Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2007 Sep:21 Suppl 2:50-61.
doi: 10.1111/j.1365-3016.2007.00861.x.

Assessing the quality of last menstrual period date on California birth records

Michelle Pearl  1 , Megan L Wier, Martin Kharrazi
Affiliations

Assessing the quality of last menstrual period date on California birth records

Michelle Pearl et al. Paediatr Perinat Epidemiol. 2007 Sep.

Abstract

Birth certificate last menstrual period (LMP) date is widely used to estimate gestational age in the US. While data quality concerns have been raised, no large population-based study has isolated data quality issues by comparing birth record LMP (Birth LMP) with reliable LMP dates from another source. We assessed LMP data quality in 2002 California singleton livebirth records (n = 515 381) and in a subset of records with linked prenatally collected LMP from California's statewide Prenatal Expanded Alpha-fetoprotein Screening Program (XAFP) (n = 105 936). Missing or incomplete LMP data affected 13% of birth records; 17% of those had complete LMP within XAFP records. Data quality indicators supported XAFP LMP as more accurate than Birth LMP, with a lower prevalence of digit preference, post-term delivery, out-of-range gestational age estimates and implausible birthweight-for-gestational age. The bimodal birthweight distribution evident at 20-31 weeks' gestation based on Birth LMP was nearly absent with XAFP LMP-based gestational age. Approximately 32% of the second birthweight mode was explained by apparent clerical errors in Birth LMP month. Digit preference errors, particularly day 1, were associated with gestational age overestimation. Preterm delivery rates were higher according to Birth (7.6%) vs. XAFP LMP (7.2%). One-fifth of observed preterm and over half of observed post-term births using Birth LMP were not true cases; 15% of true preterm cases were missed. African American or Hispanic, less educated, and publicly or uninsured women were most likely to be misclassified and have large LMP date discrepancies attributable to clerical or digit preference error. The implementation of a revised birth certificate is an opportunity for targeted training and data entry checks that could substantially improve LMP accuracy on birth records.

PubMed Disclaimer

Similar articles

See all similar articles

Cited by

See all "Cited by" articles

Publication types

LinkOut - more resources