Placental Thickness -To-Fetal Weight Ratio as a Predictor of Adverse Pregnancy Outcome
For patients and families
In plain language
An automatic summary of structured registry data. It is an orientation aid, not a substitute for the official protocol or a physician assessment.
- What is being studied
- This is an observational study: the protocol does not assign a study treatment.
- Who it may be relevant to
- Registry conditions: Placental Thickness, PLACENTA VOLUME. Basic parameters: 20 years — 45 years · Female.
- What needs checking
- Age, condition and sex are only basic indicators. Prior treatment, laboratory values and other mandatory requirements appear in the eligibility criteria below.
- Where it takes place
- Center list to be confirmed — check the primary protocol.
- Next step
- Save the trial, show it to the treating physician, and confirm current recruitment with the study center. Costs, documents and travel →
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Overview
The aim of this study is to evaluate the placental thickness-to-fetal weight ratio as a predictor of adverse pregnancy outcomes.
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.
Primary outcome measures
- The rate of occurrence of adverse pregnancy outcomes, including IUGR, preterm birth, low birth weight, fetal distress, NICU admission, or perinatal mortality [Time frame: From aug 2026 to aug 2029]
Eligibility criteria
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
Criteria are shown verbatim from the registry (in English). Final eligibility is always assessed by the study center.
Healthy volunteers: No
Study design
- Observational model
- Cohort
Study locations
Center list to be confirmed — check the primary protocol.
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 a
Identifiers
NCT: NCT07467148 · P. Thickness to fetal weight