Assessment of placental thickness as a predictor of gestational age and fetal weight in second and third trimester of pregnancy
Keywords:Gestational age, Fetal weight, Placenta thickness, Fetal biometry
Background: Estimation of precise gestational age as well as fetal weight is important and is usually done by ultrasound assessment of fetal biometry. Recently estimation of placental thickness as a marker of fetal maturity as well as fetal weight has become a topic interest amongst obstetricians because of the accuracy with which placental thickness can be used for estimation of gestational age. We undertook this observational study to find out whether placental thickness can be used for estimation of gestational age and fetal weight in healthy singleton pregnancies.
Methods: This was a prospective observational study in which 210 patients in second and third trimester of pregnancy who has undergone antenatal ultrasound examination were included on the basis of a predefined inclusion and exclusion criteria. First gestational age estimation was done using fetal biometry (head circumference, biparietal diameter, abdominal circumference and femur length). Placental thickness was measured at the level of cord insertion. Correlation between placental thickness and gestational age as well as fetal weight as determined by biometry was analyzed by pearsons coefficient. P value less than 0.05 was taken as statistically significant.
Results: Mean age of studied cases found to be 24.62±4.12 years. Mean gestational age of the studied cases was found to be 28.19±6.90 weeks. The most common location of placenta was anterior which was seen in 99 (47.14%) patients followed by posterior (32.38%) and fundal (10.95%). Analysis of mean placental thickness in studied cases showed that at 12 weeks of gestation the mean placental thickness was 12.96 mm. Mean placental thickness at 37 weeks found to be 36.82 mm and this value was determined to be cut-off value for differentiating between full term and preterm gestation. There was strong positive correlation between placental thickness and gestational age between 12-38 weeks. Similarly positive correlation also existed between placental thickness and gestational age between 14-37 weeks.
Conclusions: Placental thickness can be used for estimation of gestational age as well as fetal weight in cases where fetal biometry can not be entirely relied upon.
Fadl S, Moshiri M, Fligner CL, Katz DS, Dighe M. Placental Imaging: Normal Appearance with Review of Pathologic Findings. Radiographics. 2017;37(3):979-98.
Mathai BM, Singla SC, Nittala PP, Chakravarti RJ, Toppo JN. Placental thickness: its correlation with ultrasonographic gestational age in normal and intrauterine growth-retarded pregnancies in the late second and third trimester. J Obstet Gynaecol India. 2013;63(4):230-3.
García-Basteiro AL, Quintó L, Macete E, Bardají A, González R, Nhacolo A et al. Infant mortality and morbidity associated with preterm and small-for-gestational-age births in Southern Mozambique: A retrospective cohort study. PLoS One. 2017;12(2):e0172533.
Bamfo JE, Odibo AO. Diagnosis and management of fetal growth restriction. J Pregnancy. 2011;2011:640715.
Wapner RJ. Invasive prenatal diagnostic techniques. Semin Perinatol. 2005;29(6):401-4.
Skupski DW, Owen J, Kim S, Fuchs KM, Albert PS, Grantz KL. Eunice Kennedy Shriver National Institute of Child Health and Human Development Fetal Growth Studies. Estimating Gestational Age From Ultrasound Fetal Biometrics. Obstet Gynecol. 2017;130(2):433-41.
Dudley NJ. The management of error in ultrasound fetal growth monitoring. Ultrasound. 2021;29(1):4-9.
Galal M, Symonds I, Murray H, Petraglia F, Smith R. Postterm pregnancy. Facts Views Vis Obgyn. 2012;4(3):175-87.
Agwuna KK, Eze CU, Ukoha PO, Umeh UA. Relationship between Sonographic Placental Thickness and Gestational Age in Normal Singleton Fetuses in Enugu, Southeast Nigeria. Ann Med Health Sci Res. 2016;6(6):335-40.
McIntire DD, Bloom SL, Casey BM, Leveno KJ. Birth weight in relation to morbidity and mortality among newborn infants. N Engl J Med. 1999;340(16):1234-8.
Milner J, Arezina J. The accuracy of ultrasound estimation of fetal weight in comparison to birth weight: A systematic review. Ultrasound. 2018;26(1):32-41.
Humadi EH, Zghair MA, Kudhire NA. The accuracy of placental thickness in estimation of gestational age during late third trimester-A single centre cross sectional study. J Pak Med Assoc. 2021;71(8)(12):S93-6.
Erkamp JS, Voerman E, Steegers EAP, Mulders AGMGJ, Reiss IKM, Duijts L, Jaddoe VWV, Gaillard R. Second and third trimester fetal ultrasound population screening for risks of preterm birth and small-size and large-size for gestational age at birth: a population-based prospective cohort study. BMC Med. 2020;18(1):63.
Njeze NR, Ogbochukwu JO, Chinawa JM. Correlation of ultrasound placental diameter and thickness with gestational age. Pak J Med Sci. 2020;36(5):1058-62.
Karthikeyan T, Subramaniam RK, Johnson W, Prabhu K. Placental thickness and its correlation to gestational age and foetal growth parameters-a cross sectional ultrasonographic study. J Clin Diagn Res. 2012;6(10):1732-5.
Keshavarz E, Motevasselian M, Amirnazeri B, Bahramzadeh S, Mohammadkhani H, Mehrjardi Z et al. Gestational age-specific reference values of placental thickness in normal pregnant women. Women Health. 2019;59(7):718-29.
Azagidi AS, Ibitoye BO, Makinde ON, Idowu BM, Aderibigbe AS. Fetal Gestational Age Determination using Ultrasound Placental Thickness. J Med Ultrasound. 2019;28(1):17-23.
Afrakhteh M, Moeini A, Taheri MS, Haghighatkhah HR. Correlation between placental thickness in the second and third trimester and fetal weight. Rev Bras Ginecol Obstet. 2013;35(7):317-22.
Hamidi OP, Hameroff A, Kunselman A, Curtin WM, Sinha R, Ural SH. Placental thickness on ultrasound and neonatal birthweight. J Perinat Med. 2019;47(3):331-4.
Salafia CM, Zhang J, Charles AK. Placental characteristics and birthweight. Paediatr Perinat Epidemiol. 2008;22:229-9.