Associated Risks

PMA, like any other medical technique or human activity, has its own risks

Multiple pregnancies

Multiple pregnancies are significantly correlated with higher rates of premature babies and low weight babies (less than 1500g). A study performed in England (UK Triplet study, 1990) showed 0.7% of babies were weighing less than 1500g in single pregnancies compared to 9% in twins, 28.4% in triplets and 52.3% in quadruplets.

Complications amongst the newborn are more important in number and in severity in case of twin and triplet pregnancies. In Western Australia, between 1980 and 1989, the frequency of cerebral paralysis was 1/1000 with single children, 9/1000 with twins and 25/1000 with triplets.

Costs in relation to multiple pregnancies are extremely high.

The IVF treatment allows an easy control of these problems by limiting the number of embryo transferred to 2 or even to 1. Indeed, a transfer of 3 embryos has no longer any justification in the actual IVF treatment. In some IVF Centres, pregnancy rates reached after transfers of frozen-thawed embryos are almost similar to those obtained after transfers of fresh ones.

Les grossesses multiples sont significativement associées à un taux de prématurité plus élevé et à la naissance d’enfants de faible poids (moins de 1'500 gr). Une étude anglaise (UK Triplet study, 1990) a montré 0.7% d’enfants de moins de 1'500 gr chez les grossesses uniques, 9% chez les jumeaux, 28.4% chez les triplés et 52.3% chez les quadruplés.

Les complications chez l’enfant né sont aussi plus importantes en nombre et en sévérité chez des enfants issus de grossesses gémellaires et à fortiori triples ou plus. En Australie de l’ouest, la prévalence de la paralysie cérébrale entre 1980 et 1989 était de 1/1000 chez les enfants uniques, de 9/1000 pour les jumeaux et de 25/1000 pour les triplés.

Les coûts inhérents aux grossesses multiples sont de même extrêmement élevés. La fécondation in vitro permet de gérer beaucoup plus aisément ce problème par la limitation du nombre d’embryons transférés à 2, voire à 1. En effet, un transfert électif de 3 embryons n’a actuellement plus sa place dans les traitements de FIV modernes. Les taux de grossesse obtenus après transfert d’embryons congelés-décongelés sont voisins dans certains centres de ceux recensés après transfert d’embryons frais.

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Ovarian hyper stimulation syndrome (OHSS)

The ovarian hyper stimulation syndrome is the most frequent complication encountered in IVF (1-5%). OHSS is a very high ovarian response to the stimulation, which is not predictable and can vary in the level of severity. The use of GnRH analogy increases the risks and the pregnancy intensifies the severity of the syndrome. Sometimes, the doctor has to stop the treatment, either during the course of the stimulation protocol, either after the oocyte pick-up as soon as the hyper stimulation has been diagnosed (all the zygotes are then cryopreserved and the fresh transfer is cancelled). The transfers of frozen-thawed embryos will take place during further natural or artificial cycles.

Beyond the disappointment due to the fresh transfer cancellation, OHSS can be life threatening. It must be detected and treated rapidly. In rare cases, hospitalisation is required, for clinical and biochemical monitoring. The treatment consists in preserving renal function with drugs or in aspirating ascetic fluid from the abdomen by inserting a drainage-tube.

Collaboration between the doctor and the patient is essential in this context and the symptoms of HOSS, such as abdominal distension, nauseas, a decrease in urine production must be announced imperatively to the UMR.

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Ectopic pregnancy

Ectopic pregnancy (GEU) occurs when the pregnancy implants outside the womb. This type of pregnancy is one of the most complicated of IVF and concerns 1-5% of the pregnancies obtained with these treatments. Although the embryos are replaced inside the uterine cavity, they are able to migrate back in the fallopian tube with the help of the natural uterine contractions.

When pregnancy occurs, the blood tests give some information on the embryo evolution and a scan, performed one month after the transfer, allows localizing the foetal sac.

When an ectopic pregnancy is detected, it is usually necessary to perform a laparoscopy, a surgical procedure to remove the foetal sac from the fallopian tube. Sometimes, removal of the entire fallopian tube is inevitable. In some particular cases, a medical treatment (Methotrexate) can be given to the patient in order to stop the evolution of the pregnancy.

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Malformations

Over a million children have been born in the world with the help of an IVF or ICSI treatment. The epidemiological data on health and development of these children are very reassuring. However, our Centre, likewise other Centres, does a follow-up of the children and their development by means of phone calls and personalized questionnaires.

So far, the number of observed malformations among children born after IVF and ICSI treatments is slightly higher (5.3%) than for the general population (3-4%).

In our Centre, amongst the 737 children born after IVF, 19 (2.5%) of them presented a severe malformation and 15 (2.0%) a mild malformation. Under the 589 children born after ICSI, 10 (1.7%) presented a major malformation and 21 (3.6%) a minor one.

The congenital malformations do not seem to be directly correlated to the techniques used, IVF or ICSI. The origin of these malformations is most of the time attributed to hereditary genetic factors or maternal causes.

Children presenting a malformation after IVF treatment are more likely to present cardiac abnormalities, while the children born after ICSI show more uro-genital problems.

The chromosomal malformations such as Trisomy 21 (Down syndrome) can be detected by performing a blood test and an early scan (12 weeks of pregnancy), or by a specific blood test (What If) between weeks 16 and 18 of pregnancy, or by amniocentesis.

Other malformations are detected by ultrasound scan. Depending on the severity of the malformation, a therapeutic pregnancy termination has to be considered.

Therefore, prenatal diagnosis and genetic counselling are strongly recommended.

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Other risks

Other risks, although extremely rare or close to non-existent, should be mentioned:

• ·Traumatic or infectious risks secondary to OPU or to transfer (<0.1%)
• ·Culture medium contamination (sperm infection, unintentional contamination during the oocyte pick-up or in the laboratory) (<0.1%)
• ·Gametes or embryo exchanges in the laboratory or at the time of transfer. Everything has been implemented so that such risks would be reduced to zero by the use of multiple controls and a tractability of each step of every procedure.
• ·Risks of uterus, ovary or breast cancers, secondary to ovarian stimulation. No study so far has confirmed those risks.

The risk of a genetic transmission of the paternal sterility-infertility to the male lineage is to be considered with the ICSI and FIV procedures when the hypo-spermatogenesis is due to the Y-chromosome mutation. However, this risk also exists with a natural conception.

The psychological tiredness following repeated failures of the treatments or a difficult financial situation impeding access to the treatments are risks for the couples that are not directly linked to the treatment or to the technique used.

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