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Postnatal developmental changes in the pituitary-ovarian axis in preterm and term infant girls

Tanja Kuiri-Hänninen1, Sanna Kallio, Raija Seuri

  • 1Department of Pediatrics, University of Eastern Finland and Kuopio University Hospital, FI-70211 Kuopio, Finland.

The Journal of Clinical Endocrinology and Metabolism
|September 9, 2011
PubMed

Insights

Preterm and near-term infant girls show a stronger and longer postnatal FSH surge, leading to delayed ovarian development. This suggests a potential explanation for the exaggerated FSH surge in these infants.

Area of Science:

  • Reproductive Endocrinology
  • Pediatric Endocrinology
  • Neonatal Physiology

Background:

  • Postnatal pituitary-testicular activation is understood in infant boys.
  • The ovarian response to pituitary activation in infancy is less clear.

Purpose of the Study:

  • Compare postnatal developmental changes in the pituitary-ovarian axis.
  • Investigate differences between preterm and term infant girls.

Main Methods:

  • Longitudinal follow-up of 63 infant girls (full term, near term, preterm).
  • Monthly assessments from 1 week to 6 months, reexamined at 14 months corrected age.
  • Measured urinary FSH, serum anti-Müllerian hormone (AMH), and ovarian follicle count via ultrasonography.

Main Results:

  • A stronger, more prolonged postnatal FSH surge was observed in near-term (NT) and preterm (PT) girls compared to full-term (FT) girls.
  • Increased folliculogenesis and AMH levels followed the FSH surge in all groups.
  • Follicular development was delayed in NT and PT girls, with decreased FSH correlating to antral follicle appearance and AMH rise.

Conclusions:

  • The postnatal FSH surge transiently stimulates the ovaries in both term and preterm infant girls.
  • Delayed ovarian folliculogenesis, indicated by ultrasonography and low AMH, may explain the exaggerated FSH surge in NT and PT infants.
Abstract

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