ABSTRACT
To achieve optimal endometrial growth, exogenous 17b-estradiol (micronized) is administered, starting on the day of oocyte retrieval. The dosage used depends on the endometrial thickness on the day of oocyte retrieval. When endometrial thickness is less than 6 mm, 12 mg a day is started; if the thickness is between 6 and 8 mm, then 10 mg a day is started; and if the thickness is more than 8 mm, then 6 mg is used – all in three divided doses. When an extremely thin endometrium (i.e. <4 mm) is recorded on ultrasound scan prior to collection, we have recently begun to administer estradiol treatment before oocyte collection. We are currently investigating an alternative approach whereby in-vitro matured oocytes are vitrified when the endometrial lining is very thin53. The endometrium is then prepared in an artificial cycle and, once it reaches a thickness of 8 mm, the oocytes are thawed, fertilized, and transferred. In an IVM treatment cycle, luteal support with daily intramuscular injections of progesterone in oil or Prometrium 200 mg (Schering Canada) three times per day, is started on the day that oocyte maturation is achieved and ICSI is performed. Estradiol and progesterone supplementation is continued until the twelfth week of pregnancy.
