**4.4. Oral micronized progesterone vs. I.M progesterone**

Oral micronized progesterone for luteal phase support in ART not only results in significantly lower rates of pregnancy and implantation compared with those for I.M. , hCG or progesterone, but also causes more side effects [36] .In a prospective randomized study, the implantation rate was significantly lower in the oral micronized progesterone arm compared with I.M. progesterone. There was no significant difference in pregnancy rate between both groups [37] As mentioned above parenteral administration of progesterone, vaginally or I.M, does not subject the compound to the significant metabolic consequences of oral administration. Progesterone administered orally is subjected to first-pass prehepatic and hepatic metabolism [23].

Luteal Phase Support in ART: An Update 161

progesterone permeates through the mucosal tissue. The depletion of dissolved progesterone in the formulation is replenished by the dissolution of suspended

A prospective randomized study [45] compared the luteal serum hormone level, effectiveness and tolerability of two different vaginal formulations of micronized progesterone, vaginal pessaries (Ellios) and capsules (Uterogestan) , used for luteal phase support after an in vitro fertilization (IVF). Patients received Ellios pessaries (2 times 200-mg pessary/day) or Utrogestan capsules (2 100-mg capsules, two times a day). Progesterone was administered from the day of oocyte pickup (day 0) until menses or up to 10 weeks in pregnant patients. The outcome measures showed that progesterone levels on days 0, 9, 16 were not statistically different between the two formulations. The pregnancy rate were similar in the two groups (25.5% vs. 18.6%), whereas tolerance was signicantly better in

Another randomized trial [46] compared side effects and patient convenience of vaginal progesterone suppositories (Cyclogest) and vaginal progesterone tablets (Endometrin) used for luteal phase support in in vitro fertilization/embryo transfer cycles using pituitary. downregulation. One hundred and thirty-two infertile patients were randomized on the day of embryo transfer by a computer-generated randomization list in sealed envelopes to receive either Cyclogest 400 mg or Endometrin 100 mg twice daily for 14 days. On days 6 and 16 after ET, they rated side effects and patient convenience into four grades: none, mild, moderate and severe by completing a questionnaire.The results showed no signicant differences in perineal irritation on days 6 and 16 after embryo transfer between the two groups, although there was a trend of fewer patients with perineal irritation in the Endometrin group. Signicantly more patients in the Endometrin group had difculty of administration on day 6 after embryo transfer. There were no differences in the hormonal prole on day 6 after embryo transfer and IVF outcomes between the two groups. The study concluded that there was no difference in perineal irritation after the use of Cyclogest suppositories or Endometrin tablets for luteal phase support although more patients found

The first prospective randomized trial comparing vaginal cream Crinone 8% [47] investigated 126 patients undergoing cycles of IVF / ICSI. Patients received either Crinone 8% (n = 73) vaginally once daily or two Utrogest capsules (n=53) vaginally three times daily (600 mg). Clinical pregnancy rates were comparable (28.8 versus 18.9%), as were clinical abortion rates until 12 weeks of gestation (14.3 versus 10.0%) and clinical ongoing pregnancy rates (24.7 versus 17.0%) in the Crinone 8% and Utrogest groups, respectively.

pessaries` group versus capsules` group (vaginal discharge: 43% vs. 82%).

progesterone particles

**5.1. Pessaries vs. capsules** 

**5.2. Suppositories vs. tablets** 

administration of Endometrin tablets difficult.

**5.3. Gel vs. capsule** 
