Correlation of gestational age assessed by last menstrual period and New Ballard’s Score in pre term babies

Krithika S., Rajanish K. V., Adarsh E.


Background: Gestational age is a critical factor in the management, decision making and follow up of new born infants. Identification of gestational age especially within 48 hours of life is crucial for new born. Since decades attempts have been made to find an alternative measurement for gestational age and birth weight estimation of the newborns. Last menstrual period is an inexpensive method and potentially efficient for calculating gestational age. Objective of this study was to the present study aims to compare the gestational age by New Ballards score with LMP, in pre term babies.

Methods: A total 150 pre term babies who are born to mothers remembering LMP were enrolled for the study group. During the study period new Ballard scoring was done for babies within 48hrs and Gestational age was compared with LMP. The collected data was analyzed by using SAS-6.50 version. Study design a prospective observational study was conducted over a period of one year from January 2018 till December 2018 at Rajarajeswari Medical College and Hospital, Bengaluru, India

Results: The New Ballard score is found to be significantly correlated with GA above 29 weeks (p<0.01). The LMP mean was 35±2.0 weeks. Total 60.6 % of the childbirth is lead to normal vaginal delivery. The analysis shows LMP were found to be strongly correlated with GA (p<0.01).

Conclusions: LMP alone can be reliably used in assessing the gestational age and can be assessed more accurately and be confirmed with new Ballard’s scoring for preterm babies of >29 weeks.


Ballard’s score, GA-gestational age, Last menstrual period, Preterm

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Hutchison D.J Gestational age assessment. Am Family Physician. 1991;43:398-400.

Ballard JL. Simplified score for assessment of fetal maturation of newly born infants. J Pediatr. 1979;95:769-74.

Kurtz AR. Gestationa1 age: what to measure and when. Seminars in Roentgenol. 1990;25:299-308.

Harrison KA. Last menstrual period and, gestational age estimate. Am Family Physician. 1993;47:1710-3.

Koga Y, Fujied K, Matsumoto Y. gestational age assessment in Japanese low birth weight infants. Acta Pediatr Japan. 1994;36:71-4.

Vik T, Vatten L, Markestd T. New Ballard’s assessment of gestational age and agreement with prenatal methods. Am J Perinatol. 1997:369-72.

Gagliardi L, Brambilla C, Bruno R, Martinelli S, Console V. Biased Assessment of Gestational Age at birth when obstetric gestation is known. Arch Dis Child. 1993;68:32-4.

Smith LN, Dayal VH, Monga M. Prior Knowledge of Obstetric Gestational Age and Possible Bias of Ballard Score. Obstetr Gynecol. 1999;93:712-4.

Opara P. Gestational age assessment in the newborn-a review. Internet J Pediatr Neonatol. 2009;12(2):1-9.

Kaur P, Desai DA, Taraiya A. A study to evaluate accuracy of gestational age, comparing conventional method against duration of intermenstrual interval consideration. Int J Reprod Contracept Obstet Gynecol. 2015;4(5):1291-5.