Anencephaly Diagnosed at Routine Obstetric Ultrasound Scan

Anencephaly Diagnosed at Routine Obstetric Ultrasound Scan | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Case Report Anencephaly Diagnosed at Routine Obstetric Ultrasound Scan Osato Asemota-Igbinovia, Tobechukwu Marchie, Kenneth Eze, Sulaimon Araromi, and 1 more This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9157131/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract Anencephaly is a lethal neural tube defect characterized by the absence of cerebral hemispheres and the cranial vault. We report a case of anencephaly diagnosed during routine antenatal ultrasonography in the third trimester of a 39-year-old multiparous woman presenting with reduced fetal movements. Imaging findings included the absence of the cranial vault and gross polyhydramnios. This case highlights the sonographic features, clinical implications, and importance of prenatal screening in the diagnosis and management of anencephaly. Anencephaly Neural Tube Defect Obstetric Ultrasound Polyhydramnios Prenatal Diagnosis Folic Acid Supplementation Figures Figure 1 Figure 2 Introduction Anencephaly is a severe and universally fatal neural tube defect (NTD) [ 3 ], and while its pathogenesis and clinical features are well-documented [ 6 ], this case underscores the crucial role of routine prenatal ultrasonography in detecting such anomalies [ 5 ], even in patients with minimal or no antenatal care. The significance of this case lies in several key areas. First, it illustrates the diagnostic timing and methodology, showing how anencephaly can be accurately diagnosed via sonography during the third trimester, based on hallmark features like absence of the cranial vault and polyhydramnios [ 5 ] [ 7 ]. It highlights the diagnostic value of late-pregnancy imaging in underserved or low-resource settings where early screening may not occur. Second, the clinical implications in real-world settings are presented, as the case reflects the real-world challenges of antenatal care access in certain populations, particularly in developing regions. It presents the sonographic findings and clinical management of an anencephalic fetus in a multiparous woman who had not engaged in prenatal screening. Third, the case provides educational and preventive value, emphasizing the importance of folic acid supplementation and early antenatal visits, serving as a teaching point for clinicians and public health professionals. It also contributes to global efforts to raise awareness of preventable NTDs and the recurrence risk reduction achievable with folate [ 4 ]. Finally, though anencephaly is not rare [ 1 ], individual case reports remain valuable in radiological literature for reinforcing recognition of typical imaging features, such as the "Mickey Mouse" sign [ 5 ], and for expanding the geographical and clinical context of documented cases. The report supplements existing literature with data from Nigeria, where epidemiologic documentation is less robust compared to Western countries [ 8 ]. Case Presentation A 39-year-old multiparous petty trader, presented at the obstetric emergency room due to reduced fetal movements. She had not attended antenatal care during the pregnancy but reported hospital-supervised deliveries for her previous pregnancies, all of which resulted in healthy infants. She denied a history of hypertension, diabetes, smoking, or alcohol consumption. On examination, the patient was well-nourished and appeared healthy. Her weight was 70 kg, height 1.72 m, and blood pressure 110/80 mmHg. Symphysio-fundal height measured 36 cm, but the fetal skull was difficult to palpate. The fetal heart rate was 138 beats per minute. Laboratory results were unremarkable. Obstetric ultrasonography revealed a viable singleton intrauterine fetus in vertex presentation and longitudinal lie, with gestational age estimated at 35 weeks based on femoral length. The skull vault was absent, and prominent eyeballs were noted. Associated polyhydramnios was evident, with a single amniotic fluid pocket measuring 10 mm (Figs. 1 and 2 ). No additional fetal anomalies were detected. FINDINGS: Obstetric ultrasound demonstrates the absence of the cranial vault above a prominent orbit. TECHNIQUE: Transabdominal ultrasound using a 3.5 MHz probe, single longitudinal plane. FINDINGS: Obstetric ultrasound reveals deep amniotic fluid pockets consistent with polyhydramnios. TECHNIQUE: Transabdominal ultrasound using a 3.5 MHz probe, single transverse plane. A diagnosis of anencephaly was established based on the ultrasonographic findings. The patient was counselled about the diagnosis, prognosis, and management options. She consented to an induction of labour, which resulted in the delivery of a live female anencephalic fetus weighing 2.25 kg. The infant died shortly after birth. Discussion Anencephaly is the most common open neural tube defect, with an average worldwide incidence of 1.4-2 per 1000 live births [ 1 ]. It results from the failure of neural tube closure at the cephalic end during the second to third week of embryonic development, leading to the absence of the forebrain, meninges, calvarium, and scalp [ 2 ]. The condition is invariably fatal, resulting in stillbirth or early neonatal death [ 3 ]. Geographically, the incidence of anencephaly varies, with an overall incidence of approximately 1 in 1000 births in Africa, lower rates among African blacks, and higher rates among Caucasians in regions such as Ireland and Wales [ 3 ]. Risk factors include genetic predisposition, environmental exposures, dietary deficiencies (notably folate), and teratogenic agents [ 4 ]. Anencephaly can occur as an isolated defect, as observed in this case, or as part of a syndrome [ 1 ]. Polyhydramnios, present in up to 85% of cases after 25 weeks gestation, was evident in this patient [ 5 ]. Ultrasonographic findings included the absence of the cranial vault, prominent eyeballs, and polyhydramnios. These hallmark features are diagnostic of anencephaly, which can be identified as early as 11 weeks gestation using ultrasonography. The "Mickey Mouse" sign—protruding cerebral tissue in the absence of a surrounding calvarium—is a key marker for early detection [ 6 ]. Anencephaly is uniformly fatal, with no viable treatment options. Prenatal diagnosis allows for early counseling and planning. This patient was counseled about the prognosis and consented to induction of labor, resulting in the delivery of a live but nonviable anencephalic fetus. The recurrence risk of neural tube defects in subsequent pregnancies is 3–4% without folic acid supplementation and decreases to less than 1% with adequate supplementation. The differential diagnoses for anencephaly include other neural tube defects such as spina bifida and encephalocele, as well as cranial pathologies like severe microcephaly and amniotic band syndrome. Distinguishing features on imaging, such as the absence of the calvarium and the characteristic protrusion of facial structures, aid in differentiating anencephaly from these conditions [ 7 ]. Associated findings, such as polyhydramnios and the "Mickey Mouse" sign, further confirm the diagnosis [ 8 ]. Conclusions Anencephaly is a severe and universally fatal neural tube defect. Routine prenatal ultrasonography is critical for diagnosing congenital anomalies like anencephaly, enabling timely counselling and appropriate management to optimise maternal and neonatal outcomes. This case report reinforces the importance of early diagnosis and highlights the sonographic features and clinical implications of anencephaly in a patient with limited antenatal care. The recurrence risk of neural tube defects in subsequent pregnancies is significantly reduced with adequate folic acid supplementation. Declarations Consent to Participate and Publish: "Informed consent was obtained from the patient for the participation in this clinical case study and for the publication of the associated clinical details and images. All identifying information has been removed to ensure patient anonymity. References Salari N, Larijani B, Abdolmaleki S et al (2022) Global prevalence of congenital anencephaly: a comprehensive systematic review and meta-analysis. Reprod Health 19(1):201. 10.1186/s12978-022-01509-4 Jiang Z, Wang J, Yu X, Li C, Shao Y, Wang Z (2020) Comparative efficacy and safety of traditional Chinese patent medicine for anxiety disorders in children or adolescence. Med (Baltim) 99(39):e22274. 10.1097/MD.0000000000022274 Nunes NA, Tekulwar NW, Prasad R (2024) A Devastating Diagnosis: Anencephaly With Unexpected Fetal Heartbeat. Cureus 16(8):e67321. 10.7759/cureus.67321 Abebe M, Afework M, Emamu B, Teshome D (2021) Risk Factors of Anencephaly: A Case–Control Study in Dessie Town, North East Ethiopia. Pediatr Heal Med Ther 12:499–506. 10.2147/PHMT.S332561 Szkodziak P, Węgrzyn P, Wójcik-Gryciuk A et al (2020) The role of the 'beret' sign and other markers in ultrasound diagnostic of the acrania–exencephaly–anencephaly sequence stages. Arch Gynecol Obstet 302(3):619–628. 10.1007/s00404-020-05650-y Wiltgen A (2020) Anencephaly. In: Radiopaedia.org. Radiopaedia.org; 10.53347/rID-84126 Bartoš V, Káčeríková O (2023) Fetal acrania: A case report. Acta Facicae Naissensis 40(1):116–122. 10.5937/afmnai40-36356 Oblitey JN, Antwi WK, Botwe BO, Oblitey MK (2021) Ultrasound diagnosis of acrania with major low–lying placenta and polyhydramnios; case report. Ghana Med J 55(2):165–168. 10.4314/gmj.v55i2.12 Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-9157131","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Case Report","associatedPublications":[],"authors":[{"id":608132248,"identity":"b78cae93-f7ea-4725-8997-aed09b97a383","order_by":0,"name":"Osato 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citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], even in patients with minimal or no antenatal care. The significance of this case lies in several key areas. First, it illustrates the diagnostic timing and methodology, showing how anencephaly can be accurately diagnosed via sonography during the third trimester, based on hallmark features like absence of the cranial vault and polyhydramnios [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e] [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. It highlights the diagnostic value of late-pregnancy imaging in underserved or low-resource settings where early screening may not occur. Second, the clinical implications in real-world settings are presented, as the case reflects the real-world challenges of antenatal care access in certain populations, particularly in developing regions. It presents the sonographic findings and clinical management of an anencephalic fetus in a multiparous woman who had not engaged in prenatal screening. Third, the case provides educational and preventive value, emphasizing the importance of folic acid supplementation and early antenatal visits, serving as a teaching point for clinicians and public health professionals. It also contributes to global efforts to raise awareness of preventable NTDs and the recurrence risk reduction achievable with folate [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e]. Finally, though anencephaly is not rare [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e], individual case reports remain valuable in radiological literature for reinforcing recognition of typical imaging features, such as the \"Mickey Mouse\" sign [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e], and for expanding the geographical and clinical context of documented cases. The report supplements existing literature with data from Nigeria, where epidemiologic documentation is less robust compared to Western countries [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e"},{"header":"Case Presentation","content":"\u003cp\u003eA 39-year-old multiparous petty trader, presented at the obstetric emergency room due to reduced fetal movements. She had not attended antenatal care during the pregnancy but reported hospital-supervised deliveries for her previous pregnancies, all of which resulted in healthy infants. She denied a history of hypertension, diabetes, smoking, or alcohol consumption.\u003c/p\u003e \u003cp\u003eOn examination, the patient was well-nourished and appeared healthy. Her weight was 70 kg, height 1.72 m, and blood pressure 110/80 mmHg. Symphysio-fundal height measured 36 cm, but the fetal skull was difficult to palpate. The fetal heart rate was 138 beats per minute. Laboratory results were unremarkable.\u003c/p\u003e \u003cp\u003eObstetric ultrasonography revealed a viable singleton intrauterine fetus in vertex presentation and longitudinal lie, with gestational age estimated at 35 weeks based on femoral length. The skull vault was absent, and prominent eyeballs were noted. Associated polyhydramnios was evident, with a single amniotic fluid pocket measuring 10 mm (Figs.\u0026nbsp;\u003cspan refid=\"Fig1\" class=\"InternalRef\"\u003e1\u003c/span\u003e and \u003cspan refid=\"Fig2\" class=\"InternalRef\"\u003e2\u003c/span\u003e). No additional fetal anomalies were detected.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFINDINGS: Obstetric ultrasound demonstrates the absence of the cranial vault above a prominent orbit. TECHNIQUE: Transabdominal ultrasound using a 3.5 MHz probe, single longitudinal plane.\u003c/p\u003e \u003cp\u003e \u003c/p\u003e \u003cp\u003eFINDINGS: Obstetric ultrasound reveals deep amniotic fluid pockets consistent with polyhydramnios. TECHNIQUE: Transabdominal ultrasound using a 3.5 MHz probe, single transverse plane.\u003c/p\u003e \u003cp\u003eA diagnosis of anencephaly was established based on the ultrasonographic findings.\u003c/p\u003e \u003cp\u003eThe patient was counselled about the diagnosis, prognosis, and management options. She consented to an induction of labour, which resulted in the delivery of a live female anencephalic fetus weighing 2.25 kg. The infant died shortly after birth.\u003c/p\u003e"},{"header":"Discussion","content":"\u003cp\u003eAnencephaly is the most common open neural tube defect, with an average worldwide incidence of 1.4-2 per 1000 live births [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. It results from the failure of neural tube closure at the cephalic end during the second to third week of embryonic development, leading to the absence of the forebrain, meninges, calvarium, and scalp [\u003cspan citationid=\"CR2\" class=\"CitationRef\"\u003e2\u003c/span\u003e]. The condition is invariably fatal, resulting in stillbirth or early neonatal death [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Geographically, the incidence of anencephaly varies, with an overall incidence of approximately 1 in 1000 births in Africa, lower rates among African blacks, and higher rates among Caucasians in regions such as Ireland and Wales [\u003cspan citationid=\"CR3\" class=\"CitationRef\"\u003e3\u003c/span\u003e]. Risk factors include genetic predisposition, environmental exposures, dietary deficiencies (notably folate), and teratogenic agents [\u003cspan citationid=\"CR4\" class=\"CitationRef\"\u003e4\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAnencephaly can occur as an isolated defect, as observed in this case, or as part of a syndrome [\u003cspan citationid=\"CR1\" class=\"CitationRef\"\u003e1\u003c/span\u003e]. Polyhydramnios, present in up to 85% of cases after 25 weeks gestation, was evident in this patient [\u003cspan citationid=\"CR5\" class=\"CitationRef\"\u003e5\u003c/span\u003e]. Ultrasonographic findings included the absence of the cranial vault, prominent eyeballs, and polyhydramnios. These hallmark features are diagnostic of anencephaly, which can be identified as early as 11 weeks gestation using ultrasonography. The \"Mickey Mouse\" sign\u0026mdash;protruding cerebral tissue in the absence of a surrounding calvarium\u0026mdash;is a key marker for early detection [\u003cspan citationid=\"CR6\" class=\"CitationRef\"\u003e6\u003c/span\u003e].\u003c/p\u003e \u003cp\u003eAnencephaly is uniformly fatal, with no viable treatment options. Prenatal diagnosis allows for early counseling and planning. This patient was counseled about the prognosis and consented to induction of labor, resulting in the delivery of a live but nonviable anencephalic fetus. The recurrence risk of neural tube defects in subsequent pregnancies is 3\u0026ndash;4% without folic acid supplementation and decreases to less than 1% with adequate supplementation.\u003c/p\u003e \u003cp\u003eThe differential diagnoses for anencephaly include other neural tube defects such as spina bifida and encephalocele, as well as cranial pathologies like severe microcephaly and amniotic band syndrome. Distinguishing features on imaging, such as the absence of the calvarium and the characteristic protrusion of facial structures, aid in differentiating anencephaly from these conditions [\u003cspan citationid=\"CR7\" class=\"CitationRef\"\u003e7\u003c/span\u003e]. Associated findings, such as polyhydramnios and the \"Mickey Mouse\" sign, further confirm the diagnosis [\u003cspan citationid=\"CR8\" class=\"CitationRef\"\u003e8\u003c/span\u003e].\u003c/p\u003e"},{"header":"Conclusions","content":"\u003cp\u003eAnencephaly is a severe and universally fatal neural tube defect. Routine prenatal ultrasonography is critical for diagnosing congenital anomalies like anencephaly, enabling timely counselling and appropriate management to optimise maternal and neonatal outcomes. This case report reinforces the importance of early diagnosis and highlights the sonographic features and clinical implications of anencephaly in a patient with limited antenatal care. The recurrence risk of neural tube defects in subsequent pregnancies is significantly reduced with adequate folic acid supplementation.\u003c/p\u003e"},{"header":"Declarations","content":"\u003cp\u003eConsent to Participate and Publish: \"Informed consent was obtained from the patient for the participation in this clinical case study and for the publication of the associated clinical details and images. All identifying information has been removed to ensure patient anonymity.\u003c/p\u003e"},{"header":"References","content":"\u003col\u003e\u003cli\u003e\u003cspan\u003eSalari N, Larijani B, Abdolmaleki S et al (2022) Global prevalence of congenital anencephaly: a comprehensive systematic review and meta-analysis. Reprod Health 19(1):201. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1186/s12978-022-01509-4\u003c/span\u003e\u003cspan address=\"10.1186/s12978-022-01509-4\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eJiang Z, Wang J, Yu X, Li C, Shao Y, Wang Z (2020) Comparative efficacy and safety of traditional Chinese patent medicine for anxiety disorders in children or adolescence. Med (Baltim) 99(39):e22274. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1097/MD.0000000000022274\u003c/span\u003e\u003cspan address=\"10.1097/MD.0000000000022274\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eNunes NA, Tekulwar NW, Prasad R (2024) A Devastating Diagnosis: Anencephaly With Unexpected Fetal Heartbeat. Cureus 16(8):e67321. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.7759/cureus.67321\u003c/span\u003e\u003cspan address=\"10.7759/cureus.67321\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eAbebe M, Afework M, Emamu B, Teshome D (2021) Risk Factors of Anencephaly: A Case\u0026ndash;Control Study in Dessie Town, North East Ethiopia. Pediatr Heal Med Ther 12:499\u0026ndash;506. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.2147/PHMT.S332561\u003c/span\u003e\u003cspan address=\"10.2147/PHMT.S332561\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eSzkodziak P, Węgrzyn P, W\u0026oacute;jcik-Gryciuk A et al (2020) The role of the 'beret' sign and other markers in ultrasound diagnostic of the acrania\u0026ndash;exencephaly\u0026ndash;anencephaly sequence stages. Arch Gynecol Obstet 302(3):619\u0026ndash;628. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.1007/s00404-020-05650-y\u003c/span\u003e\u003cspan address=\"10.1007/s00404-020-05650-y\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e \u003cli\u003e\u003cspan\u003eWiltgen A (2020) Anencephaly. In: Radiopaedia.org. 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Ghana Med J 55(2):165\u0026ndash;168. \u003cspan class=\"ExternalRef\"\u003e\u003cspan class=\"RefSource\"\u003e10.4314/gmj.v55i2.12\u003c/span\u003e\u003cspan address=\"10.4314/gmj.v55i2.12\" targettype=\"DOI\" class=\"RefTarget\"\u003e\u003c/span\u003e\u003c/span\u003e\u003c/span\u003e\u003c/li\u003e\u003c/ol\u003e"}],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":true,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"University of Hull","isAcceptedByJournal":false,"isAuthorSuppliedPdf":false,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":false,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":"Anencephaly, Neural Tube Defect, Obstetric Ultrasound, Polyhydramnios, Prenatal Diagnosis, Folic Acid Supplementation","lastPublishedDoi":"10.21203/rs.3.rs-9157131/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9157131/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eAnencephaly is a lethal neural tube defect characterized by the absence of cerebral hemispheres and the cranial vault. We report a case of anencephaly diagnosed during routine antenatal ultrasonography in the third trimester of a 39-year-old multiparous woman presenting with reduced fetal movements. Imaging findings included the absence of the cranial vault and gross polyhydramnios. This case highlights the sonographic features, clinical implications, and importance of prenatal screening in the diagnosis and management of anencephaly.\u003c/p\u003e","manuscriptTitle":"Anencephaly Diagnosed at Routine Obstetric Ultrasound Scan","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-03-23 08:31:00","doi":"10.21203/rs.3.rs-9157131/v1","editorialEvents":[{"type":"communityComments","content":0}],"status":"published","journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true}}],"origin":"","ownerIdentity":"bdd4bf6d-468a-4559-8a3f-de99daf89e56","owner":[],"postedDate":"March 23rd, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"posted","subjectAreas":[],"tags":[],"updatedAt":"2026-03-23T08:31:00+00:00","versionOfRecord":[],"versionCreatedAt":"2026-03-23 08:31:00","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9157131","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9157131","identity":"rs-9157131","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}