The effect of ethinyl estradiol on endometrial thickness and uterine volume during ovulation induction by clomiphene citrate.
OBJECTIVE
To assess the deleterious effect of clomiphene citrate (CC) on the development of the endometrium and its improvement by the addition of ethinyl estradiol (E2). PARTICIPATING PATIENTS: Infertility-treated patients, monitored for induction of ovulation or timing of insemination (control group).


METHODS
We studied four groups of women during an ovulatory cycle with various treatment schedules. Group 1: untreated patients; group 2: patients treated by CC; group 3: patients treated by CC + ethinyl E2; group 4: patients treated by human menopausal gonadotropin. Follow-up of the patients was done by vaginal ultrasonography and measurements of blood E2.


RESULTS
In the group treated by CC, both endometrial thickness and uterine volume growth during the follicular phase were lower as compared with untreated controls and menotropin-treated patients. The addition of ethinyl E2 to these patients reversed this deleterious effect of CC without interfering with ovulation.


CONCLUSIONS
Ethinyl E2 may reverse the deleterious effect of CC on endometrial development during the follicular phase.
Yagel
S
S
Department of Obstetrics/Gynecology, Hadassah University Hospital, Mt. Scopus, Jerusalem, Israel.
Ben-Chetrit
A
A
Anteby
E
E
Zacut
D
D
Hochner-Celnikier
D
D
Ron
M
M
D000328:Adult; D002996:Clomiphene / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D004717:Endometrium / Q000187:drug effects / Q000473:pathology*; D004958:Estradiol / Q000097:blood; D004997:Ethinyl Estradiol / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy* / Q000473:pathology; D008596:Menotropins / Q000627:therapeutic use; D010060:Ovulation; D010062:Ovulation Induction; D014599:Uterus / Q000187:drug effects / Q000473:pathology* / Q000503:physiopathology
D002996:Clomiphene; D004997:Ethinyl Estradiol; D004958:Estradiol; D008596:Menotropins