Placental Thickness -To-Fetal Weight Ratio as a Predictor of Adverse Pregnancy Outcome

The aim of this study is to evaluate the placental thickness-to-fetal weight ratio as a predictor of adverse pregnancy outcomes.

Study Overview

• Status: Not yet recruiting
• Conditions: PLACENTA VOLUME; Placental Thickness

Detailed Description

The placenta is a vital organ that ensures normal fetal growth and development throughout pregnancy by mediating the exchange of oxygen, nutrients, waste products, and essential hormones between the mother and the fetus (1). Any structural or functional abnormality of the placenta can adversely affect fetal growth and pregnancy outcome, highlighting the importance of placental assessment in antenatal care (2).

Adverse pregnancy outcomes, including intrauterine growth restriction (IUGR), preterm birth, low birth weight, preeclampsia, fetal distress, and perinatal mortality, remain major contributors to maternal and neonatal morbidity and mortality worldwide. Early identification of high-risk pregnancies allows timely interventions, closer surveillance, and improved perinatal outcomes (3). However, advances in ultrasonography and antenatal care, reliable, non-invasive, and easily measurable predictors of adverse outcomes are still limited (4).

Ultrasonographic evaluation of placental morphology has emerged as a practical, non-invasive, and widely accessible method to assess placental health. Among the various parameters, placental thickness reflects placental growth, maturation, and potentially its functional capacity, correlating with gestational age and fetal weight in normal pregnancies. Abnormal placental thickness either decreased or increased has been associated with maternal and fetal pathological conditions (5).

A thin placenta is frequently linked to preeclampsia, IUGR, and chorioamnionitis, whereas a thick placenta defined as more than 3 cm before 20 weeks of gestation and greater than 5 cm at term is observed in Rh-negative pregnancies, gestational diabetes mellitus, and intrauterine infections, particularly primary maternal cytomegalovirus infection (6). Placentomegaly may also be associated with fetal anemia or hromosomal abnormalities such as triploidy, and may result from inflammation, edema, or compensatory hypertrophy secondary to placental insufficiency (7).

Maternal disorders often affect both the fetus and the placenta, making abnormal placental growth a potential marker for impaired fetal growth and adverse neonatal outcomes. Nevertheless, the predictive value of placental thickness alone remains uncertain (8).

Given its simplicity, reproducibility, and cost-effectiveness, ultrasonographic measurement of placental thickness and particularly the placental thickness-to-fetal weight ratio may provide a valuable tool for early detection of high-risk pregnancies. This could allow obstetricians to implement timely interventions, optimize delivery planning, and improve maternal and neonatal outcomes (9). Therefore, this study aims to evaluate the placental thickness-to-fetal weight ratio as a predictor of adverse pregnancy outcomes.

• Study Type: Observational
• Enrollment (Estimated): 70

Contacts and Locations

• Study Contact: Name: Radia Atef Elzokm, Resident doctor; Phone Number: 01202170497; Email: saraatef52222@gmail.com
• Study Contact Backup: Name: Ahmed Mohamed Abbas, Professor; Phone Number: 01003385183; Email: Aahmedabbas@aun.edu.eg

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult
• Accepts Healthy Volunteers: No

• Sampling Method: Non-Probability Sample

Study Population

Hospital

Description

Inclusion Criteria:

• a. Inclusion criteria: Singleton pregnancy. Gestational age between 28-38 weeks. Mothers willing to participate and provide informed consent.

Exclusion Criteria:

• Multiple pregnancies (twins, triplets,etc.) Known congenital fetal anomalies Maternal chronic medical conditions affecting fetal growth (e.g pre-existing diabetes, hypertension, renal disease) Intrauterine fetal demise Inability or refusal to provide informed consent

Study Plan

How is the study designed?

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
The rate of occurrence of adverse pregnancy outcomes, including IUGR, preterm birth, low birth weight, fetal distress, NICU admission, or perinatal mortality	Correlation of placental thickness-to-fetal weight ratio with individual adverse pregnancy outcomes	From aug 2026 to aug 2029

Collaborators and Investigators

• Sponsor: Radia Atef Elzokm

Publications and helpful links

General Publications

• 1.Burton GJ and Jauniaux E. The human placenta: new perspectives on its formation and function during early pregnancy. Proc Biol Sci. 2023;290(13):202-8. 2. Aye IL, Tong S, Charnock-Jones DS and Smith GC. The human placenta and its role in reproductive outcomes revisited. Physiol Rev. 2025;12(2):25-30. 3. Patel SY, Akileswaran C and Basu S. Early detection of high risk pregnancies using clinical and social data to improve health outcomes. npj Digit Public Health. 2026;10(1):3-10. 4. Wang X, Xiao F and Li J. Intrapartum ultrasound monitoring in second-stage Labor: Impact on delivery outcomes. J Radiat Res Appl Sci. 2025;18(4):105-10. 5. Farahbod F, Zarean E, Khanjani S, Moezzi M, Mohammadizadeh F and Shabanian S. Relationship between placental thickness, grading, and heterogeneity in fetal growth restriction in the third trimester of pregnancy by ultrasonography and pathology tests and their relationship with estimated fetal weight and neonatal outcome. Immunopathol Persa. 2023;10(2):39471-6. 6. Li H, Cheng W, Wen J, Peng J, Wu S, Zhao Y, et al. Clinical analysis of prophylactic uterine artery embolization combined with double balloon catheter for second-trimester pregnancy termination in cases of complete placenta previa: A retrospective study. Medicine. 2023;102(47):362-9. 7. Redline RW, Roberts DJ, Parast MM, Ernst LM, Morgan TK, Greene MF, et al. Placental pathology is necessary to understand common pregnancy complications and achieve an improved taxonomy of obstetrical disease. Am J Obstet Gynecol. 2023;228(2):187-202. 8. Manna C, Lacconi V, Rizzo G, De Lorenzo A and Massimiani M. Placental dysfunction in assisted reproductive pregnancies: perinatal, neonatal and adult life outcomes. Int J Mol Sci. 2022;23(2):659-62. 9. Chow LY, Williams EE, Patel D-S and Battersby C. Perinatal optimisation: the role of the multi-disciplinary team. OB-GYN 2025;22(1):25-30. 10. Lwanga SK, Lemeshow S. Sample size determination in health studies: a practical manual. Geneva: World H

Study record dates

Study Major Dates

• Study Start (Estimated): August 1, 2026
• Primary Completion (Estimated): August 1, 2029
• Study Completion (Estimated): December 1, 2029

Study Registration Dates

• First Submitted: March 8, 2026
• First Submitted That Met QC Criteria: March 8, 2026
• First Posted (Actual): March 12, 2026

Study Record Updates

• Last Update Posted (Actual): March 12, 2026
• Last Update Submitted That Met QC Criteria: March 8, 2026
• Last Verified: March 1, 2026

More Information

Terms related to this study

• Other Study ID Numbers: P. Thickness to fetal weight

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No