Anti-müllerian hormone in early human development

Area of Science:

• Reproductive Endocrinology
• Developmental Biology
• Fetal Medicine

Background:

• Anti-Müllerian hormone (AMH) is a glycoprotein crucial for male fetal development, produced by Sertoli cells.
• AMH mediates the regression of müllerian ducts in developing male fetuses.

Purpose of the Study:

• To investigate the ontogeny and diagnostic utility of AMH in early human development.
• To assess AMH as a marker for functional testicular tissue and fetal sex determination.

Main Methods:

• Measurement of serum AMH concentrations in male and female fetuses across different gestational ages.
• In situ hybridization to detect AMH transcripts in fetal gonadal tissue.
• Comparison of fetal AMH levels with those in infant boys.

Main Results:

• Detectable AMH was found in male fetal serum (19-30 weeks: 40.5 ng/ml; 30 weeks-term: 28.4 ng/ml), but not in female fetuses.
• AMH levels in late-term male fetuses were lower than in infants (2 months-2 years), indicating sluggish perinatal production.
• AMH transcripts were present in fetal testes from 8 weeks but absent in ovaries and undifferentiated gonads.
• A 46,XX male fetus exhibited AMH levels within the normal male range.

Conclusions:

• AMH is a reliable indicator of functional testicular tissue presence in fetuses.
• AMH measurements can aid in fetal sex diagnosis, especially in cases of sex chromosome abnormalities.