Human fetal development between 90 and 170 days postmenses.

Area of Science:

• Embryology and Developmental Biology
• Human Anatomy
• Reproductive Medicine

Background:

• Understanding human fetal growth is crucial for clinical practice and research.
• Established reference ranges for fetal parameters are essential for assessing normal development.
• Therapeutic abortion provides a source for studying early-stage human development.

Purpose of the Study:

• To document linear measurements, total weights, and organ weights in a cohort of human fetuses.
• To assess the degree of variation in these parameters within specific gestational age ranges.
• To investigate potential influences of fetal sex and maternal parity on fetal growth metrics.

Main Methods:

• Collection of data from 133 fresh human fetuses following therapeutic abortion.
• Measurements included linear dimensions, total body weight, and individual organ weights.
• Gestational age ranged from 90 to 170 days postmenses.

Main Results:

• Significant variability was observed in linear measurements and body weights among fetuses of the same gestational age.
• Organ weights exhibited particularly notable variation.
• No statistically significant differences were found in the measured parameters between male and female fetuses.
• Maternal parity did not appear to influence fetal growth metrics in this cohort.

Conclusions:

• Human fetal development displays considerable individual variation, particularly in organogenesis.
• Standardized growth charts should account for this inherent variability.
• Fetal sex and maternal parity are not significant determinants of growth within the 90-170 days postmenses range.