The use of drugs has dramatically changed the way IVF is achieved. However, pregnancy can also be achieved without their use, a method that has its own advantages and disadvantages.

The first cycles of in vitro fertilization since 1978 were done without stimulation of the ovaries with drugs and were intended to find and fertilize the one and only egg that the woman produces in each of her natural cycles. In the next 30 years to the present day, infertility treatments have been largely replaced by IVF using drugs.

In vitro fertilization without drugs (in a natural cycle).

In vitro fertilization in a natural cycle has several advantages. It is associated with an almost zero rate of multiple pregnancy and zero risk of ovarian hyperstimulation syndrome. Per natural cycle, IVF is a cheaper and less time-consuming treatment, less physically and emotionally demanding for patients. But it is also less effective.

The effectiveness of IVF in a natural cycle is hindered by the high rates of cancellation due to premature maturation of the eggs, but also the possibility that the follicles will not contain an egg.

For which women is this treatment indicated?

Women with low ovarian sufficiency who do not produce eggs with the use of medication. These women have low levels in a blood test – AMH (anti-mullerian hormone).

Women who are not allowed to take gonadotropins – e.g. with a history of hormone-dependent cancer.

Women who choose for personal reasons – e.g. religious not to take drugs and not to produce many eggs.

What is the process?

In a natural cycle, only one follicle with one egg inside usually develops. The technique of in vitro fertilization in a natural cycle is the fertilization of this egg without the use of drugs to stimulate the ovary. Patients are monitored with ultrasound and an oocyte collection is performed. If the egg retrieval is successful, the egg is fertilized, the embryo is created and transferred to the uterus or cryopreserved. The same technical procedures are used for egg retrieval, fertilization and embryo transfer, but only for one egg.

The disadvantage of the method is that in about 20% of cases no egg is retrieved. An additional 20% of cycles do not produce any embryos and do not result in embryo transfer.

Collect & Freeze method

A variant of using the natural cycle is the sequential collection of eggs and cryopreservation (Collect & freeze), i.e. that of repeated attempts, in which the eggs found each month are fertilized and the embryos are frozen. When 2-4 embryos are collected, an embryo transfer is performed with all the thawed embryos.

The success rates of this method rival those of drug-assisted IVF cycles, especially for women with minimal egg production.

However, we must emphasize that it usually takes several cycles to finally collect 3 embryos of good quality. This is quite mentally demanding for some women, but it is usually the only option they have before resorting to egg donation.

In vitro fertilization with minimal drugs (mini IVF)

This method uses lower doses of drugs to mature 2-4 eggs, followed by egg retrieval, fertilization and embryo transfer. This effort is more successful than the natural cycle and has many benefits.

The opposite of minimal stimulation is not maximal stimulation, but achieving optimal stimulation, a goal toward which we all strive, and the intent of medicine is always to achieve the best results.

IVF with little or no medication is a low-risk and woman-friendly procedure with good results and success rates, but it should be done in selected cases.