OF THE FAITH. Instruction “Donum vi- tae” (22.II.1987), conclusion.
3 Edwards’ research work started in 1960 with the study of human fertilization. Eig- ht years later, he and his colleague Steptoe, gynecologist at General Hospital at Oldham (UK), achieve the fertilization of an egg in the laboratory. The question of artificial reproduction was, at the beginning of the 1970s, a very controversial is- sue. A good number of people and scientists opposed this kind of research and accused the responsible of wanting to play god.
This works were not even accepted from the practical point of view since one of the problems of the time was the over population alarm and not infertility. In fact, two years before the first egg was fertilized in the laboratory, Edwards and Steptoe had to raised the money to finance their research on human reproduction in the private sector since public funds were denied (among them was the Medical Re- search Council).
4 JOHN PAUL II. Encyclical “Redemptor Hominis” (4.III.1979), n. 16.
5 ID. Encyclical “Evangelium vitae” (25.III.1995), n. 17.
6 “Scientism” is the philosophical notion which refuses to admit the validity of forms of knowledge other than those of the positive sciences; and it relegates religious, theological, ethical and aesthetic knowledge to the realm of mere fantasy (...). Re- grettably, it must be noted, scientism consigns all that has to do with the question of the meaning of life to the realm of the irrational or imaginary (...). And since it leaves no space for the criticism offered by ethical judgement, the scientistic men- tality has succeeded in leading many to think that if something is technically possi- ble it is therefore morally admissible”. ID. Encyclical “Fides et ratio” (14.IX.1998), n. 88.
7 Cfr. BENEDICT XVI. Lecture by the Holy Father Benedict XVI at the University of Rome “La Sapienza” (17.I.2008); ID. Encyclical “Caritas in veritate” (29.VI.2009), n. 70.
8 Cfr. CONGREGATION FOR THE DOCTRINE OF THE FAITH. Instruction “Digni- tas personae” (12.XII.2008), n. 16.
9 Cfr. JOHN PAUL II. Encyclical “Veritatis splendor” (6.VIII.1993), nn. 78 and 79.
10 Cfr. CONGREGATION FOR THE DOCTRINE OF THE FAITH. Instruction Digni- tas personae (12.XII.2008), n. 12. For more information regarding the truth and meaning of human sexuality and the conjugal act, cfr. SARMIENTO A. El matrimo- nio cristiano. Pamplona: Eunsa; 20073:35ss.
11 Cfr. PARDO JM. Bioética práctica al alcance de todos. Madrid: Rialp; 2004: 51. 12 Cfr. WENNERHOLM UB, SÖDERSTRÖM-ANTTILA V, BERGH C, ET AL. Chil- dren born after cryopreservation of embryos or oocytes: a systematic review of outcome data. Human Reproduction 2009; 24(9): 2158-2172. It is estimated that 250.000 babies are born in test tubes worldwide. 20073: 35ss.
13 The success rate, understood as newborn alive, is about 27%. Cfr. GUNBY J, BISSONNETTE F, LIBRACH C, COWAN L. Assisted reproductive technologies (ART) in Canada: 2006 results from the Canadian ART Register. Fertility and Ste- rility 2010; 93(7): 2189-2201. Very similar data from Australia are taken from this other article: STEWART LM, D’ARCY C, HOLMAN J, ET AL. How effective is in vitro fertilization, and how can it be improved?, Fertility and Sterility 2011; 95(5): 1677-1683, where the average effectiveness of IVF is about 45%, although it drops to 20-30% in women around 40-44 years old. This European article mentio- ns only the rate of pregnancies, nor the one for babies born alive: DE MOUZON J, GOOSSENS V, BHATTACHARYA S, ET AL. Assisted reproductive technology in Europe, 2006: results generated from European registers by ESHRE. Human Re- production 2010; 25(8): 1851-1862, shows the data obtained in 32 European countries which includes 998 assisted reproduction clinics and 458.759 treatment cycles out of which 117.318 are IVF and 232.844 are ICSI. When IVF was used, the rate of pregnancies was of 29-32%, and of 29.9-33% for the ICSI. In Spain, the pregnancies achieved by treatment cycle 25-36%: CASTILLA JA, HERNÁNDEZ E, CABELLO Y, ET AL. Assisted reproductive technologies in public and private cli- nics. Reproductive BioMedicine Online. December 2009; 19(6): 872-878. As for as I am concerned, the important fact is not the babies born – accumulated cycle’s ratio but the number of babies born and the number of embryos produced. On this regard, Patrizio and Sakkas use a new parameter to evaluate the efficiency of as- sisted reproductien methods: the number of born babies in relation to the number of egg extracted and use. This means that the efficiency of the method is 4.6%. Cfr. PATRIZIO P, SAKKAS D. From oocyte to baby: a clinical evaluation of the biological efficiency of in vitro fertilization. Fertility and Sterility 2009; 91(4): 1061- 1066. In conclusion: any other medical procedure with this percentage of failure (in some cases up to 73%) would hardly be considered an important breakthrough in the battle against disease regardless the fact of being a wonder of technique itself.
14 Over 80% of the embryos produced in vitro and transferred to the uterus do not have the possibility to develop normally, due to the fact that they have some kind of cromosomic or genetic defect. Cfr. CAPLAN A, PATRIZIO P. Beginning of the end of the “embryo wars”. Lancet 2009; 373(9669): 1074-1075. Furthermore, we have to remember that in order to select the more suitable embryos for the uterine transference, they ordinarily apply invasive procedures such as biopsy, a method that harms the embryo. This article points out that removal a blastomere from an embryo of just six to eight cells, has an adverse effect in the development of the embryo. Cfr. UGAJIN T, TERADA Y, HASEGAWA H, ET AL. Aberrant behavior of mouse embryo development after blastomere biopsy as observed through time- lapse cinematography. Fertility and Sterility 2010; 93(8): 2723-2728. According to this other research study, the nervous system of the animals to which the preim- plantation genetic diagnosis is applied (PGD, method that implies the removal of blastomeres) may be sensitive to the removal of blastomeres, and it indicates the possibility of an increased risk of neurodegenerative diseases in such mice. Cfr. YU Y, WU J, ET AL. Evaluation of Blastomere Biopsy Using a Mouse Model Indi- cates the Potential High Risk of Neurodegenerative Disorders in the Offspring. Molecular & Cellular Proteomics 2009; 8: 1490-1500.
15 As it was mentioned above, through PGD abnormal embryos can be identified so that they are disposed. There are embryonic selection methods to implant the most suitable ones. According to this article, after applying PGD, out of the 7727 fertilized eggs, only 1206 babies were born. Cfr. HARPER JC, COONEN E, DE RYCKE M, ET AL. ESHRE PGD consortium data collection X: cycles from January to December 2007 with pregnancy follow-up to October 2008. Human Reproduc- tion 2010; 25(11): 2685-2707.
16 CONGREGATION FOR THE DOCTRINE OF THE FAITH. Instruction “Dignitas personae” (12.XII.2008), n. 19.
17 Cfr. BONET E, PARDO JM. Hay un embrión en mi nevera. El problema de los embriones congelados. Pamplona: Eunsa (Colección Astrolabio Ciencias); 2007. 18 Cfr. WILSON CL, FISHER JR, HAMMARBERG K, ET AL. Looking downstream: a review of the literature on physical and psychosocial health outcomes in adoles- cents and young adults who were conceived by ART. Human Reproduction 2011; 26: 1209-1219. This study analyzes medical literature in order to assess the pos- sible negative effects of assisted reproduction methods.
The review includes studies published between 1998 and 2010: seven of them describe the physical development of test tube babies, and ten the psychosomatic alterations.
19 Cfr. MCDONALD SD, HAN Z, MULLA S, ET AL. Preterm Birth and low Birth weight among in vitro fertilization singletons: a systematic review and meta-analyses. European Journal of Obstetrics & Gynecology and Reproductive Biology 2010; 148(2): 105-113; SAZONOVA A, KÄLLEN K, THURIN-KJELLBERG A, ET AL. Obstetric outcome after in vitro fertilization with single or double embryo trans- fer. Human Reproduction 2011; 26(2): 442-450; BEYDOUN HA, SICIGNANO N, BEYDOUN A. A cross-sectional evaluation of the first cohort of young adults con- ceived by in vitro fertilization in the United States. Fertility and Sterility 2010; 94(6): 2043-2049. This article points out that IVF is associated with some vascular disea- ses, depression and hyperactivity.
20 IVFET or ICSI babies run a higher risk of cerebral palsy. Cfr. ZHU JL, HVI- DTJORN D, BASSO O, ET AL. Parental infertility and cerebral palsy in children. Hum Reprod. 2010; 25: 3142-3145; the risk of cerebral palsy increases 1.9 times in in vitro babies when compared to the naturally conceived. Cfr. HVIDTJORN D, GROVE J, SCHENDEL D, ET AL. Multiplicity and early gestational age contribute to an increased risk of cerebral palsy from assisted conception: a population-ba- sed cohort study. Human Reproduction 2010; 25(8): 2115-23. In IVF babies, brain injury occurred more frequently than in the rest of population. Cfr. BELLIENI CV, BAGNOLI F, TEI M, ET AL. Increased risk of brain injury in IVF babies. Minerva Pediatr. 2011; 63(6): 445-448.
21 Although most of the children conceived in vitro have a normal development, an increase in neonate cases with Beckwith-Wiedemann syndrome (congenital growth disorder) and Angelman syndrome (neuro-genetic disorder characterized by intellectual and developmental delay) have been observed. Cfr. JOUVE N. Congenital Defects And Discapacity. Cuadernos de Bioética 2009; 3: 407-422, pp. 420-1.
22 Cfr. WISBORG K, INGERSLEV HJ, HENRIKSEN TB. IVF and stillbirth: a pros- pective followup study. Human Reproduction 2010; 25: 1312-1316.
23 Babies conceived by in vtro fertilization present and increasing cancer risk (he- mathological, ophtalmological, SNC and other kind of solid cancer), statistically significant, compared to babies conceived naturally. Cfr. KÄLLEN B, FINNSTRÖM O, LINDAM A, ET AL. Cancer Risk in Children and Young Adults Conceived by In Vitro Fertilization. Pediatrics 2010; 126(2): e270-e276; FINNSTRÖM O, KÄLLEN B, LINDAM A, ET AL. Maternal and Child outcome alter in vitro fertilization – a re- view of 25 years of population – based data from Sweden. Acta Obstet Gynecol Scand. 2011; 90: 494-500; VANNESTE E, VOET T, CAIGNEC C, ET AL. Chromo- some instability is common in human cleavage-stage embryos. Nature Medicine 2009; 15(5): 577-583; CHUNG A. Embryos donated for research likely have chro- mosomal abnormalities. Stem cells. Published online. 14 May 2009; doi:10.1038/ stemcells.2009.73.
24 “15 eggs is the perfect lumber to achieve a live Birth”. SUNKARA SK, RITTEN- BERG V, RAINE-FENNING N, ET AL. Association between the number of eggs and live birth in IVF treatment: an analysis of 400 135 treatment cycles. Human Reproduction 2011 DOI: 10.1093/humrep/der106.
25 Thromboembolism is the most serious complication of ovarian hyperstimulation syndrome. These thromboembolic accidents are very seldom compared to the high number of women that undergo IVF procedures; however these cases are so severe that it is worth it to take them into consideration. Therefore before starting any procedure it would be absolutely necessary to analyze if there is any risk fac- tor which predisposes the woman to suffer a thromboembolic accident. Cfr. JING Z, YANPING L. Middle cerebral artery thrombosis after IVF and ovarian hypersti- mulation: a case report. Fertility and Sterility 2011; 95(7): 2435.e13-2435.e15; BRAAT DDM, SCHUTTE JM, BERNARDUS RE, ET AL. Maternal death related to IVF in the Netherlands 1984–2008. Human Reproduction 2010; 25: 1782-1786. This article evaluates the side effects of ovarian hyperstimulation syndrome and maternal death related to IVF. Here it is clearly explained that the maternal death rate related to IVF procedures was comparatively higher than the maternal morta- lity rate in the general Dutch population.
26 30% of the couples that try IVF can not have a baby after three attempts. Cfr. MALIZIA BA, HACKER MR, PENZIAS AS. Cumulative Live-Birth Rates after In Vi- tro Fertilization. N Engl J Med. 2009; 360: 236-243. According to a research study by Swedish experts published in Human Reproduction, about 65% of the couples that abandon an assisted reproduction procedure without achieving a pregnancy, do it due to psychological tiredness rather than to medical or economic reasons. The feeling of loosing control over life itself, of being useless for not being able to conceive a child, of being at the mercy of a third party, the physicians, result in what is called “the syndrome of infertility”. The problem is that society does not prepare for infertility but rather for avoiding a pregnancy. There is a lot of precipita- tion in the use of IVF. It is necessary to teach women to get to know their own body, the periods of higher fertility. In addition, it is important to study the causes of infertility carefully, before starting an artificial human reproduction procedure.
27 In the United States, the percentage of twin or multiple pregnancies due to IVF is 35% and in Europe about 25%. In natural fertilization the percentage is only about 1%.
28 Cfr. BEWLEY S, FOO L, BRAUDE P. Adverse outcomes from IVF. BMJ. 2011; 342: d436 doi: 10.1136/bmj.d436 (Published 27 January 2011); KNOPMAN J, KREY L.C, LEE J, ET AL. Monozygotic twinning: an eight-year experience at a lar- ge IVF center. Fertility & sterility 2010; 94(2): 502-510; CHAUHAN SP, SCARDO JA, HAYES E, ET AL. Twins: prevalence, problems, and preterm births. American Journal of Obstetrics & Gynecology 2010; 203(4): 305-315.
29 The rest of the embryos, both the sick and the healthy, which are not immunolo- gically compatible with their already born brother are disposed.
30 Cfr. SPRIGGS M. Lesbian couple create a child who is deaf like them. J Med Ethics. 2002; 28: 283.
31 “Surrogate Maternity: a popular industry in India”, is the title of an article in Ace- prensa dated August 30th 2010. Today, reproductive tourism is even more promo- ted. India has become the main provider of surrogate maternity services because of its low costs, lack of regulation and its high quality standards in private hospi- tals. Hospitals in India (over 350) charge about 25,000 dollars for the service, whi- le in the United States (in the State of California for instance) it would cost about 100,000. In 2012, this industry will generate 1.5 billion euros, according to data provided by the India Industrial Confederation. The typical Indian surrogate mo- ther is a woman from the countryside of very low income. Frequently they are illite- rate women that ignore the risk this procedure carries and they charge about 100,000 rupiahs (3,120 dollars) per birth.
32 See:
33 A similar situation is observed with semen. In Cryos Denmark web, the largest sperm bank worldwide, half a liter of bottled spermatic fluid costs approximately 500 euros, and 50 milliliters cost 30 euros.
34 MARQUARDT E, GLENN N, CLARK K. My Daddy ́s Name is Donor. A New Stu- dy of Young Adults Conceived Through Sperm Donation (2010), at: http:// Studied on October 17, 2011.
35 This same anxiety is described in an article published in The New York Times on Septembrer 6, 2011. A social worker in the Washington area reveals that the semen used to conceive her son, seven years ago, has been used to conceive at least another 150 children. Some authors have warned about the possibility of ac- cidental incest amongst “siblings”.
36 Cfr. SIFFROI J.P, CHARRON P, BUJAN L. Heritable disease and sperm dona- tion. JAMA 2010; 303(7): 617-618.
37 MARON BJ, LESSER JR, SCHILLER NB, ET AL. Implications of Hypertrophic Cardiomyopathy Transmitted by Sperm Donation. JAMA 2009; 302(15): 1681- 1684.
38 Cfr. KOBAYASHI H, HIURA H, ET AL. DNA methylation errors at imprinted loci after assisted conception originate in the parental sperm. European Journal of Hu- man Genetics 2009; 17: 1582–1591.
39 SPAR DL. The baby business. How money, science, and politics drive the com- merce of conception. Boston: Harvard Business School Press; 2006.
40 Cfr. Law 14/2006 May 26, chapter II, artícle 5, n. 7. In Spain, the robot portrait of the donor is the one of a young university student no older than 33. The pay is about 600 euros.
41 Cfr. JADVA V, CASEY P, READINGS J, ET AL. A longitudinal Study of Recipients’views and experiences of intra-family egg donation. Human Reproduc- tion 2011; 26: 2777-2782.
42 LEVINE AD. Self-Regulation, Compensation, and the Ethical Recruitment of Oocyte Donors. Hasting Center Report 2010; 40(2): 25-36.
43 JOHN PAUL II. SAddress of the Holy Father to the members of the Pontifical Academy for Life. (March 3, 2001), n. 3.