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Endometrial Preparation Protocol for Receivers of Oocytes

Endometrial Preparation Protocol for Receivers of Oocytes


The endometrial preparation can be carried out by previously taking contraceptives, or in a natural, spontaneous cycle.

In either case, if the patient has ovarian activity, she will need ovarian suppression treatment.

If the endometrial preparation with natural cycle has been chosen, the suppression will start on the 21st day of the previous cycle.

If contraceptives are used, ovarian suppression will begin 5 to 7 days before the end of taking the contraceptives.

Ovarian suppression guidelines:

  • Nafrelin 200 mcg. 2 intranasal applications every 12 hours, until the period. From then on, 1 intranasal application every 12 hours until the start of the Progesterone.
  • Triptorelin 0.1 mg. per day, applied subcutaneously in the abdomen, until the start of the Progesterone.
  • Triptorelin 3.75 mg., applied only once, deep intramuscular.

When menstruation presents, the recipient will begin the endometrial preparation on the first day of the cycle with one of the following guidelines:

  • Estradiol 100 mcg (Evopad 100 mcg / 24 hs®) 2 transdermal patches, changing them every 72 hs.
  • Estradiol valerate 2 mg (Progynova® 2 mg.), every 8 hours, orally.

Approximately between the 7th and 9th day from the start of the treatment, a transvaginal ultrasound should be performed to monitor the evolution of the endometrium. The measurement of the endometrium will be made at the level of the uterine fundal third. The ovaries, that should not present activity, will also be evaluated.

A suitable endometrium is considered to be one whose thickness is equal to or greater than 5 mm., besides having characteristics of trilaminar endometrium. If the measurement is lower, the possibility of increasing the estrogen dose will be assessed and the ultrasound evaluation will be repeated in approximately 4 days.

The administration of estrogens SHOULD NOT BE INTERRUPTED until the pregnancy test.

On the day of the devitrification of the oocytes, that is, the same day of the ICSI (approximately days 13th – 15th of the cycle), the recipient should start the administration of Progesterone through any of the following guidelines:

  • Micronized Progesterone 200 mg (Utrogestan® 200 mg or Progeffik® 200 mg.), every 8 hours, vaginally, starting at 4:00 p.m.
  • Progesterone (Crinone 8%) every 24 hours, vaginally, starting after 4:00 pm.
  • Progesterone (Prolutex® 25 mg.) 1 daily vial, subcutaneously (starting at 4:00 p.m.).

Once the administration of Progesterone has started it SHOULD NOT BE INTERRUPTED until the pregnancy test.

Usually, the blastocyst stage transfer occurs around the 18th – 20th day from the beginning of the endometrial preparation treatment. We tend to avoid carrying out the transfer beyond the 21st – 22nd day.

The day on which the transfer is scheduled, the recipient has to go to the clinic and the embryo transfer protocol will be followed.

If Progesterone is being administered vaginally, the recipient should administer the corresponding dose the morning of the transfer according to the usual schedule.

The patient is reminded that she MUST NOT INTERRUPT the administration of Estrogens and Progesterone until the pregnancy test.

In case of transfer at the Blastocyst stage, we will do the b-HCG 10 post transfer.

In case of positive b-HCG (> 5), we will increase the dose of the treatment:

  • Increase from 200mcg of estradiol to 300 mcg, every 72 hours.
  • Increase from 200 mg of Progesterone every 8 hours to 400 mg of Progesterone every 8 hours (2 progesterone capsules / every 8 hours).

In case of positive b-HCG with low values, it will be checked every 48 hours.

Two weeks after the first blood determination, the patient will perform the first transvaginal ultrasound control.


Download the protocol here

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