{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,3,26]],"date-time":"2026-03-26T12:37:56Z","timestamp":1774528676136,"version":"3.50.1"},"reference-count":45,"publisher":"MDPI AG","issue":"5","license":[{"start":{"date-parts":[[2023,5,17]],"date-time":"2023-05-17T00:00:00Z","timestamp":1684281600000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["JPM"],"abstract":"<jats:p>Background: Uterine blood flow determines endometrial thickness. This study examined how vaginal sildenafil citrate and estradiol valerate altered endometrial thickness, blood flow, and fertility in infertile women. Methods: This study observed 148 infertile women whose infertility was unexplained. Group 1 comprised 48 patients who received oral estradiol valerate (Cyclo-Progynova 2 mg\/12 h white tablets) from day 6 till ovulation was initiated with clomiphene citrate. A number of 50 participants in group 2 received oral sildenafil (Respatio 20 mg\/12 h film-coated tablets) for 5 days starting the day after their previous menstrual period and finishing on the day they ovulated with clomiphene citrate. Group 3 was the control group, with 50 patients receiving clomiphene citrate (Technovula 50 mg\/12 h tablets) ovulation induction from the 2nd to 7th day of cycle. All patients had transvaginal ultrasounds to determine ovulation, follicle count, and fertility. Miscarriage, ectopic pregnancy, and multiple pregnancies were monitored for three months. Results: The three groups\u2019 mean ETs differed statistically at p = 0.0004. A statistically significant difference was found between the three groups in terms of the number of follicles, with 69% of patients in group 1 having one and 31% having two or more, 76% of patients in group 2 having one and 24% having two or more, and 90% of patients in the control group having one and 10% having two or more (p = 0.038). The clinical pregnancy rates of the three groups were 58%, 46%, and 27%, respectively (p = 0.005). The distribution of all side effects was not statistically different between the three groups. Conclusion: It is possible to claim that adding oral estrogen to clomiphene citrate therapy as an adjuvant therapy can improve endometrial thickness and, as a result, increase the pregnancy rates in unexplained infertility compared to sildenafil, especially in cases where the infertility has lasted less than two years. Most people who take sildenafil end up with a mild headache.<\/jats:p>","DOI":"10.3390\/jpm13050842","type":"journal-article","created":{"date-parts":[[2023,5,17]],"date-time":"2023-05-17T02:04:05Z","timestamp":1684289045000},"page":"842","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":4,"title":["Comparative Evaluation of Sildenafil Citrate and Estrogen as an Adjuvant Therapy for Treatment of Unexplained Infertility in Women"],"prefix":"10.3390","volume":"13","author":[{"given":"Ahmed E.","family":"Altyar","sequence":"first","affiliation":[{"name":"Department of Pharmacy Practice, Faculty of Pharmacy, King Abdulaziz University, P.O. Box 80260, Jeddah 21589, Saudi Arabia"},{"name":"Pharmacy Program, Batterjee Medical College, P.O. Box 6231, Jeddah 21442, Saudi Arabia"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4916-4359","authenticated-orcid":false,"given":"Marian S.","family":"Boshra","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62511, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4434-6217","authenticated-orcid":false,"given":"Ahmed Essam","family":"Abou Warda","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, October 6 University, Giza 12585, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sherwet M.","family":"Shawkey","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Faculty of Medicine, Beni-Suef University, Beni-Suef 62511, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Sara","family":"Abdallah Mohamed Salem","sequence":"additional","affiliation":[{"name":"Department of Obstetrics and Gynecology, Faculty of Medicine, Beni-Suef University, Beni-Suef 62511, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-0781-6454","authenticated-orcid":false,"given":"Rania M.","family":"Sarhan","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, Beni-Suef University, Beni-Suef 62511, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-4067-5518","authenticated-orcid":false,"given":"Neven","family":"Sarhan","sequence":"additional","affiliation":[{"name":"Clinical Pharmacy Department, Faculty of Pharmacy, Misr International University, Cairo 11828, Egypt"}],"role":[{"role":"author","vocabulary":"crossref"}]}],"member":"1968","published-online":{"date-parts":[[2023,5,17]]},"reference":[{"key":"ref_1","unstructured":"The European IVF-Monitoring Consortium (EIM) for the European Society of Human Reproduction and Embryology (ESHRE), Wyns, C., De Geyter, C., Calhaz-Jorge, C., Kupka, M.S., Motrenko, T., Smeenk, J., Bergh, C., Tandler-Schneider, A., and Rugescu, A.A. 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