Next Fertility IVF Prof. Zech

Success Rate

Success Rate - Backgrounds
and Meaning

About one in five couples today are involuntarily childless, and the need for professional medical support is increasing. When looking for a suitable IVF center, the Internet provides numerous possibilities to gain detailed information beforehand on the varied choices offered by the IVF center in question, including the treatment procedure, the specialists responsible for the realization of the therapy etc. However, for many people concerned, it is even more important to know what the performance figures of a clinic look like (e.g. pregnancy rate, birth rate):

Pregnancy rate - Next Fertility IVF Prof. Zech

Number of women who got pregnant after an IVF attempt (therapy cycle) (all age groups, transfer of top blastocysts):
Pregnancy rate following Beta-hCG testing, non-cumulative, transfers involving at least one top blastocyst (AA, BA or AB), analyzed time period: 1 January 2014 - 31 December 2016 (3 years) at Next Fertility IVF Prof. Zech Bregenz │ © 2022 Next Fertility IVF Prof. Zech • Member of Nextclinics

Number of women who got pregnant after an IVF attempt (therapy cycle) (up to 37 years of age, all transfers)
Pregnancy rate following Beta-hCG testing (clinical pregnancy rate about 2% lower in each case), non-cumulative, all transfers, analyzed time period: 1 January 2014 - 31 December 2016 (3 years) at Next Fertility IVF Prof. Zech Bregenz │ © 2022 Next Fertility IVF Prof. Zech • Member of Next Clinics

In some countries, IVF clinics are required by law to publish their results. In countries where there is no such legal obligation, the provision of these data takes place on a voluntary basis. We are continually faced with cases, where partly pregnancy rates of over 90% are reported which are often even accompanied by a message stating that the pregnancy rate allows an informed assessment of the likelihood of successful fertility treatment. Hence, we at our IVF centers clearly dissociate ourselves from such promises. There is no such thing as the "one and only" success parameter.

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Success rate

"... and what does that mean for us?"

In light of past experience, this is a question in which many couples are interested when looking at the outcomes presented. In order to be able to give a useful answer to that question, it is important, firstly, to understand that the underlying reason for infertility mostly consists of a combination of factors, such as diseases, genetic disorders, age-related factors, unhealthy lifestyle habits, harmful environmental influences. The chances of a successful treatment outcome are based primarily on the personal situation of the patients. With regard to the treatment results published by an IVF center, it is to be noted that such results do not apply to all affected women/men equally (e.g. indication of age group and pregnancy rate) and should therefore be viewed on a differentiated basis. The following is a case example.

Pregnancy and birth

A pregnancy can be confirmed by biochemical tests (detection of the pregnancy hormone human chorionic gonadotropin (hCG) in the blood) or by visual examination (using ultrasound technology, e.g. presence of fetal heartbeat). The "visual confirmation" of a pregnancy is referred to as clinical pregnancy (rate). This is, of course, what we desire, but unfortunately not all positive pregnancy tests will lead to a vital pregnancy resulting in the birth of a child (live birth rate). Therefore, the clinical pregnancy rate is always considered to be the more reliable parameter.

Depending on the course of pregnancy, the live birth rate may differ from the initially stated pregnancy rate. │ © 2022 Next Fertility IVF Prof. Zech • Member of Next Clinics

Cumulative or non-cumulative

The term "cumulative" derives from the Latin word "cumulare" (to accumulate). The cumulative pregnancy rates are calculated by taking into account the number of pregnancies achieved in the context of medically assisted reproduction after several consecutive embryo transfers ("fresh" and "frozen" cycles) and indicates that the likelihood of becoming pregnant increases with the number of IVF attempts the patient has already undergone.

Although the chances of success per attempted treatment (therapy cycle) remain the same (e.g. 47%), the prospect of success calculated on a cumulative basis increases with each additional attempt. Depending on the method of calculation, there might be considerable differences between cumulative and non-cumulative results. │ © 2022 Next Fertility IVF Prof. Zech • Member of Next Clinics

The cumulative pregnancy rate can be calculated in different ways, but it is difficult to be quantified and may give rise to false estimations. For example, there is no consensus on the number of attempts that shall be taken into account for the cumulative calculation. Each fertility treatment is to be seen as an "independent event", i.e. the outcome (whether positive or negative) of a previous therapy does not have any impact on a possible further treatment. It's like rolling the dice. The probability of rolling a six is 1:6. If after 5 tries a 6 has not been rolled, the sixth try offers exactly the same odds as the previous attempts, that is to say 1:6.

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Success rate

Using customized therapies to increase the probability of pregnancy

However, there is no guarantee that the fertility treatment will be successful. However, thanks to intensive research in the field of reproductive medicine and the development of new procedures, the prospects of success are notably higher today than just a decade ago. As a fundamental rule, evaluating the chances of fertility treatment success always requires a customized approach, i.e. taking into account the couple's medical and personal circumstances. This is even more important in view of the fact that the chances of becoming pregnant might be influenced by a variety of factors. The following list shows a choice of aspects that are decisive for us when it comes to a realistic assessment of each individual couple's chances of getting pregnant:

  • Age of the woman
  • Type and length of the infertility
  • Possible pre-existing conditions
  • Genetic constitution of the couples (balanced translocations, genetic diseases etc.)
  • Ovarian reserve
  • Quality of the gametes (oocytes and sperm)
  • Quality of the transferred blastocyst(s)
  • IVF treatment using own oocytes/sperm or donated oocytes/sperm
  • Selection of the stimulation protocol
  • Case history (anamnesis)
  • Risk factors
  • Response to previous stimulations
  • BMI (Body Mass Index)
  • Antral Follicle Count (AFC)
  • Hormonal status
  • AMH levels etc.

Against this background, our medical approach is based on therapies that are tailored to the individual needs of the patients, including detailed analyses and mechanisms of selection carried out by a team of specialized physicians, biologists, and geneticists (Learn more).

In order to help you realize your dream of having a child, the following aspects are of utmost importance to us. The focus rests on the couple´s individual medical situation combined with the means at our disposal and our professional performance.