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Vaginal Bleeding in an Infant with Extreme Prematurity
Wing Yiu Sarah Poon1, Joanna Yuet Ling Tung1,2
1Department of Paediatrics and Adolescent Medicine, Queen Mary Hospital, The University of Hong Kong, NCB 115, 102 Pokfulam Rd, Pok Fu Lam, Hong Kong.
Insights
Minipuberty in premature infants can cause vaginal bleeding due to exaggerated hormone surges. This benign condition typically resolves on its own without intervention.
Area of Science:
- Pediatric Endocrinology
- Neonatology
- Reproductive Medicine
Background:
- Minipuberty involves transient activation of the hypothalamic-pituitary-gonadal (HPG) axis in early infancy.
- Preterm infants may experience a more pronounced and extended gonadotropin surge compared to full-term infants.
Observation:
- A case of minipuberty presenting with vaginal bleeding at 3 months corrected age in an extremely preterm infant (23+6 weeks gestation).
- Physical examination revealed bilateral breast buds, with hormonal investigations showing pubertal levels of LH, FSH, and estradiol.
Findings:
- The exaggerated gonadotropin surge in this extremely preterm infant led to endometrial maturation and vaginal bleeding.
- Hormonal levels and symptoms resolved spontaneously by 8 months corrected age, indicating a self-limiting process.
Implications:
- This case highlights that exaggerated minipuberty in preterm infants can manifest as vaginal bleeding.
- Pediatricians should recognize this as a benign, self-limiting phenomenon, avoiding unnecessary interventions.
Background:
Minipuberty of infancy refers to the transient activation of the hypothalamic-pituitary-gonadal (HPG) axis during the first few months of life. Studies have documented a more exaggerated and prolonged gonadotropin surge in preterm infants compared with term infants. We present a case of minipuberty presenting with vaginal bleeding at the corrected age of 3 months of life. Case Presentation. A former 23 + 6-week infant presented with intermittent vaginal bleeding in the diaper at the corrected age of 3 months. Physical exam showed bilateral breast buds of 0.5 cm-1 cm with no signs of pubarche. Investigations showed pubertal levels of luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol. As she was impressed to have exaggerated minipuberty due to extreme prematurity, no intervention was given. Repeated hormonal workup at the corrected age of 8 months showed decreasing trend of gonadotropin and estradiol levels. Vaginal bleeding resolved, and breast buds also regressed clinically.
Conclusion:
Our case illustrated that the robust surge of gonadotropin in an ex-premature infant can in fact result in endometrial maturation and present as vaginal bleeding. Though the mechanism of this alteration in the HPG axis in prematurity is not clearly understood, pediatricians should be aware of the benign and self-limiting nature of this phenomenon and avoid unnecessary intervention.
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