Natural Cycle IVF/ IVF Treatment Process

In women having regular periods, the ovaries produce an egg every month. Natural cycle IVF is a type of IVF treatment whereby we aim to retrieve the egg that one’s body has selected. Thus, no ovarian stimulating drugs are used unlike the conventional IVF treatment. At CRGH it is usually used for women where medication is either unlikely to help in recruiting a higher number of eggs (clinically known as a ‘suboptimal ovarian reserve’ or those with a previous suboptimal response to ovarian stimulation ‘poor responders’). In standard IVF, fertility drugs are given to stimulate the production of multiple eggs. Natural cycle IVF is a patient friendly treatment, as no fertility drugs are given.

As natural cycle IVF follows the normal menstrual cycle, usually only one egg is obtained. The entire process takes 15 days during which time the woman is monitored to track the development of her follicles, using ultrasound scans and blood tests. There is quite a high cancellation rate (approximately 30%) due to either high hormonal levels at the start of a cycle, arrest in follicular growth or premature ovulation. The egg collection is usually done using sedation. Ultrasound guided follicular aspiration is done. In the aspirate of the follicle, the embryologist should be able to identify the egg. The egg is then placed in culture media in our laboratory.

The embryologists will prepare the sperm for insemination. If the sperm quality is good, the sperm will simply be mixed with the egg and fertilization will hopefully happen. If the sperm quality is poor, then ICSI may be performed. The following day the embryologists will look for signs of fertilization (day 1 after the egg collection). The next day they will check to see if the embryo has cleaved (day 2 after the egg collection). The embryo is subsequently frozen on day-3. In women with poor ovarian reserve or previous suboptimal response, we will advise women to embark on multiple cycles to pool day-three embryos. Our embryologist will then thaw and grow all day-3 embryos to blastocyst for subsequent frozen embryo transfer.

If you would like to book an appointment with one of our doctors you can:

  • Speak to the booking team on +44 (0)20 7837 2905  (Mon – Fri 8.30am – 6pm)
  • Email us on 
  • Visit our Appointments page, fill out the contact form and a member of the team will be in touch

IVF Packages With Access Fertility

IVF Packages With Access Fertility
CRGH is partnering with Access Fertility to offer a series of IVF programmes and packages. For more information please click below.

NHS Funding for Fertility Care

CRGH is an NHS approved centre and funding may be available for some patients. You will need to meet certain criteria and be referred to us by your GP. Please call or email us for further information.
Call: +44 (0)20 7837 2905

or click below:

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