The Journal of Health, Population and Nutrition
Vol. 35, No. 1, 2016, pp. 1-9
Bioline Code: hn16021
Full paper language: English
Document type: Research Article
Document available free of charge
The Journal of Health, Population and Nutrition, Vol. 35, No. 1, 2016, pp. 1-9
© Copyright 2016 - The Journal of Health, Population and Nutrition
A home calendar and recall method of last menstrual period for estimating gestational age in rural Bangladesh: a validation study|
Gernand, Alison D.; Paul, Rina Rani; Ullah, Barkat; Taher, Muhammad A.; Witter, Frank R.; Wu, Lee; Labrique, Alain B.; West Jr., Keith P. & Christian, Parul
Background: The best method of gestational age assessment is by ultrasound in the first trimester; however, this
method is impractical in large field trials in rural areas. Our objective was to assess the validity of gestational age
estimated from prospectively collected date of last menstrual period (LMP) using crown-rump length (CRL)
measured in early pregnancy by ultrasound.
Methods: As part of a large, cluster-randomized, controlled trial in rural Bangladesh, we collected dates of LMP by
recall and as marked on a calendar every 5 weeks in women likely to become pregnant. Among those with a urinetest
confirmed pregnancy, a subset with gestational age of <15 weeks (n = 353) were enrolled for ultrasound
follow-up to measure CRL. We compared interview-assessed LMP with CRL gestational age estimates and
classification of preterm, term, and post-term births.
Results: LMP-based gestational age was higher than CRL by a mean (SD) of 2.8 (10.7) days; differences varied by
maternal education and preterm birth (P < 0.05). Lin’s concordance correlation coefficient was good at ultrasound
[0.63 (95 % CI 0.56, 0.69)] and at birth [0.77 (95 % CI 0.73, 0.81)]. Validity of classifying preterm birth was high but
post-term was lower, with specificity of 96 and 89 % and sensitivity of 86 and 67 %, respectively. Results were
similar by parity.
Conclusions: Prospectively collected LMP provided a valid estimate of gestational age and preterm birth in a rural,
low-income setting and may be a suitable alternative to ultrasound in programmatic settings and large field trials.
Trial registration: ClinicalTrials.gov NCT00860470
Last menstrual period; Ultrasound; Validation; Bangladesh; Gestational age; Crown-rump length
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