Second IVF cycle: what to consider before trying again
When a first in vitro fertilisation (IVF) treatment does not result in a pregnancy, it can raise many questions: why didn’t it work? Does the treatment need to change? How long should we wait? Are the chances better in a second attempt?
Receiving a negative result after all the hope placed in the treatment is a difficult moment for any couple, and it is natural to feel sadness, frustration or exhaustion. However, a negative result does not necessarily mean that there is a problem preventing a pregnancy. IVF does not guarantee success in every cycle, and the outcome depends on many factors, including age, ovarian reserve, response to stimulation, fertilisation and the male factor, embryo development and the condition of the uterus and endometrium.
That is why a second treatment should not simply be approached as a repeat of the first. A detailed review of the previous cycle makes it possible to identify what happened and decide whether the strategy needs to change.
Is it normal for a first IVF attempt to fail?
Yes. A first IVF cycle may not achieve a pregnancy even when there is no obvious problem.
It is important to distinguish between the outcome of a specific cycle and the overall reproductive prognosis of a patient or couple. In each IVF cycle we aim to significantly increase the chances of achieving a pregnancy, but current success rates are far from 100%. In addition, these success rates can be expressed in different ways: per cycle, per transfer or cumulatively, taking into account transfers of vitrified embryos. For this reason, the figures should always be interpreted in context and not as an individual prediction.
A first IVF cycle that did not work should not be seen as a personal failure or as a wasted step. What matters is to analyse the treatment and use the information obtained to plan the next step. The fertility assessment carried out beforehand gives us partial information about the patients’ baseline situation, but once we have the opportunity to see how the eggs and sperm behave in vitro, we learn much more about the real situation.
Analysing the first attempt
Before starting a second IVF cycle, it is essential to review the whole previous cycle in detail.
Response to ovarian stimulation
We analyse how the ovaries responded, how many follicles developed, how many eggs were retrieved and how many were mature.
This information makes it possible to assess whether the protocol and doses used were appropriate, or whether some adjustment may be advisable in a new cycle. The aim is not always to obtain as many eggs as possible, but to achieve a response suited to each patient’s characteristics.
Fertilisation and embryo development
We also need to know how many eggs were fertilised correctly and how the embryos developed.
A low fertilisation rate or no fertilisation at all may make it necessary to review the male factor and the fertilisation technique used. Similarly, if embryo development arrests, it is important to assess the characteristics of the eggs, the semen and the embryos together.
Endometrial receptivity and implantation
If good embryos were obtained but the transfer did not result in a pregnancy, the characteristics of the uterus and endometrium and the patient’s medical history are reviewed.
However, not all endometrial receptivity tests are indicated routinely. Current evidence recommends using them on an individual basis and avoiding the assumption that implantation failure is necessarily due to a receptivity problem.
Failed implantation versus biochemical or clinical miscarriage
It is also important to know at what point the failure occurred.
Not achieving a pregnancy after the transfer is not the same as getting an initial positive test and then losing the pregnancy. A biochemical pregnancy involves an initial rise in beta-hCG with no ultrasound evidence of an ongoing pregnancy, whereas a clinical miscarriage is diagnosed when the pregnancy has been seen on ultrasound.
This information can guide the assessment before a new treatment in different ways, especially when considering a second IVF cycle after a miscarriage.
Recommended time between IVF treatments
There is no universal waiting period before a second IVF cycle.
The right time depends on the patient’s physical and emotional recovery, the treatment carried out and whether vitrified embryos are available.
When suitable vitrified embryos are available, a second IVF attempt with frozen embryos can be considered, with the transfer carried out in a later cycle without repeating ovarian stimulation and egg retrieval. If new stimulation is needed, the specialist will decide when it is best to start, depending on individual circumstances.
Therefore, waiting longer does not necessarily mean a higher chance of success. The time between treatments should be used to recover, review the previous cycle and design the most suitable strategy.
Chances of pregnancy in a second IVF cycle
When assessing the chances of success of a second IVF cycle, it is worth bearing in mind that the second attempt has an advantage over the first: we have real information about how the patient responded to treatment.
We know how her ovaries responded, how many eggs were obtained, how they fertilised and how the embryos developed. This data allows a more accurate assessment and, where indicated, a change of strategy.
Cumulative rates: first, second and third attempt
When assessing the chances of IVF, it is particularly useful to talk about cumulative rates, because a single stimulation can produce several embryos and therefore several transfer opportunities, and can even make it possible to try for a second pregnancy through IVF later on without the need for new stimulation.
Rates vary considerably depending on age, diagnosis and each patient’s characteristics. For this reason, general statistics should be used to put expectations into context, but they cannot predict the outcome for an individual patient.
Factors that influence the outcome of the second attempt
The main factors include:
- Age and ovarian reserve.
- Response to stimulation.
- The number and maturity of the eggs obtained.
- The fertilisation rate.
- Embryo development and characteristics.
- The male factor.
- The condition of the uterus and endometrium.
- A history of pregnancy or miscarriage.
- The availability of vitrified embryos.
What can change compared with the first cycle
The aim of a second IVF cycle is not necessarily to add more treatments or tests, but to identify which aspects can be optimised on an individual basis.
Adjustments to the stimulation protocol
Depending on the response in the first cycle, the medication doses, the stimulation protocol or certain timings in the treatment can be modified.
The strategy should be adapted to ovarian reserve, age and the response previously observed.
Complementary laboratory techniques
ICSI may be particularly indicated when there is a significant male factor or when there was low or failed fertilisation in a previous treatment using conventional IVF.
Blastocyst culture makes it possible to select the embryos that reach an advanced stage of development before they are transferred or vitrified.
PGT-A, for its part, makes it possible to analyse certain chromosomal abnormalities in embryos and may be useful in selected patients, depending on age, medical history and the characteristics of the treatment.
Habits and self-care before starting again
Before a second IVF cycle, it is advisable to maintain healthy habits: avoid tobacco, limit alcohol, exercise and eat a balanced diet.
It is also a good idea to review any regular medication and take folic acid before pregnancy, following the specialist’s recommendations.
These habits contribute to reproductive and general health, but we must not forget that neither infertility nor the outcome of treatment depends solely on the patient’s lifestyle.
The emotional side: preparing for a second attempt
A second treatment can bring fear, anxiety or emotional exhaustion, especially when the first cycle was experienced very intensely.
Professional support can help to manage uncertainty and expectations. Psychological support specialising in assisted reproduction can be part of the treatment and help the patient face the new cycle with greater confidence.
How we support a second IVF attempt at Instituto Bernabeu
At Instituto Bernabeu, we see the second treatment as an opportunity to learn from the previous cycle and personalise the reproductive strategy even further.
Together with the patients, we will once again review their clinical and reproductive history, the protocol used, the ovarian response, fertilisation, embryo development and the outcome of the transfer. Based on this information, an individualised plan is designed, avoiding any tests or techniques that do not offer a real benefit in each case.
Our multidisciplinary approach brings together the expertise of specialists in reproductive medicine, endocrinology, immunology, embryology, genetics and emotional support for infertility.
In addition, Instituto Bernabeu offers pregnancy guarantee programmes such as ÚNICA Bernabeu, aimed at certain patient profiles and subject to specific medical criteria.
The shared goal is not just a positive pregnancy test, but an ongoing pregnancy and the birth of a healthy baby.
Frequently asked questions
How many IVF attempts can you have?
There is no maximum number of attempts that is right for every patient. The decision to continue should be made on an individual basis, taking into account age, ovarian reserve, the response to previous treatments, the embryos obtained, medical history and reproductive prognosis.
After each treatment, and especially after a second negative IVF cycle, it is advisable to reassess the situation and decide whether it makes sense to continue, change the strategy or consider other alternatives.
How long should you wait before a second IVF cycle?
There is no mandatory waiting period for all women. If the patient has recovered and there are no medical reasons to delay treatment, new stimulation may even be considered in the following cycle.
When vitrified embryos are available, it may also be possible to carry out a transfer in a later cycle without repeating stimulation.
In short, a second in vitro fertilisation cycle does not have to be a repeat of the first. Analysing what happened during the first treatment makes it possible to take more informed decisions and adapt the strategy to each patient’s current circumstances.
What are the chances of getting pregnant in a second IVF cycle?
The fact that a first in vitro fertilisation (IVF) treatment did not result in a pregnancy does not mean that the next attempt will fail. It is important to bear in mind the concept of the cumulative pregnancy rate: the chances of achieving a pregnancy increase as more embryo transfers are carried out. Having a larger number of embryos therefore provides more opportunities for success.
Once again, the specific chances will depend on each case, and the information obtained during the first cycle should be analysed and used to optimise subsequent treatments.
Dr Esperanza de la Torre, gynaecologist at Instituto Bernabeu Madrid