Lemon Sign: The Diagnostic Indicator for Spina Bifida

Year : 2026 | Volume : 04 | Issue : 01 | Page : 1 6
    By

    Regina P.F.,

  1. Professor, Department of Obstetrics and Gynecological Nursing, PK Das College of Nursing, P.O. Panayur, Ottapalam, Palakkad, Kerala, India

Abstract

The “lemon sign” is a distinctive ultrasonographic finding that serves as a diagnostic indicator for spina bifida, a congenital neural tube defect characterized by incomplete closure of the spinal cord. This sign is observed in fetal imaging and is considered an early and reliable marker for detecting spina bifida, particularly when combined with other prenatal diagnostic tools such as the “banana sign.” The lemon sign is characterized by a flattened, concave appearance of the fetal skull, which occurs due to the herniation of the cerebellum and the posterior displacement of the brain. This deformation is a result of the loss of normal intracranial pressure, commonly associated with spina bifida. The identification of the lemon sign during routine fetal ultrasound can significantly aid in early diagnosis, allowing for timely intervention and management decisions. Prenatal diagnosis using ultrasound plays a crucial role in the management of spina bifida, as it enables healthcare providers to offer appropriate counselling, surgical intervention options, and postnatal care planning. This article explores the pathophysiology, clinical significance, and diagnostic accuracy of the lemon sign in detecting spina bifida, providing an overview of how this marker contributes to the diagnosis and subsequent treatment strategies.

Keywords: Lemon sign, spina bifida, prenatal diagnosis, fetal ultrasound, neural tube defect

[This article belongs to International Journal of Midwifery Nursing And Practices ]

How to cite this article:
Regina P.F.. Lemon Sign: The Diagnostic Indicator for Spina Bifida. International Journal of Midwifery Nursing And Practices. 2026; 04(01):1-6.
How to cite this URL:
Regina P.F.. Lemon Sign: The Diagnostic Indicator for Spina Bifida. International Journal of Midwifery Nursing And Practices. 2026; 04(01):1-6. Available from: https://journals.stmjournals.com/ijmnp/article=2026/view=247387


References

  1. Zaganjor I, Sekkarie A, Tsang BL, Williams J, Razzaghi H, Mulinare J, et al. Describing the prevalence of neural tube defects worldwide: A systematic literature review. PLoS One. 2016;11:e0151586. doi:10.1371/journal.pone.0151586. PMID: 27064786; PMCID: PMC4827875.
  2. Sorri G, Mesfin E. Patterns of neural tube defects at two teaching hospitals in Addis Ababa, Ethiopia: A three-year retrospective study. Ethiop Med J. 2015;53:119–126. PMID: 26677521.
  3. Taye M, Afework M, Fantaye W, Diro E, Worku A. Magnitude of birth defects in central and northwest Ethiopia from 2010–2014: A descriptive retrospective study. PLoS One. 2016;11:e0161998. doi:10.1371/journal.pone.0161998. PMID: 27706169; PMCID: PMC5051902.
  4. Taye M, Afework M, Fantaye W, Diro E, Worku A. Congenital anomalies prevalence in Addis Ababa and the Amhara Region, Ethiopia: A descriptive cross-sectional study. BMC Pediatr. 2019;19:234. doi:10.1186/s12887-019-1596-2. PMID: 31296186.
  5. Gedefaw A, Teklu S, Tadesse BT. Magnitude of neural tube defects and associated risk factors at three teaching hospitals in Addis Ababa, Ethiopia. Biomed Res Int. 2018;2018:4829023. doi:10.1155/2018/4829023. PMID: 29713643; PMCID: PMC5866884.
  6. Getahun S, Masresha S, Zenebe E, Laeke T, Tirsit A. Four-year treatment outcomes of children operated for neural tube defect in Addis Ababa, Ethiopia: A retrospective study. World Neurosurg. 2021;148:e695–e702. doi:10.1016/j.wneu.2021.01.098. PMID: 33540093.
  7. Kar A. Birth defects reporting and surveillance in India: A narrative review. J Community Genet. 2025;16:5–14. doi:10.1007/s12687-024-00760-5. PMID: 39652147; PMCID: PMC11950570.
  8. Mashuda F, Zuechner A, Chalya PL, Kidenya BR, Manyama M. Pattern and factors associated with congenital anomalies among young infants admitted at Bugando Medical Centre, Mwanza, Tanzania. BMC Res Notes. 2014;7:195. doi:10.1186/1756-0500-7-195.
  9. Eke CB, Uche EO, Chinawa JM, Obi IE, Obu HA, Ibekwe RC. Epidemiology of congenital anomalies of the central nervous system in children in Enugu, Nigeria: A retrospective study. Ann Afr Med. 2016;15(3):126–132. doi:10.4103/1596-3519.188892.
  10. Obiekwu AL, Mbadugha CJ, Anetekhai CJ, Isife NG, Kotoye CO. Self-reported compliance with routine prenatal medications by pregnant women in a tertiary hospital in Enugu State, Nigeria. Eur J Midwifery. 2020;4:49. doi:10.18332/ejm/130595.
  11. Van den Hof MC, Nicolaides KH, Campbell J, Campbell S. Evaluation of the lemon and banana signs in one hundred thirty fetuses with open spina bifida. Am J Obstet Gynecol. 1990;162:322–327. doi:10.1016/0002-9378(90)90378-K. PMID: 2178424.

Regular Issue Subscription Review Article
Volume 04
Issue 01
Received 01/03/2026
Accepted 10/04/2026
Published 26/04/2026
Publication Time 56 Days


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