Six Facts to Know When Thinking of Natural IVF

One in seven couples will seek help when having difficulties getting pregnant. Many of these will have to consider different forms of Infertility treatments.

Infertility treatments include:

  • artificial Insemination or IUI;
  • in vitro fertilisation or IVF;
  • Intracytoplasmic sperm insemination or ICSI;
  • IVF with donor eggs and/or donor sperms.

Most of the treatments involve the use of some form of fertility drug. Some patients who take these drugs experience side effects. Hence, some women consider the option of natural IVF or Natural cycle IVF.

It is important that you understand why natural IVF may be a better option than the stimulated IVF. You should also have an understanding of the process involved and the pros and cons of Natural IVF.

We want to empower and inform our patients. Here are answers to the most frequently asked questions about Natural IVF.

Do I have to take drugs with Natural IVF?

The term ‘Natural IVF or ‘Natural Cycle IVF’ in a literal sense implies that there are fertility drugs involved. In its purest form, the patients do not have to take any fertility stimulation drugs or drugs to prevent ovulation. But, the risk to such a physiological Natural IVF is that there is a high chance you may ovulate. In other words, the egg would be lost before the planned egg collection.

Most fertility clinics or fertility specialists will use medication to prevent ovulation. Either for a few days or a week. The medication can be an injection such as cetrotide® or pills. You will be given the trigger injection (Pregnyl®; Ovitrelle®; Gonasi®). The injection will help the egg or eggs to mature before egg retrieval.

Following egg collection, most fertility specialists will use pessaries or suppositories. These will help to maintain a good progesterone level. Progesterone is a naturally produced hormone. It makes the lining of the womb or uterus more secretory or receptive to the embryo.

Most fertility experts use the term ‘Natural IVF’ and ‘mild Stimulation IVF’ loosely. During a mild stimulation IVF, you are given fertility stimulation drugs: such as

  • Gonal F®
  • Menopur®
  • Fostimon®
  • Puregon® etc.

The dose of the stimulation drugs is less than that used in an appropriately stimulated IVF. Unlike, with natural IVF, this leads to the development of more than two follicles.

You will be taking fertility drugs or stimulation injection for approximately two weeks. Also, you will be using another injection (e.g. Cetrotide®) to prevent ovulation or loss of eggs before planned egg collection. You will be given trigger injection and progesterone supplements, for example, Utrogestan®, Cyclogest®, Lubion®, etc..

So, even with natural IVF, you will be taking some medicines which could be injections or pills. With mild stimulation IVF, you will be taking fertility drugs like stimulated IVF, for the same duration, but at fewer doses.

Are the Natural Cycle IVF success rates as good as stimulated IVF?

This is an important aspect to consider when the success rate is an important criterion.  If the patient has a  good ovarian reserve and is under 37 years, the average pregnancy rate with natural IVF is around 10-25%.

The success rate with mild stimulation may be higher than natural IVF and can go up to approximately 30%. But such patients have a success rate from stimulated IVF that ranges from 40- 70%. In short, the stimulated IVF offers a higher IVF success rate than a natural IVF or a mild stimulation IVF.

In contrast, women with a low or diminished ovarian reserve have a pregnancy rate of natural IVF or mild stimulation IVF that is comparable to that of the appropriately stimulated IVF. In such patients, the chances of a successful IVF are decreased overall whether it is a natural IVF or a stimulated IVF. In this case, a natural IVF is a good an option, especially with fewer drugs.

Am I suitable for Natural Cycle IVF?

If you have a very low ovarian reserve, which means a high Follicle stimulating hormone or FSH, very low Antimullerian Hormone or AMH and low antral follicle count or AFC, then natural cycle IVF may offer you a comparable success rate with little side effects.

On the other hand, if you have developed severe ovarian hyper stimulation syndrome during previous fertility treatments and have a regular cycle, then again natural IVF may be a better option.

For patients who have reacted or coped poorly to the fertility stimulation drugs and have a regular cycle, the natural IVF or mild IVF may be a better alternative.

But, if you have a good ovarian reserve and do not fit into any of the above descriptions, and the IVF success rate is the deciding factor, then a stimulated IVF may be better alternative. It is important that your fertility specialist considers this when discussing your treatment options.

Do I have to undergo egg collection in Natural IVF?

Yes. All patients, whether natural IVF, mild IVF or stimulated IVF have to undergo the egg collection or egg retrieval. This is usually performed under conscious sedation. Occasionally, patients, especially with a natural IVF, an egg collection with local anaesthesia can be considered. Largely, the recovery experience and duration from the egg collection would be similar whether it was natural IVF or stimulated IVF.

If unsuccessful, how long do I have to wait before starting next treatment?

This is one of the other major advantages of Natural IVF. With stimulated IVF, you will have to wait for at least two to three months before starting next treatment. With a natural IVF, you can start your next natural IVF or stimulated IVF the following month under the condition that the screening tests are satisfactory.

What are the pros and cons of natural cycle IVF or natural IVF?


The major advantage of natural IVF over stimulated IVF is that there is the use of minimal or fewer drugs. The chance of experiencing complications due to IVF treatment is lessened. Complications can be an ovarian hyper stimulation syndrome or side effects from fertility drugs.

As mentioned earlier, if the natural IVF has been unsuccessful, the next treatment can start immediately. This is especially helpful for women over 38 -40 years considering fertility treatment. But, this is just one of the factors that have to be considered.


One of the major downsides of Natural IVF is the inability to programme the treatment. This leads to a higher chance of early ovulation before the egg collection. As a result, the treatment might have to be cancelled and started again next month or later. Most fertility clinics will charge a fee for cancelled natural IVF cycle.

Secondly, you may have to attend for similar or more scans and blood tests as part of the treatment monitoring. This may lead to extra costs. Discuss the monitoring and the treatment fees with your fertility clinic or fertility specialist.