By Dra. Paloma Baviera (Gynaecologist – Reg. No. 030310335).
A poor response is considered when, despite appropriate hormonal medication and monitoring, the number of follicles or oocytes obtained is lower than expected. At IVF-Life, it is generally defined as the retrieval of three or fewer oocytes in a conventional cycle.
It is important to distinguish poor ovarian response from diminished ovarian reserve. Ovarian reserve refers to the approximate number of eggs available in the ovaries, whereas ovarian response reflects how the ovaries react to medication during a specific cycle. A woman may have diminished ovarian reserve but respond better than expected, or have an adequate reserve and still retrieve few oocytes after stimulation.
Ovarian stimulation is one of the first steps in an assisted reproduction treatment and one of the most important when using a patient's own eggs. Its aim is to promote the simultaneous development of several follicles in order to obtain mature oocytes that can be used in techniques such as in vitro fertilisation (IVF).
Sometimes the response to stimulation is not as expected. This results in a lower number of oocytes retrieved, but it does not necessarily mean that the treatment has failed or that pregnancy cannot be achieved.
Poor ovarian response can occur for a number of physiological, medical and individual reasons. The most common include:
Before treatment begins, several markers can help estimate the expected response and individualise the stimulation protocol:

There is no single solution suitable for every patient. The most appropriate approach depends on the woman's age, previous treatment outcomes, ovarian reserve, embryo quality and reproductive goals. Some of the most commonly used alternatives are:
Strategies according to patient profile:
Strategy | Common Indications | Advantages | Considerations |
Protocol adjustment | Suboptimal response in a previous cycle | May improve the number of oocytes retrieved | Depends on individual sensitivity |
Oocyte accumulation | Patients with consistently poor response | Increases the total number of oocytes available | Requires multiple cycles and planning |
Dual stimulation | Patients with limited time or advanced maternal age | Increases the number of oocytes within a single menstrual cycle | Requires closer medical monitoring and follow-up |
Natural IVF / Minimal stimulation | Poor response despite high medication doses | Lower hormonal exposure | Fewer oocytes retrieved per cycle |
Egg donation | Repeated failures or severe poor response | High chance of achieving pregnancy | Requires acceptance of donor eggs |
Not necessarily. A poor response reduces the number of available oocytes, but it does not by itself determine the success of treatment. Even a small number of oocytes may be enough to obtain good-quality embryos and achieve pregnancy.
Each cycle provides valuable information about how the ovaries respond, allowing the medical team to adjust strategies to maximise the chances of success. The goal is not always to retrieve a large number of oocytes, but rather those with the greatest reproductive potential through individualised monitoring and a treatment plan tailored to each patient.
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