Kosmogonia IVF

Μultiple pregnancy and IVF

Why higher in IVF?

What to expect?

The risks

Why higher in IVF?
In IVF several embryos are transferred because not every embryo has the potential to develop, implant and produce a pregnancy. As many a 3 or 4 embryos are routinely transferred in Greece.

USA Results for 2001
Using ART, what is the risk of having a multiple-fetus pregnancy or multiple-infant birth?

26,550 pregnancies that resulted from ART cycles using fresh nondonor eggs or embryos, 58% were singleton pregnancies, 29% were twin pregnancies, and about 7% were triplet or greater pregnancies. About 5% of pregnancies ended in miscarriage in which the number of fetuses could not be accurately determined. Therefore, the percentage of pregnancies with more than one fetus might have been higher than the 37% reported.

From 21,813 live births There was 64.2% singleton birth. The total multiple-infant live births was 35.8% ( which are subdivided as follows: Twins 32.0% ,Triplets or more 3.8%).

While avoiding selective reduction of a fetal sac the couple would have to decide what to do with left over “spare” embryos that they do not want implanted.
With single embryo transfer, patients may feel pressured to choose the genetically “perfect” embryo. Will parents who make such a choice be more likely to view their children as commodities?

Personal communication with colleagues in the UK have confided that the overall success rate of their centers has fallen slightly due to the pressure from the HFEA to reduce multiple pregnancies and a almost total ban on transferring more than two embryos.

A recent study has shown that if single embryo transfer if combined with the success rate after frozen thaw embryo transfer the success is the same as transferring 2 embryos.

Success and single embryo transfer in IVF
First study to show that when counting frozen as well as fresh embryos, single embryo transfer does not reduce the chances of having a baby
Doctors in Australia have found that transferring one embryo instead of two during an IVF cycle does not reduce the chances of a woman having a baby, when frozen as well as fresh embryos are taken into account.
Dr. Jim Catt, Embryology director of Sydney IVF, Australia, and his colleagues have conducted the first study looking at cumulative pregnancy and live birth rates that took into account the transfer of previously frozen as well as fresh embryos. In 382 IVF patients aged under 38, who had at least two five-day-old embryos that were suitable for transfer or freezing, the cumulative live birth rate was exactly the same whether one or two embryos had been transferred in the first cycle.

Women who chose to have two embryos transferred in one cycle had a higher chance of success first time round – their live birth rate was 50% as opposed to 36% among the women who chose to have a single embryo transferred.

But when the previously frozen embryos were subsequently transferred to the women who had failed to become pregnant in the first cycle, the cumulative live birth rates for both groups of women was the same.

Dr. Catt said: "This is the first time that a study of cumulative pregnancy and live birth rates with five-day-old SET embryos has been conducted. Under the conditions of this study, twin pregnancies can be reduced drastically without compromising a patient's chance of a successful pregnancy.

A important point to remember though is that… for this particular study “all patients were younger than 38 in order to avoid complicating the analysis with the well known effect of age on pregnancy rates”.

All patients younger than 38 are now offered SET and approximately 70% of them accept, with an acceptable ongoing pregnancy rate of 40%.

Although the total rates for multiples were similar between pregnancies and live births, there were more triplet pregnancies than triplet births. Triplet (or more) pregnancies may be reduced to twins or singletons by the time of birth. This can happen naturally (e.g., fetal death), or a woman and her doctor may decide to reduce the number of fetuses using a procedure called multifetal pregnancy reduction.

Single embryo transfer
The delivery of a single, healthy child is the desired outcome of human assisted reproduction techniques. To attain this goal, there is an increasing movement to single embryo transfer.
Multiple-infant births are associated with greater problems for both mothers and infants, including higher rates of caesarean section, prematurity, low birth weight, and infant disability or death.
In any given cycle of treatment the probability of conceiving a child will be further increased by the ability to cryopreserve those embryos not transferred. It has therefore been proposed that the transfer of a single embryo is the future treatment for many patients.

The bigger picture
The trend towards single embryo transfer started in Scandinavian countries where several ivf attempts are sponsored by the state. It is less appealing to paying couples in a private health care system where the cost of future ivf attempts may be a difficulty.

In IVF several embryos are transferred because not every embryo has the potential to develop, implant and produce a pregnancy. As many a 3 or 4 embryos are routinely transferred in Greece.

Generally, due to there higher implantation capacity fewer embryos at the blastocyst stage are transferred reducing the problem of multiple pregnancies.

The chance of multiple pregnancy and the number of embryos transferred is usually assessed by mainly the maternal age of the women; other conciderations are embryo quality, type of fertility, number of previous attempts with low order transfers.

Despite the benefits of eliminating some of the risks associated with multiple pregnancy, the move to single embryo transfer is still questionable

Indeed, this procedure poses its own unique set of moral problems.
While avoiding selective reduction of a fetal sac the couple would have to decide what to do with left over “spare” embryos that they do not want implanted.
With single embryo transfer, patients may feel pressured to choose the genetically “perfect” embryo. Will parents who make such a choice be more likely to view their children as commodities?

Personal communication with colleagues in the UK have confided that the overall success rate of their centers has fallen slightly due to the pressure from the HFEA to reduce multiple pregnancies and a almost total ban on transferring more than two embryos.

A recent study has shown that if single embryo transfer if combined with the success rate after frozen thaw embryo transfer the success is the same as transferring 2 embryos.

Success and single embryo transfer in IVF
First study to show that when counting frozen as well as fresh embryos, single embryo transfer does not reduce the chances of having a baby
Doctors in Australia have found that transferring one embryo instead of two during an IVF cycle does not reduce the chances of a woman having a baby, when frozen as well as fresh embryos are taken into account.
Dr. Jim Catt, Embryology director of Sydney IVF, Australia, and his colleagues have conducted the first study looking at cumulative pregnancy and live birth rates that took into account the transfer of previously frozen as well as fresh embryos. In 382 IVF patients aged under 38, who had at least two five-day-old embryos that were suitable for transfer or freezing, the cumulative live birth rate was exactly the same whether one or two embryos had been transferred in the first cycle.
Women who chose to have two embryos transferred in one cycle had a higher chance of success first time round – their live birth rate was 50% as opposed to 36% among the women who chose to have a single embryo transferred.

But when the previously frozen embryos were subsequently transferred to the women who had failed to become pregnant in the first cycle, the cumulative live birth rates for both groups of women was the same.

Dr. Catt said: "This is the first time that a study of cumulative pregnancy and live birth rates with five-day-old SET embryos has been conducted. Under the conditions of this study, twin pregnancies can be reduced drastically without compromising a patient's chance of a successful pregnancy.

A important point to remember though is that… for this particular study “all patients were younger than 38 in order to avoid complicating the analysis with the well known effect of age on pregnancy rates”.
All patients younger than 38 are now offered SET and approximately 70% of them accept, with an acceptable ongoing pregnancy rate of 40%.


What to expect?
When do you find out you are expecting twins or more?
The value of the B-HCG blood test to determine if you are pregnant may give an indication if it is a multiple pregnancy. The values of a twin pregnancy can be elevated according to the number of fetal sacs.
The confirmation of a multiple pregnancy is seen 2-3 weeks later with an ultrasound scan where the number of sacs can be visualized and fetal heart activity monitered.


Risks
While couples in infertility treatment may conceive successfully, they face a higher than normal chance of multiple pregnancy, which carries with it significant risks such as Miscarriage, High Blood Pressure, Gestational Diabetes and Prenatal Mortality.
Also the chances of Low Birth Weight, Extended Hospitalization and Caesarian Delivery, Infant Mortality are higher in this group.