A natural-cycle IVF does not involve ovarian stimulation. Instead, we collect the one egg that you normally release in your menstrual cycle and fertilize it with sperm in vitro (in a dish), and if successful, we transfer it back in your womb. Some hormonal support may be required around the egg collection time, or during the second half of your menstrual cycle (luteal phase) when implantation may occur, but no other fertility drugs are used in a natural cycle of IVF.
IVF-natural cycle can benefit women that have a low ovarian reserve (low capacity of producing eggs). In some cases, patients with low ovarian reserve have only one ovarian sac, or follicle, for egg production. So, despite ovarian stimulation only one egg can be produced due to the lack of follicles.
Further, it is recommended to women that are unable to take fertility drugs. For instance, women who may have overcome a form of cancer.
Additionally, IVF-natural cycle is recommended to couples, who object to have an excess of eggs stored or potentially destroyed.
An IVF-natural cycle is the same as an IVF cycle without the fertility drugs that increase ovarian stimulation. We monitor the production of the egg and progression of its maturation with ultrasound transvaginal scans. Hormone levels may also be checked through a blood test.
Egg collection: With minimal hormone support (just injection of the human chronic gonadotropin (hCG), for egg final maturation), we adjust the timing of the ovulation and schedule the egg collection.
This is performed by a doctor, with the use of a fine, hollow needle using ultrasound guidance and conscious sedation for prevention of any discomfort. Unlike IVF, none or only a short recovery time may be required, after which you can return to your daily activities as normal.
Fertilization and embryo transfer: After the first day of combining your egg and the sperm in a dish, the embryologist performs a microscopic examination to check whether fertilization has occurred. If an early embryo is detected, it will be monitored (conventional microscopy / EmbryoScope® time-lapse imaging system) up to the stage of 2-3-day embryo, or up to the blastocyst stage, depending on your individual circumstances, and then transferred in your womb.
Embryo transfer is performed by a doctor, under ultrasound guidance and the use of a fine tube (catheter) that delivers the embryo back into the womb. It is normally a pain-free step that takes about 5 minutes to complete without the need for anesthesia or recovery time.
The risks with an IVF-natural cycle are much lower, as any side effects from fertility drugs, and the chance of conceiving duplets or triplets are avoided.
Pregnancy test and first pregnancy scan: Approximately, after 14 days of embryo transfer a pregnancy test checking whether your IVF-natural cycle has been successful will be performed. A positive outcome will be followed up by an ultrasound transvaginal scan, performed by one of our specialists.
IVF-natural cycle is not a first-choice assisted reproductive technique, as it has a very low rate of success. With this method, your ability to become pregnant is not artificially enhanced (by fertility drugs), and therefore its success relies entirely on your individual circumstances.
In 80% of the cases, we are able to collect the egg, but in 20% of patients there is no egg after egg collection. Fertilization normally happens in around 80% of the collected eggs. Further, from the fertilized eggs, around 20% of them become arrested during one of the cleavage stages. So, at the end, women that have one embryo that progressed normally and transferred to their womb may become pregnant, but this will also depend on their age, medical and fertility history.
Overall, an IVF-natural cycle provides a success rate of approximately 5-10% per attempt.