{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,28]],"date-time":"2026-10-28T06:43:19Z","timestamp":1793169799720,"version":"4.5.0"},"reference-count":95,"publisher":"Elsevier BV","issue":"2","license":[{"start":{"date-parts":[[2020,2,1]],"date-time":"2020-02-01T00:00:00Z","timestamp":1580515200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/tdm\/userlicense\/1.0\/"},{"start":{"date-parts":[[2020,2,1]],"date-time":"2020-02-01T00:00:00Z","timestamp":1580515200000},"content-version":"tdm","delay-in-days":0,"URL":"https:\/\/www.elsevier.com\/legal\/tdmrep-license"},{"start":{"date-parts":[[2022,5,27]],"date-time":"2022-05-27T00:00:00Z","timestamp":1653609600000},"content-version":"vor","delay-in-days":846,"URL":"http:\/\/www.elsevier.com\/open-access\/userlicense\/1.0\/"}],"funder":[{"DOI":"10.13039\/100002603","name":"American Society for Reproductive Medicine","doi-asserted-by":"publisher","id":[{"id":"10.13039\/100002603","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":["clinicalkey.com","clinicalkey.com.au","clinicalkey.es","clinicalkey.fr","clinicalkey.jp","fertstert.org","elsevier.com","sciencedirect.com"],"crossmark-restriction":true},"short-container-title":["Fertility and Sterility"],"published-print":{"date-parts":[[2020,2]]},"DOI":"10.1016\/j.fertnstert.2019.10.014","type":"journal-article","created":{"date-parts":[[2020,2,24]],"date-time":"2020-02-24T18:50:01Z","timestamp":1582570201000},"page":"305-322","update-policy":"https:\/\/doi.org\/10.1016\/elsevier_cm_policy","source":"Crossref","is-referenced-by-count":177,"title":["Evidence-based treatments for couples with unexplained infertility: a guideline"],"prefix":"10.1016","volume":"113","author":[{"given":"Alan","family":"Penzias","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Kristin","family":"Bendikson","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tommaso","family":"Falcone","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Karl","family":"Hansen","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Micah","family":"Hill","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Sangita","family":"Jindal","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Jennifer","family":"Mersereau","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Catherine","family":"Racowsky","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Robert","family":"Rebar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Anne Z.","family":"Steiner","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Dale","family":"Stovall","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cigdem","family":"Tanrikut","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Suleena","family":"Kalra","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Richard","family":"Reindollar","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"William","family":"Hurd","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"78","reference":[{"key":"10.1016\/j.fertnstert.2019.10.014_bib1","doi-asserted-by":"crossref","first-page":"309","DOI":"10.1093\/humupd\/dmh029","article-title":"Overall prognosis with current treatment of infertility","volume":"10","author":"Collins","year":"2004","journal-title":"Hum Reprod Update"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib2","doi-asserted-by":"crossref","first-page":"393","DOI":"10.1016\/j.fertnstert.2017.06.005","article-title":"The International Glossary on Infertility and Fertility Care, 2017","volume":"108","author":"Zegers-Hochschild","year":"2017","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib3","doi-asserted-by":"crossref","first-page":"207","DOI":"10.1016\/S0015-0282(98)00177-0","article-title":"Efficacy of treatment for unexplained infertility","volume":"70","author":"Guzick","year":"1998","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib4","doi-asserted-by":"crossref","first-page":"1230","DOI":"10.1056\/NEJMoa1414827","article-title":"Letrozole, gonadotropin, or clomiphene for unexplained infertility","volume":"373","author":"Diamond","year":"2015","journal-title":"N Engl J Med"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib5","series-title":"2016 Assisted Reproductive Technology National Summary Report","year":"2018"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib6","doi-asserted-by":"crossref","first-page":"360","DOI":"10.1093\/humrep\/deq349","article-title":"Unexplained infertility: overall ongoing pregnancy rate and mode of conception","volume":"26","author":"Brandes","year":"2011","journal-title":"Human Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib7","doi-asserted-by":"crossref","first-page":"216","DOI":"10.1016\/S0140-6736(06)69042-9","article-title":"Intrauterine insemination with controlled ovarian hyperstimulation vs. expectant management for couples with unexplained subfertility and an intermediate prognosis: a randomised clinical trial","volume":"368","author":"Steures","year":"2006","journal-title":"Lancet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib8","doi-asserted-by":"crossref","first-page":"1575","DOI":"10.1016\/j.fertnstert.2016.02.020","article-title":"Predictors of pregnancy and live-birth in couples with unexplained infertility after ovarian stimulation-intrauterine insemination","volume":"105","author":"Hansen","year":"2016","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib9","doi-asserted-by":"crossref","first-page":"2019","DOI":"10.1093\/humrep\/deh365","article-title":"Two new prediction rules for spontaneous pregnancy leading to live birth among subfertile couples, based on the synthesis of three previous models","volume":"19","author":"Hunault","year":"2004","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib10","doi-asserted-by":"crossref","first-page":"13","DOI":"10.1016\/S0140-6736(99)04002-7","article-title":"Intrauterine insemination or in-vitro fertilisation in idiopathic subfertility and male subfertility: a randomised trial and cost-effectiveness analysis","volume":"355","author":"Goverde","year":"2000","journal-title":"Lancet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib11","doi-asserted-by":"crossref","first-page":"177","DOI":"10.1056\/NEJM199901213400302","article-title":"Efficacy of superovulation and intrauterine insemination in the treatment of infertility. National Cooperative Reproductive Medicine Network","volume":"340","author":"Guzick","year":"1999","journal-title":"NEJM"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib12","doi-asserted-by":"crossref","first-page":"258","DOI":"10.1016\/S0015-0282(16)54112-0","article-title":"Pregnancy rates after timed intercourse or intrauterine insemination after human menopausal gonadotropin stimulation of normal ovulatory cycles: a controlled study","volume":"55","author":"Martinez","year":"1991","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib13","doi-asserted-by":"crossref","first-page":"314","DOI":"10.1016\/S0015-0282(16)56524-8","article-title":"Evaluation of clomiphene citrate and human chorionic gonadotropin treatment: a\u00a0prospective, randomized, crossover study during intrauterine insemination cycles","volume":"61","author":"Arici","year":"1994","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib14","doi-asserted-by":"crossref","first-page":"a716","DOI":"10.1136\/bmj.a716","article-title":"Clomifene citrate or unstimulated intrauterine insemination compared with expectant management for unexplained infertility: pragmatic randomised controlled trial","volume":"337","author":"Bhattacharya","year":"2008","journal-title":"BMJ"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib15","doi-asserted-by":"crossref","first-page":"102","DOI":"10.1016\/S0015-0282(16)54426-4","article-title":"A prospective trial of intrauterine insemination of motile spermatozoa vs. timed intercourse","volume":"56","author":"Kirby","year":"1991","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib16","first-page":"780","article-title":"A randomized and longitudinal study of human menopausal gonadotropin with intrauterine insemination in the treatment of infertility","volume":"82","author":"Nulsen","year":"1993","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib17","doi-asserted-by":"crossref","first-page":"369","DOI":"10.1093\/humrep\/deq315","article-title":"Clomifene citrate and intrauterine insemination as first-line treatments for unexplained infertility: are they cost-effective?","volume":"26","author":"Wordsworth","year":"2011","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib18","doi-asserted-by":"crossref","first-page":"252","DOI":"10.1016\/S0015-0282(16)54111-9","article-title":"A comparative analysis of the cycle fecundity rates associated with combined human menopausal gonadotropin (hMG) and intrauterine insemination (IUI) vs. either hMG or IUI alone","volume":"55","author":"Chaffkin","year":"1991","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib19","doi-asserted-by":"crossref","first-page":"872","DOI":"10.1016\/j.fertnstert.2018.01.008","article-title":"Ovarian stimulation in infertile women treated with the use of intrauterine insemination: a cohort study from China","volume":"109","author":"Huang","year":"2018","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib20","first-page":"309","article-title":"Ovulation induction with clomiphene citrate for infertile couple","volume":"66","author":"Leanza","year":"2014","journal-title":"Minerva Ginecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib21","first-page":"303","article-title":"Unexplained infertility and ovulatory induction with menopausal gonadotropins","volume":"66","author":"Leanza","year":"2014","journal-title":"Minerva Ginecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib22","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1016\/S0015-0282(16)59052-9","article-title":"Pharmacologic induction of multiple follicular development improves the success rate of artificial insemination with husband's semen in couples with male-related or unexplained infertility","volume":"47","author":"Melis","year":"1987","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib23","doi-asserted-by":"crossref","first-page":"602","DOI":"10.1016\/S0015-0282(16)59825-2","article-title":"Unexplained infertility--the value of Pergonal superovulation combined with intrauterine insemination","volume":"49","author":"Serhal","year":"1988","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib24","doi-asserted-by":"crossref","first-page":"208","DOI":"10.1016\/S0015-0282(16)54473-2","article-title":"Transvaginal sonographic assessment of follicular and endometrial growth in spontaneous and clomiphene citrate cycles","volume":"56","author":"Randall","year":"1991","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib25","first-page":"519","article-title":"A randomised prospective trial of intrauterine insemination vs. timed intercourse in superovulated cycles with clomiphene","volume":"120","author":"Agarwal","year":"2004","journal-title":"Indian J Med Res"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib26","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1080\/00016340802638199","article-title":"Pregnancy outcome after ovulation induction with aromatase inhibitors or clomiphene citrate in unexplained infertility","volume":"88","author":"Badawy","year":"2009","journal-title":"Acta Obstet Gynecol Scand"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib27","doi-asserted-by":"crossref","first-page":"828","DOI":"10.1016\/S0015-0282(16)60674-X","article-title":"Unexplained infertility: evaluation of treatment with clomiphene citrate and human chorionic gonadotropin","volume":"51","author":"Fisch","year":"1989","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib28","doi-asserted-by":"crossref","first-page":"437","DOI":"10.1097\/AOG.0000000000003105","article-title":"Letrozole compared with clomiphene citrate for unexplained infertility: a systematic review and meta-analysis","volume":"133","author":"Eskew","year":"2019","journal-title":"Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib29","first-page":"Cd000057","article-title":"Clomiphene citrate for unexplained subfertility in women","author":"Hughes","year":"2010","journal-title":"Cochrane Database Syst Rev"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib30","doi-asserted-by":"crossref","first-page":"1205","DOI":"10.1111\/jog.12393","article-title":"Letrozole vs. clomiphene citrate for unexplained infertility: a systematic review and meta-analysis","volume":"40","author":"Liu","year":"2014","journal-title":"J Obstet Gynaecol Res"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib31","doi-asserted-by":"crossref","first-page":"1463","DOI":"10.1056\/NEJMoa1313517","article-title":"Letrozole or clomiphene for infertility in the polycystic ovary syndrome","volume":"371","author":"Legro","year":"2014","journal-title":"N Engl J Med"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib32","doi-asserted-by":"crossref","first-page":"1761","DOI":"10.1016\/j.fertnstert.2006.03.014","article-title":"Congenital malformations among 911 newborns conceived after infertility treatment with letrozole or clomiphene citrate","volume":"85","author":"Tulandi","year":"2006","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib33","doi-asserted-by":"crossref","first-page":"559","DOI":"10.1016\/S1472-6483(10)61046-2","article-title":"Randomized controlled trial of three doses of letrozole for ovulation induction in patients with unexplained infertility","volume":"14","author":"Badawy","year":"2007","journal-title":"Reprod Biomed Online"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib34","doi-asserted-by":"crossref","first-page":"1561","DOI":"10.1007\/s00404-011-1997-4","article-title":"Recombinant FSH vs. clomiphene citrate for ovarian stimulation in couples with unexplained infertility and male subfertility undergoing intrauterine insemination: a randomized trial","volume":"284","author":"Berker","year":"2011","journal-title":"Arch Gynecol Obstet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib35","doi-asserted-by":"crossref","first-page":"55","DOI":"10.1016\/0020-7292(94)02268-2","article-title":"Controlled ovarian hyperstimulation with or without intrauterine insemination for the treatment of unexplained infertility","volume":"48","author":"Gregoriou","year":"1995","journal-title":"Int J Gynaecol Obstet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib36","doi-asserted-by":"crossref","first-page":"1088","DOI":"10.1016\/S0015-0282(16)57965-5","article-title":"Ovulation induction with gonadotropins as sole treatment in infertile couples with open tubes: a randomized prospective comparison between intrauterine insemination and timed vaginal intercourse","volume":"64","author":"Melis","year":"1995","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib37","first-page":"CD003052","article-title":"Oral vs. injectable ovulation induction agents for unexplained subfertility","volume":"3","author":"Athaullah","year":"2002","journal-title":"Cochrane Database Syst Rev"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib38","doi-asserted-by":"crossref","first-page":"111","DOI":"10.1016\/0002-9378(88)90789-2","article-title":"Human menopausal gonadotropins: a justifiable therapy in ovulatory women with long-standing idiopathic infertility","volume":"158","author":"Welner","year":"1988","journal-title":"Am J Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib39","doi-asserted-by":"crossref","first-page":"1561","DOI":"10.1016\/j.fertnstert.2004.04.070","article-title":"A randomized trial of letrozole vs. clomiphene citrate in women undergoing superovulation","volume":"82","author":"Al-Fozan","year":"2004","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib40","doi-asserted-by":"crossref","first-page":"1355","DOI":"10.1016\/j.fertnstert.2008.06.013","article-title":"Clomiphene citrate or aromatase inhibitors for superovulation in women with unexplained infertility undergoing intrauterine insemination: a prospective randomized trial","volume":"92","author":"Badawy","year":"2009","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib41","doi-asserted-by":"crossref","first-page":"1863","DOI":"10.1093\/oxfordjournals.humrep.a138349","article-title":"Late low-dose pure follicle stimulating hormone for ovarian stimulation in intra-uterine insemination cycles","volume":"9","author":"Balasch","year":"1994","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib42","doi-asserted-by":"crossref","first-page":"1045","DOI":"10.1016\/j.fertnstert.2005.09.045","article-title":"Letrozole vs clomiphene citrate in patients with ovulatory infertility","volume":"85","author":"Bayar","year":"2006","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib43","doi-asserted-by":"crossref","first-page":"1866","DOI":"10.1093\/humrep\/dey268","article-title":"SUPER study group. Follicle stimulating hormone vs. clomiphene citrate in intrauterine insemination for unexplained subfertility: a randomized controlled trial","volume":"33","author":"Danhof","year":"2018","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib44","doi-asserted-by":"crossref","first-page":"792","DOI":"10.1093\/humrep\/del441","article-title":"A randomized clinical trial of clomiphene citrate vs. low dose recombinant FSH for ovarian hyperstimulation in intrauterine insemination cycles for unexplained and male subfertility","volume":"22","author":"Dankert","year":"2007","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib45","doi-asserted-by":"crossref","first-page":"1083","DOI":"10.1016\/S0015-0282(16)54009-6","article-title":"A randomized, controlled trial of clomiphene citrate and intrauterine insemination in couples with unexplained infertility or surgically corrected endometriosis","volume":"54","author":"Deaton","year":"1990","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib46","doi-asserted-by":"crossref","first-page":"90","DOI":"10.1016\/S0015-0282(99)00474-4","article-title":"A randomized prospective study comparing pregnancy rates after clomiphene citrate and human menopausal gonadotropin before intrauterine insemination","volume":"73","author":"Ecochard","year":"2000","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib47","doi-asserted-by":"crossref","first-page":"33","DOI":"10.1016\/j.ejogrb.2015.03.023","article-title":"Recombinant FSH increases live birth rates as compared to clomiphene citrate in intrauterine insemination cycles in couples with subfertility: a prospective randomized study","volume":"189","author":"Erdem","year":"2015","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib48","doi-asserted-by":"crossref","first-page":"441","DOI":"10.1016\/S0140-6736(17)32406-6","article-title":"Intrauterine insemination with ovarian stimulation vs. expectant management for unexplained infertility (TUI): a pragmatic, open-label, randomised, controlled, two-centre trial","volume":"391","author":"Farquhar","year":"2018","journal-title":"Lancet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib49","doi-asserted-by":"crossref","first-page":"84","DOI":"10.1186\/1477-7827-9-84","article-title":"Extended letrozole regimen vs. clomiphene citrate for superovulation in patients with unexplained infertility undergoing intrauterine insemination: a randomized controlled trial","volume":"9","author":"Fouda","year":"2011","journal-title":"Reprod Biol Endocrinol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib50","doi-asserted-by":"crossref","first-page":"1574","DOI":"10.1016\/j.fertnstert.2014.03.012","article-title":"A randomized clinical trial to determine optimal infertility treatment in older couples: the Forty and Over Treatment Trial (FORT-T)","volume":"101","author":"Goldman","year":"2014","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib51","doi-asserted-by":"crossref","first-page":"326","DOI":"10.1016\/j.tjog.2016.04.006","article-title":"Antagonist protocol vs. clomiphene in unexplained infertility: A randomized controlled study","volume":"55","author":"Nada","year":"2016","journal-title":"Taiwan J Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib52","doi-asserted-by":"crossref","first-page":"1079","DOI":"10.1093\/humrep\/dev062","article-title":"Low-dose human menopausal gonadotrophin vs. clomiphene citrate in subfertile couples treated with intrauterine insemination: a randomized controlled trial","volume":"30","author":"Peeraer","year":"2015","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib53","doi-asserted-by":"crossref","first-page":"888","DOI":"10.1016\/j.fertnstert.2009.04.022","article-title":"A randomized clinical trial to evaluate optimal treatment for unexplained infertility: the fast track and standard treatment (FASTT) trial","volume":"94","author":"Reindollar","year":"2010","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib54","first-page":"Cd001838","article-title":"Intra-uterine insemination for unexplained subfertility","volume":"2","author":"Veltman-Verhulst","year":"2016","journal-title":"Cochrane Database Syst Rev"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib55","doi-asserted-by":"crossref","first-page":"208","DOI":"10.1016\/S1472-6483(10)60617-7","article-title":"Letrozole vs. human menopausal gonadotrophin in women undergoing intrauterine insemination","volume":"13","author":"Baysoy","year":"2006","journal-title":"Reprod Biomed Online"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib56","doi-asserted-by":"crossref","first-page":"678","DOI":"10.1016\/j.fertnstert.2007.06.099","volume":"90","author":"Gregoriou","year":"2008","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib57","doi-asserted-by":"crossref","first-page":"243","DOI":"10.4274\/tjod.99835","article-title":"Use of clomiphene citrate alone, urinary follicle-stimulating hormone alone, or both combined sequentially in patients with unexplained subfertility undergoing intrauterine insemination: A randomized trial","volume":"15","author":"Ayaz","year":"2018","journal-title":"Turk J Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib58","doi-asserted-by":"crossref","first-page":"617","DOI":"10.3109\/01443615.2010.497873","article-title":"Clomiphene citrate or aromatase inhibitors combined with gonadotropins for superovulation in women undergoing intrauterine insemination: a prospective randomised trial","volume":"30","author":"Badawy","year":"2010","journal-title":"J Obstet Gynaecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib59","doi-asserted-by":"crossref","first-page":"1428","DOI":"10.1016\/j.fertnstert.2006.03.044","article-title":"Comparison of the efficacy of the aromatase inhibitor letrozole and clomiphene citrate as adjuvants to recombinant follicle-stimulating hormone in controlled ovarian hyperstimulation: a prospective, randomized, blinded clinical trial","volume":"86","author":"Barroso","year":"2006","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib60","doi-asserted-by":"crossref","first-page":"244","DOI":"10.1016\/j.ejogrb.2013.03.002","article-title":"Advantages of recombinant follicle-stimulating hormone over human menopausal gonadotropin for ovarian stimulation in intrauterine insemination: a randomized clinical trial in unexplained infertility","volume":"169","author":"Rashidi","year":"2013","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib61","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1007\/s10815-008-9209-2","article-title":"Comparison of the efficacy of the aromatase inhibitor letrozole and clomiphen citrate gonadotropins in controlled ovarian hyperstimulation: a prospective, simply randomized, clinical trial","volume":"25","author":"Sh Tehrani Nejad","year":"2008","journal-title":"J Assist Reprod Genet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib62","first-page":"18","article-title":"Comparison of treatment outcomes of infertile women by clomiphene citrate and letrozole with gonadotropins underwent intrauterine insemination","volume":"50","author":"Zadehmodares","year":"2012","journal-title":"Acta Med Iran"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib63","doi-asserted-by":"crossref","first-page":"88","DOI":"10.1016\/S0015-0282(00)01641-1","article-title":"Controlled ovarian hyperstimulation and intrauterine insemination for treatment of unexplained infertility should be limited to a maximum of three trials","volume":"75","author":"Aboulghar","year":"2001","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib64","doi-asserted-by":"crossref","first-page":"303","DOI":"10.1016\/S0015-0282(16)56102-0","article-title":"Ovarian superstimulation and intrauterine insemination for the treatment of unexplained infertility","volume":"60","author":"Aboulghar","year":"1993","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib65","doi-asserted-by":"crossref","first-page":"295","DOI":"10.1046\/j.1341-8076.2002.00058.x","article-title":"Minimal stimulation protocol for use with intrauterine insemination in the treatment of infertility","volume":"28","author":"Dhaliwal","year":"2002","journal-title":"J Obstet Gynaecol Res"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib66","doi-asserted-by":"crossref","first-page":"173","DOI":"10.4103\/jhrs.JHRS_120_16","article-title":"A study of controlled ovarian stimulation with clomiphene citrate or letrozole in combination with gonadotropins and IUI in unexplained infertility","volume":"10","author":"Hembram","year":"2017","journal-title":"J Hum Reprod Sci"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib67","doi-asserted-by":"crossref","first-page":"550","DOI":"10.3109\/00016349709024582","article-title":"Superovulation combined with insemination or timed intercourse in the treatment of couples with unexplained infertility and minimal endometriosis","volume":"76","author":"Isaksson","year":"1997","journal-title":"Acta Obstet Gynecol Scand"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib68","doi-asserted-by":"crossref","first-page":"349","DOI":"10.1093\/humrep\/14.2.349","article-title":"The clinical efficacy of low-dose step-up follicle stimulating hormone administration for treatment of unexplained infertility","volume":"14","author":"Sengoku","year":"1999","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib69","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1093\/humrep\/der389","article-title":"Long-term outcome in couples with unexplained subfertility and an intermediate prognosis initially randomized between expectant management and immediate treatment","volume":"27","author":"Custers","year":"2012","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib70","doi-asserted-by":"crossref","first-page":"1566","DOI":"10.1016\/j.fertnstert.2016.02.001","article-title":"Evidence-based approach to unexplained infertility: a systematic review","volume":"105","author":"Gunn","year":"2016","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib71","first-page":"Cd005354","article-title":"Recombinant vs. urinary gonadotrophin for ovarian stimulation in assisted reproductive technology cycles","author":"van Wely","year":"2011","journal-title":"Cochrane Database Syst Rev"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib72","doi-asserted-by":"crossref","first-page":"3139","DOI":"10.1093\/oxfordjournals.humrep.a135875","article-title":"Randomized comparison of ovulation induction with and without intrauterine insemination in the treatment of unexplained infertility","volume":"10","author":"Chung","year":"1995","journal-title":"Hum Reprod"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib73","doi-asserted-by":"crossref","first-page":"444","DOI":"10.1016\/j.ejogrb.2013.07.022","article-title":"A randomized study of simultaneous hCG administration with intrauterine insemination in stimulated cycles","volume":"170","author":"Aydin","year":"2013","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib74","doi-asserted-by":"crossref","first-page":"155","DOI":"10.1016\/j.ejogrb.2006.04.002","article-title":"Homologous intrauterine insemination in controlled ovarian hyperstimulation cycles: a comparison among three different regimens","volume":"129","author":"Casadei","year":"2006","journal-title":"Eur J Obstet Gynecol Reprod Biol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib75","doi-asserted-by":"crossref","first-page":"75","DOI":"10.1007\/s10815-005-9017-x","article-title":"Comparing the pregnancy rates of one vs. two intrauterine inseminations (IUIs) in male factor and idiopathic infertility","volume":"23","author":"Liu","year":"2006","journal-title":"J\u00a0Assist Reprod Genet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib76","doi-asserted-by":"crossref","first-page":"619","DOI":"10.1016\/S0015-0282(99)00326-X","article-title":"Efficacy of double intrauterine insemination in controlled ovarian hyperstimulation cycles","volume":"72","author":"Ragni","year":"1999","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib77","doi-asserted-by":"crossref","first-page":"1023","DOI":"10.1007\/s00404-011-1950-6","article-title":"Timing of intrauterine insemination: an attempt to unravel the enigma","volume":"284","author":"Rahman","year":"2011","journal-title":"Arch Gynecol Obstet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib78","doi-asserted-by":"crossref","first-page":"2913","DOI":"10.1016\/j.fertnstert.2010.06.082","article-title":"A randomized controlled trial comparing the effectiveness of single vs. double intrauterine insemination in unexplained infertility","volume":"94","author":"Rahman","year":"2010","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib79","doi-asserted-by":"crossref","first-page":"1070","DOI":"10.1016\/S0015-0282(99)00116-8","article-title":"Prospective, randomized, crossover study to evaluate the benefit of human chorionic gonadotropin-timed vs. urinary luteinizing hormone-timed intrauterine inseminations in clomiphene citrate-stimulated treatment cycles","volume":"71","author":"Zreik","year":"1999","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib80","doi-asserted-by":"crossref","first-page":"2075","DOI":"10.1016\/S0140-6736(00)05179-5","article-title":"Conventional in-vitro fertilisation vs. intracytoplasmic sperm injection for the treatment of non-male-factor infertility: a randomised controlled trial","volume":"357","author":"Bhattacharya","year":"2001","journal-title":"Lancet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib81","doi-asserted-by":"crossref","DOI":"10.1016\/j.fertnstert.2011.08.005","article-title":"Couples with unexplained subfertility and unfavorable prognosis: a randomized pilot trial comparing the effectiveness of in\u00a0vitro fertilization with elective single embryo transfer vs. intrauterine insemination with controlled ovarian stimulation","volume":"96","author":"Custers","year":"2011","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib82","doi-asserted-by":"crossref","first-page":"137","DOI":"10.1007\/s10815-005-9008-y","article-title":"A prospective randomized trial of conventional in\u00a0vitro fertilization vs. intracytoplasmic sperm injection in unexplained infertility","volume":"23","author":"Foong","year":"2006","journal-title":"J Assist Reprod Genet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib83","doi-asserted-by":"crossref","first-page":"377","DOI":"10.1023\/A:1025433128518","article-title":"Intracytoplasmic sperm injection and conventional in\u00a0vitro fertilization are complementary techniques in management of unexplained infertility","volume":"20","author":"Jaroudi","year":"2003","journal-title":"J\u00a0Assist Reprod Genet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib84","doi-asserted-by":"crossref","first-page":"1329","DOI":"10.1016\/j.fertnstert.2017.03.028","article-title":"Intrauterine insemination with gonadotropin stimulation or in\u00a0vitro fertilization for the treatment of unexplained subfertility: a randomized controlled trial","volume":"107","author":"Nandi","year":"2017","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib85","doi-asserted-by":"crossref","first-page":"171","DOI":"10.1016\/S0015-0282(97)81497-5","article-title":"The role of in\u00a0vitro fertilization and intracytoplasmic sperm injection in couples with unexplained infertility after failed intrauterine insemination","volume":"68","author":"Ruiz","year":"1997","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib86","doi-asserted-by":"crossref","first-page":"1239","DOI":"10.1016\/S0015-0282(16)55983-4","article-title":"A randomized trial of in\u00a0vitro fertilization\u00a0vs. conventional treatment for infertility","volume":"59","author":"Soliman","year":"1993","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib87","doi-asserted-by":"crossref","first-page":"336","DOI":"10.1016\/j.rbmo.2013.10.021","article-title":"IVF with planned single-embryo transfer vs. IUI with ovarian stimulation in couples with unexplained subfertility: an economic analysis","volume":"28","author":"van Rumste","year":"2014","journal-title":"Reprod Biomed Online"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib88","doi-asserted-by":"crossref","first-page":"38","DOI":"10.1007\/BF02068867","article-title":"Intracytoplasmic sperm injection and conventional in\u00a0vitro fertilization for sibling oocytes in cases of unexplained infertility and borderline semen","volume":"13","author":"Aboulghar","year":"1996","journal-title":"J Assist Reprod Genet"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib89","doi-asserted-by":"crossref","first-page":"584","DOI":"10.1016\/S1472-6483(10)61107-8","article-title":"A strategy for treatment of couples with unexplained infertility who failed to conceive after intrauterine insemination","volume":"8","author":"Bungum","year":"2004","journal-title":"Reprod Biomed Online"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib90","first-page":"150","article-title":"Conventional oocyte insemination may result in a better pregnancy outcome than intracytoplasmic sperm injection (ICSI) for unexplained infertility","volume":"36","author":"Check","year":"2009","journal-title":"Clin Exp Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib91","first-page":"203","article-title":"Effect of method of oocyte fertilization on fertilization, pregnancy and implantation rates in women with unexplained infertility","volume":"38","author":"Check","year":"2011","journal-title":"Clin Exp Obstet Gynecol"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib92","first-page":"1155","article-title":"Comparative study of intracytoplasmic sperm injection and in\u00a0vitro fertilization with high insemination concentration in sibling oocytes in the treatment of unexplained infertility","volume":"91","author":"Chiamchanya","year":"2008","journal-title":"J Med Assoc Thai"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib93","doi-asserted-by":"crossref","first-page":"334","DOI":"10.1016\/S0015-0282(99)00518-X","article-title":"Treatment of patients with long-standing unexplained subfertility with in\u00a0vitro fertilization","volume":"73","author":"Donderwinkel","year":"2000","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib94","doi-asserted-by":"crossref","first-page":"229","DOI":"10.1016\/S0015-0282(01)02978-8","article-title":"In\u00a0vitro fertilization-intracytoplasmic sperm injection split: an insemination method to prevent fertilization failure","volume":"77","author":"Hershlag","year":"2002","journal-title":"Fertil Steril"},{"key":"10.1016\/j.fertnstert.2019.10.014_bib95","doi-asserted-by":"crossref","first-page":"704","DOI":"10.1016\/j.fertnstert.2013.04.038","article-title":"Does intracytoplasmic sperm injection improve the fertilization rate and decrease the total fertilization failure rate in couples with well-defined unexplained infertility? A systematic review and meta-analysis","volume":"100","author":"Johnson","year":"2013","journal-title":"Fertil Steril"}],"container-title":["Fertility and Sterility"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0015028219324847?httpAccept=text\/xml","content-type":"text\/xml","content-version":"vor","intended-application":"text-mining"},{"URL":"https:\/\/api.elsevier.com\/content\/article\/PII:S0015028219324847?httpAccept=text\/plain","content-type":"text\/plain","content-version":"vor","intended-application":"text-mining"}],"deposited":{"date-parts":[[2025,9,16]],"date-time":"2025-09-16T08:25:25Z","timestamp":1758011125000},"score":1,"resource":{"primary":{"URL":"https:\/\/linkinghub.elsevier.com\/retrieve\/pii\/S0015028219324847"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2020,2]]},"references-count":95,"journal-issue":{"issue":"2","published-print":{"date-parts":[[2020,2]]}},"alternative-id":["S0015028219324847"],"URL":"https:\/\/doi.org\/10.1016\/j.fertnstert.2019.10.014","relation":{},"ISSN":["0015-0282"],"issn-type":[{"value":"0015-0282","type":"print"}],"subject":[],"published":{"date-parts":[[2020,2]]},"assertion":[{"value":"Elsevier","name":"publisher","label":"This article is maintained by"},{"value":"Evidence-based treatments for couples with unexplained infertility: a guideline","name":"articletitle","label":"Article Title"},{"value":"Fertility and Sterility","name":"journaltitle","label":"Journal Title"},{"value":"https:\/\/doi.org\/10.1016\/j.fertnstert.2019.10.014","name":"articlelink","label":"CrossRef DOI link to publisher maintained version"},{"value":"article","name":"content_type","label":"Content Type"},{"value":"\u00a92019 American Society for Reproductive Medicine, Published by Elsevier Inc.","name":"copyright","label":"Copyright"}]}}