Within the field of assisted reproduction, when talking about embryo transfer, there is talk of the process of inserting the embryo or embryos generated in the laboratory into the uterus to give way to pregnancy. For this transfer to be successful, it must not be random and it is necessary that the endometrium will facilitate the implantation of the embryo.
In many cases, to prepare the endometrium, the help of drugs that mimic uterine behavior is needed. In any case, there are two types of embryo transfer: in the natural cycle and in the substituted cycle.
Embryo transfer in natural cycle
This technique takes advantage of the natural cycle of the endometrium, however, for this, women must be normally ovulatory. This means that this technique is based on the natural cycle of women with regular periods, every 21 to 35 days and lasting from 2 to 7 days.
From the 10th day of the menstrual period, a follow-up study should be done on the state of the endometrium and start monitoring ovulation. This facilitates the planning of the transfer day.
Some advantages of this method are:
- It requires less emotional weight since there is no need to prolong the hormonal medication.
- It can be carried out in patients in whom estrogen treatment is not tolerated or is contraindicated.
- It coincides with the biological cycle of women.
Embryo transfer in substituted cycle
In this technique it is necessary to use exogenous hormones that facilitate the growth of the endometrium and the implantation of the embryo. In this way, there is much more control over the period to increase the chances of a pregnancy.
This method is recommended for anovulatory patients, that is, those who do not provide any ovules during the menstrual cycle. In the same way, to patients with an irregular cycle and/or with early ovarian failure.
Some advantages of embryo transfer in substituted cycle are:
- Allows planning the transfer at the moment the patient decides
- Greater flexibility to perform ultrasound check-ups
Even so, this procedure presents some unfavorable factors such as the fact that the patient may feel more anxiety or stress from the medication; the economic budget is affected by having to get the hormones during the first months.
En Azul Fertility Experts recognize that both cycles can be performed for the transfer of a devitrified embryo, there is not much evidence that one cycle is better than the other. Each case is unique and the choice of one will depend on the patient's case.
The global trend, at present, is to perform the "freeze all" and freeze all the embryos and not transfer them fresh.
If you have more questions, you can contact us and schedule a consultation appointment. We will be happy to assist you.
