Investigating the relationship between ultrasound criteria in determining the age of postdate pregnancy


Postdate pregnancy is a pregnancy that pasts more than forty weeks. This can be dangerous for the mother, fetus, and newborn. By knowing the most appropriate ultrasound criteria in predicting the probability of postdate pregnancy, its complications can be reduced by taking timely measures. Therefore, the present study was conducted with the aim of determining the relationship between ultrasound criteria in determining the age of postdate fetuses. This cross-sectional study (descriptive-analytical type) was done in Kermanshah Imam Reza Hospital on 33 pregnant women that, according to LMP and first-trimester ultrasound, pregnancy age was more than 40 weeks. Gestational age was calculated by various ultrasound criteria, including head circumference measurement (HC), Abdominal Circumference (AC), Biparietal Diameter (BPD), femur length (FL), and Transcerebellar Diameter (TCD). The findings were compared with calculated age by LMP. Data were analyzed by SPSS16 software. Correlation rate of pregnancy age based on LMP with FL (R=0.576, P<0.001), AC (R=0.208, P=0.245), BPD (R= -0.200, P=0.264), HC (R= -0.211, P=0.238) and TCD were (R=0.111, P=0.538). The pregnancy age correlation rate based on LMP with ultrasound criteria in general was (R=0.140, P=0.436). There was a direct relationship between gestational age based on LMP with FL, AC, TCD and inversely related to BPD and HC. Among the sonographic criteria, only the FL criterion was significantly correlated with LMP. In general, the correlation between gestational age based on LMP and ultrasound was not statistically significant.

1. Dilmen G, Turhan NO, Toppare MF, Seckin N, Oztark M, Goksin E. Scapula length measurement for assessment of fetal growth and development. Ultrasound Med Biol 1995;21:139-42.
2. Thorsell M, Kaijser M, Almström H, Andolf E. Expected day of delivery from ultrasound dating versus last menstrual period: obstetric outcome when dates mismatch. BJOG 2008;115:585-9.
3. Norwitz ER, Snegovskikh VV, Caughey AB. Prolonged pregnancy: when should we intervene? Clin Obstet Gynecol 2007;50:547-57.
4. Heimstad R, Skogvoll E, Mattsson LA, Johansen OJ, Eik-Nes SH, Salvesen KA. Induction of labor or serial antenatal fetal monitoring in postterm pregnancy: a randomized controlled trial. Obstet Gynecol 2007;109:609-17.
5. Martin Ja, Hamilton be, Sutton Pd, Ventura SJ, Menacker F, Kirmeyer S, et al. births: final data for 2005. Natl Vital Stat Rep 2007;56:1-103.
6. Collins JW, Schulte NF, George L, Drolet A. Postterm delivery among african americans, Mexican americans and Whites in Chicago. Ethn Dis 2001;11:181-7.
7. Caughey AB, Stotland NE, Washington AE, et al. Who is at risk for prolonged and postterm pregnancy. Am J Obstet Gynecol 2009;200:683.e1-5.
8. Alfirevic Z, Walkinshaw SA. Management of post-term pregnancy: to induce or not? Br J Hosp Med 1994;52:218-21.
9. Allen VM, O’Connell CM, Farrell SA, Baskett TF. Economic implications of method of delivery. Am J Obstst Gynecol 2005;193:192-7.
10. Mogren I, Stenlund H, Hogberg U. Recurrence of prolonged pregnancy. Int J Epidemiol 1999; 28:253-7.
11. Olesen AW, Basso O, Olsen J. An estimate of the tendency to repeat postterm delivery. Epidemiology 1999;10:468-9.
12. Divon MY, Ferber A, Nisell H, Westgren M. Male gender predisposes to prolongation of pregnancy. Am J Obstet Gynecol 2002;187:1081-3.
13. Usha Kiran TS, Hemmadi S, Bethel J, Evans J. Outcome of pregnancy in a woman with an increased body mass index. BJOG 2005;112:768-72.
14. Stotland NE, Washington AE, Caughey AB. Pre-pregnancy body mass index and length of gestation at term. Am J Obstet Gynecol 2007;197:378.e1-5.
15. Laursen M, Bille C, Olesen AW, Hjelmborg J, Skytthe A, Christensen K. Genetic influence on prolonged gestation: a population-based danish twin study. Am J Obstet Gynecol 2004;190:489-94.
16. Crowley P. Interventions for preventing or improving the outcome of delivery at or beyond term (Cochrane review). In the Cochrane library. Chicester, uK: JohnWiley & Sons, ltd, 2004.
17. Neilson JP. Ultrasound for fetal assessment in early pregnancy. Cochrane database Syst Rev 2000;2:Cd000182.
18. Alexander JM, Mcintire DD, Leveno KJ. Forty weeks and beyond: pregnancy outcomes by week of gestation. Obstet Gynecol 2000;96:291-4.
19. Rand L, Robinson JN, Economy Ke, Norwitz ER. Post-term induction of labor revisited. Obstet Gynecol 2000;96:779-83.
20. Campbell MK, Ostbye T, Irgens LM. Post-term birth: risk factors and outcomes in a 10-year cohort of norwegian births. Obstet Gynecol 1997;89:543-8.
21. Treger M, Hallak M, Silberstein T, Friger M, Katz M, Mazor M. Post-term pregnancy: should induction of labor be considered before 42 weeks? J Matern Fetal neonatal Med 2002;11:50-3.
22. Mandruzzato G, Alfirevic Z, Chervenak F, Gruenebaum A, Heimstad R, Heinonen S, et al. Guidelines for the management of postterm pregnancy. J Perinat Med 2010;38:111-9.
23. Walker N, Fischer-Walker C, Bryce J, Bahl R, Cousens S. Standards for CHERG reviews of intervention effects on child survival. Int J Epidemiol 2010;39:i21-31.
24. Olesen AW, Basso O, Olsen J. Risk of recurrence of prolonged pregnancy. BMJ 2003;326:476.
25. Olesen AW, Westergaard JG, Olsen J. Perinatal and maternal complications related to postterm delivery: a national register-based study, 1978-1993. Am J Obstet Gynecol 2003;189:222-7.
26. Caughey AB, Stotland NE, Washington AE, Escobar GJ. Maternal obstetric complications of pregnancy are associated with increasing gestational age at term. Am J Obstet Gynecol 2007;196:155.e1-6
27. Sarris I, Ioannou C, Chamberlain P, Ohuma E, Roseman F, Hoch L. Intra- and interobserver variability in fetal ultrasound measurements. Ultrasound Obstet Gynecol 2012;39:266-73.
28. Okland I. Biases in second trimester ultrasound dating related to prediction models and fetal measurements [PhD dissertation]. Norway: University of Science and Technology Faculty of Medicine.; 2012.
29. Priestly Shan B. Madheswaran M. Revised Estimates of Ultrasonographic Markers forGestational Age Assessment of Singleton Pregnancies among Indian Population. Int J Adv Res Sci Eng Technol 2010;17:1-12.
30. ACOG Committee on Practice Bulletins-Obstetrics. ACOG Practice Bulletin. Clinical management guidelines for obstetricians-gynecologists. Number 55, September 2004 (replaces practice pattern number 6, October 1997). Management of Postterm Pregnancy. Obstet Gynecol 2004;104:639-46.
31. Robinson HP. Sonar measurement of fetal crown-rump length as means of assessing maturity in first trimester of pregnancy. Br Med J 1973;4:28-31.
32. Napolitano R, Dhami J, Ohuma EO, Ioannou C, Conde-Agudelo A, Kennedy SH, et al. Pregnancy dating by fetal crown-rump length: a systematic review of charts. BJOG 2014;121:556-65.
33. Kimberly B , Ken L, Diagnostic Imaging Committee. Determination of Gestational Age by Ultrasound. J Obstet Gynaecol Can 2014;36:171-81.
34. Butt K, Lim K; Society of Obstetricians and Gynaecologists of Canada. Determination of gestational age by ultrasound. J Obstet Gynaecol Can 2014;36:171-83.
35. Fahimi F. Estimation of Gestational Age According to Sonography Parameters, Comparing Mono - and Multivariate Models. Hamedan Med Univ J 2004;11:24-7.
36. Sahebghalam H, Panahi GH, Dadgar S, Afzali N, Shaban M. The Comparison of the Diagnostic Value of Fetal Foot length Measurement with the length of Femur and Fetal biparietal Diameter in Determining the Gestational Age. Iran Obstet Gynecol J 2009;11:9-13.
37. Sahebghalam H, Dadgar S, Sadri MB. Determine the gestational age and identify the term embryos by measuring the diameters of the colon by ultrasound. IJOGI 2015;18:1-7
38. Farshchian N, Fakheri T, Rezaei M, Ebrahimi HR. Comparison of diagnostic value of fetal cerebellar hemisphere circumference measurement and routine ultrasonography parameters for determination of the gestational age. Sci J Kurdistan Univ Med Sci 2014;19:51-7.
39. Bennett Ka, Crane JM, O’Shea P, Lacelle J, Hutchens D, Copel JA. First trimester ultrasound screening is effective in reducing postterm labor induction rates: a randomized controlled trial. Am J Obstet Gynecol 2004;190:1077-81.
40. Caughey AB, Nicholson JM, Washington AE. First versus second trimester ultrasound: the effect on pregnancy dating and perinatal outcomes. Am J Obstet Gynecol 2008;198:703.e1-703.e6.
41. Papageorghiou AT, Kemp B, Stones W, Ohuma EO, Kennedy SH .Ultrasound-based gestational-age estimation in late pregnancy. Ultrasound Obstet Gynecol 2016;48:719-26.
42. Behdani R, Beigi A, Mobaraki N. First trimester sonography: effective in reducing of post term pregnancy rate. Tehran Univ Med J 2008;66:123-6.
IssueVol 59, No 4 (2021) QRcode
Postdate pregnancy Sonographic criteria in determining gestational age Last menstrual period (LMP)

Rights and permissions
Creative Commons License This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License.
How to Cite
Farshchian N. Investigating the relationship between ultrasound criteria in determining the age of postdate pregnancy. Acta Med Iran. 59(4):217-222.