Endometrial hormone receptors and proliferation index in the periovulatory phase of stimulated embryo transfer cycles in comparison with natural cycles and relation to clinical pregnancy outcome.
OBJECTIVE
To investigate the endometrial steroid receptors and proliferation index in GnRH analogue/hMG-stimulated cycles in comparison with natural cycles and their relation to clinical pregnancy outcome.


METHODS
Prospective observational study.


METHODS
Tertiary referral center.


METHODS
Twenty-seven stimulated patients with GnRH agonist and hMG. Twenty normo-ovulatory patients were the natural cycle controls.


METHODS
Endometrial aspiration biopsies: in stimulated cycles on the day of oocyte retrieval within the ET cycle (Day OPU) (n = 20) or 2 days later (Day OPU + 2) (n = 7); in natural cycles on the natural day of ovulation (Day NO) (n = 10) or on the day of ovulation + 2 (Day NO + 2) (n = 10).


METHODS
Comparison of endometrial maturation, estrogen (ER) and P receptor (PR), and proliferation index by immunohistochemistry in natural and stimulated cycles, correlation with pregnancy outcome in stimulated cycles.


RESULTS
Stimulated cycles Day OPU showed significantly advanced endometrial maturation compared to natural cycles Day NO; stromal ER and glandular and stromal PR staining was lower in stimulated than in natural cycles, but higher on Day OPU than on Day NO + 2; proliferation index was lower in all stimulated cycles. Steroid receptors and proliferation index in stimulated cycles were unrelated to clinical pregnancy occurrence.


CONCLUSIONS
Compared to natural cycles, ovarian stimulation induced an imbalance in endometrial ER and PR and led to a profound antimitotic effect in the peri-ovulatory phase. These parameters were, however, not predictive of clinical pregnancy in cycles with ET.
Bourgain
Claire
C
Department of Pathology, European Hospital, Rome, Italy. claire.bourgain@az.vub.ac.be
Ubaldi
Filippo
F
Tavaniotou
Asimina
A
Smitz
Johan
J
Van Steirteghem
André C
AC
Devroey
Paul
P
D000328:Adult; D002455:Cell Division; D004624:Embryo Transfer; D004717:Endometrium / Q000378:metabolism*; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D010062:Ovulation Induction; D011247:Pregnancy; D011256:Pregnancy Outcome; D011446:Prospective Studies; D011987:Receptors, Steroid / Q000378:metabolism*; D020554:Sperm Injections, Intracytoplasmic
D011987:Receptors, Steroid