A Phase 3 interventional study of Letrozole and Clomiphene Citrate + Tamoxifen in Infertility Drugs and Infertility Involuntary, sponsored by Sana'a University. Active, not recruiting at 1 site in Yemen. Open to female participants aged 18 Years to 40 Years. Per ClinicalTrials.gov, last updated 2026-06-01.
Sponsored by Sana'a University · Phase 3, Interventional, and Treatment
Infertility is a common reproductive health problem. Ovulation induction is a key treatment for women with anovulatory infertility. Letrozole and clomiphene citrate are widely used medications for ovulation induction. Tamoxifen has also been used as an alternative or adjunct therapy.
This randomized clinical trial aims to compare the effectiveness of letrozole versus clomiphene citrate combined with tamoxifen for ovulation induction and pregnancy outcomes in infertile women. The outcomes include ovulation rate, pregnancy rate, endometrial thickness, follicular development, Miscarriage rate, and Live birth rate.
The study will be conducted at Al-Thawra Hospital in Sana'a, Yemen, under the supervision of Sana'a University.
Keywords: Infertility, Ovulation Induction, Letrozole, Clomiphene Citrate, Tamoxifen
Infertility affects a significant proportion of women worldwide and is often associated with ovulatory dysfunction. While letrozole and clomiphene citrate are standard treatments for ovulation induction, their comparative effectiveness alongside tamoxifen as adjunct therapy remains under investigation.
Infertility affects a significant proportion of women worldwide and is often associated with ovulatory dysfunction. While letrozole and clomiphene citrate are standard treatments for ovulation induction, their comparative effectiveness alongside tamoxifen as adjunct therapy remains under investigation.
This study is a randomized clinical trial enrolling women with anovulatory infertility. Participants will be assigned to receive either letrozole alone or clomiphene citrate combined with tamoxifen. Ovulation will be monitored using ultrasound and hormonal assays. Pregnancy outcomes will be recorded and analyzed to compare efficacy between the two treatment groups.
Endometrial thickness and follicular development will be evaluated throughout the treatment cycles. All participants provide informed consent before enrollment, and the study is conducted under the approval of the Sana'a University Ethics Committee at Al-Thawra Hospital, Sana'a, Yemen.
75 studies on the registry are indexed under Anovulation; 7 are open to participants now.
This study's enrollment of 240 is above the median of 80 across 52 interventional studies indexed under Anovulation.
Browse Anovulation studies →Sana'a University is the lead sponsor of 27 studies on the registry; 15 are open to participants now.
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Go through the criteria one by one — yes, no or not sure — and take the list to your doctor or the study team. Kept in this browser only.
Exclusion Criteria:
Underlined terms in the criteria open these too. Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Contraindication
A reason a treatment, test or procedure should not be given to a particular person, such as an allergy, another illness or a medicine they take.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Hypersensitivity
An allergy, or another reaction of the immune system, to a substance. “Hypersensitivity to the study drug” means a known allergic reaction to it — not every side effect a medicine can have.
Explained by clinicaltrials.gg, not part of the registry record. The study team decides who can take part.
Participants receive letrazole for ovulation induction according to the study protocol and are followed to evaluate ovulation and pregnancy outcomes.
Drug: Letrozole
Participants receive Clomiphene citrate and tamoxifen for ovulatory induction according to the study protocol and are followed to assess ovulatory and pregnancy outcomes.
Drug: Clomiphene Citrate + Tamoxifen
Letrozole was administered for ovulation induction in infertile women according to the study protocol.
Drug pages: Clomiphene · Tamoxifen
Clomiphene citrate combined with tamoxifen was administered for ovulation induction in infertile women according to the study protocol.
Ovulation rate
The primary outcome is the rate of ovulation among participants, assessed by ultrasound monitoring of follicular development and serum hormone levels.
Time frame: During three treatment cycles, from days 10 to 16 of each cycle, adjustments will be made based on individual variations in menstrual cycle length (cycle length: 21-35 days).
clinical pregnancy rate .
presence of a clinical pregnancy confirmed by transvaginal ultrasound visualization of a gestational sac with fetal heartbeat after ovulation induction treatment.
Time frame: Pregnancy was confirmed in three treatment cycles (cycle length 21-35 days) through serum beta-hCG testing two weeks post-ovulation, followed by a transvaginal ultrasound showing a gestational sac four to six weeks later.
Endometrial thickness
Measurement of Endometrial thickness in millimeters using transvaginal ultrasound on the day of ovulation trigger during ovulation induction treatment cycles.
Time frame: During each of the three treatment cycles, from cycle day 10 until the administration of the ovulation trigger, adjustments were made based on individual variations in menstrual cycle length(21-35 days).
Adverse Events/ Side effect
Incidence of adverse events (CTCAE v5.0 grades 1-3 ), including nausea, headache, hot flushes, and ovarian hyperstimulation syndrome ( OHSS), was assessed by patient questionnaire per ovulation induction cycles.
Time frame: From day 2 of the menstrual cycle (initiation of ovulation induction treatment) through up to 3 treatment cycles (cycle length: 21-35 days), until 2 weeks after the ovulation trigger.
Plan to share: No — The study involves sensitive clinical information of infertile women, and sharing these data compromises participant privacy and confidentiality.
No publications or documents are linked to this record.
This study is active, not recruiting, as verified in Mar 2026. You cannot join it, but the record below documents what was studied.
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Studies of the drugs tested here: Letrozole · Clomiphene · Tamoxifen
Sana'a University