Prenatal ages and stages-measures and errors.

Area of Science:

• Obstetrics and Gynecology
• Embryology
• Prenatal Development

Background:

• The term "gestational age" is ambiguously used, often conflated with menstrual, postovulatory, or postfertilizational age.
• While menstrual dating is useful, it is a misnomer as prenatal age spans from fertilization to birth.
• The term "stage" has a defined embryological meaning and should not be used for age or length estimations.

Purpose of the Study:

• To clarify the confusion surrounding prenatal age terminology.
• To advocate for the abandonment of the ambiguous term "gestational age".
• To promote precise definitions for embryonic and fetal age.

Main Methods:

• Assessment of embryonic age using 23 internationally recognized morphological stages.
• Utilizing measurements for fetal period age assessment due to the absence of a morphological staging system.
• Critiquing and proposing alternatives for biometric measurements like crown-rump length (CRL).

Main Results:

• Embryonic age is best determined by morphological stages.
• Fetal age assessment relies on measurements, with "greatest length" (GL) proposed as a replacement for "crown-rump length" (CRL).
• The term "gestational age" is deemed unnecessary and superfluous.

Conclusions:

• Abandoning the term "gestational age" resolves confusion in prenatal age assessment.
• Implementing precise terminology for embryonic and fetal age enhances clarity in obstetrics and embryology.
• Standardizing biometric measurements like greatest length (GL) improves accuracy in prenatal assessments.