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Updated: Aug 4, 2026
12:17
The 4-vessel Sampling Approach to Integrative Studies of Human Placental Physiology In Vivo
Published on: August 2, 2017
Continuing growth and development of the third-trimester human placenta
Placenta
|January 1, 1985
Summary
Human placental growth, measured by weight and nuclear number, does not falter with increasing gestational age. Placental size is appropriate for babies, even those with intrauterine growth retardation.
Area of Science:
- Obstetrics and Gynecology
- Developmental Biology
- Human Placental Biology
Background:
- Previous research suggested potential faltering in human placental weight and nuclear number with advancing gestational age.
- Understanding placental development is crucial for assessing fetal well-being and predicting birth outcomes.
Purpose of the Study:
- To investigate the relationship between gestational age and human placental weight and nuclear number.
- To determine if placental growth parameters differ in cases of intrauterine growth retardation (IUGR).
Main Methods:
- Measurement of placental weight and nuclear number in 219 human placentae.
- Correlation analysis of placental parameters with ascertained gestational age.
- Comparison of placental characteristics in IUGR versus appropriate for gestational age neonates.
Main Results:
- No evidence of faltering in placental weight or nuclear number was observed with increasing gestational age.
- Placentae from infants with IUGR were found to be appropriate in size relative to fetal growth.
- The rate of nuclear number increase in the placenta does not appear to be dependent on gestational age.
Conclusions:
- Human placental growth, in terms of weight and nuclear number, is consistent throughout gestation.
- Placental development is appropriately scaled to fetal growth, even in the presence of IUGR.
- Nuclear proliferation in the placenta is not directly linked to the aging process of the placenta itself.
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