Menstrual Bleeding as a Manifestation of Mini-Puberty of Infancy in Severe Prematurity

In Memory of Ivo Brosens: Reflections on the Pathophysiology of Neonatal Uterine Bleeding

BACKGROUND

The occurrence of vaginal bleeding in early neonatal life has been observed for centuries and was considered a consequence of the sudden drop in circulating hormones following birth. As such, neonatal uterine bleeding was dismissed as having no clinical significance. Interest in the phenomenon was renewed when a new theory suggested a link between neonatal uterine bleeding (NUB) and accelerated endometrial maturation. This theory was based on the observation of a higher incidence of NUB in babies born post-term or after pregnancies complicated by intrauterine growth restriction, preeclampsia, or blood group incompatibility.

OBJECTIVE

The objective of this study was to review of available evidence on the pathogenesis of NUB.

METHOD

Review of available literature using Medline search (August 2022, no limit on start date or language) to identify articles that may link NUB with features of the uterus and/or endometrium.

OUTCOME

The fetal endometrial responses differ from that of the adult. In the fetus, the endometrium features progestogenic response only in a minority of cases. The endometrium in most newborn girls does not exhibit secretory or decidual changes which indicate lack of progesterone response. Most newborn girls do not have visible bleeding. Animal studies linked exogenous progestogen exposure during the period of organogenesis to poor endometrial gland development, progesterone resistance, and to alterations of reproductive performance. Although the fetal endometrium may not exhibit a full proliferative response, it is clearly sensitive to circulating estrogens. Molecular mechanisms involved in NUB may include "ontogenetic progesterone resistance."

CONCLUSION AND OUTLOOK

Endometrial development and its response to withdrawal of hormones at birth varies and may be affected by intrauterine stressors and gestational age. Factors that affect endometrial development during fetal life and in preterm neonates can have implications on future reproductive performance.

Exaggerated mini-puberty in a preterm girl: a case report and review of literature

OBJECTIVES

Mini-puberty is the physiological and transient activation of the hypothalamic-pituitary-gonadal axis occurring during the first months after birth. In preterm infants, the hormonal surge is more pronounced and longer-lasting than in at-term-peers. To date, only few cases of vaginal bleeding in the setting of an exaggerated mini-puberty have been reported.

CASE PRESENTATION

At the corrected age of 3 months, an ex-very-preterm girl presented with breast enlargement and recurrent vaginal bleeding. A remarkable increase in gonadotropins and estradiol levels was detected, while pelvic ultrasound highlighted a large right ovarian cyst. As brain and pituitary MRI showed negative findings, an exaggerated mini-puberty was suspected and no additional investigations were undertaken. The subsequent progressive regression of clinical, biochemical and sonographic findings confirmed the diagnosis.

CONCLUSIONS

Although exaggerated mini-puberty of infancy in ex-preterm girls is a rare event, it is important to raise knowledge of this para-physiological condition in order to avoid unnecessary investigations and treatment.

Exacerbated mini-puberty of infancy in an ex-extreme preterm girl

Vaginal bleeding can occur shortly after delivery in 3%-5% of newborns as a consequence of placental hormone withdrawal . Although usually benign, its differential diagnosis includes central precocious puberty, tumours and other pathological conditions. A girl born at 26 weeks of gestation presented with five episodes of vaginal bleeding, each lasting less than a week, initiated at 4 months of age. Luteinising hormone and oestradiol levels were in the pubertal range. Later, she exhibited breast development, with no other pubertal signs. An ultrasonography test revealed an impregnated endometrium and a right ovarian cyst with 43 mm of diameter. A cranioencephalic MRI was unremarkable. Clinicians adopted expectant management and there was clinical, hormonal and radiological resolution in 3 months. The spontaneous resolution suggested mini-puberty of infancy. This is usually an asymptomatic condition, but to date, four cases of an exacerbated form in extremepremature infants have been reported. Long-term follow-up data are missing.A girl born at 26 weeks of gestation presented with five episodes of vaginal bleeding, each lasting less than a week, initiated at 4 months of age. Luteinising hormone and oestradiol levels were in the pubertal range. Later, she exhibited breast development, with no other pubertal signs. An ultrasonography test revealed an impregnated endometrium and a right ovarian cyst with 43 mm of diameter. A cranioencephalic MRI was unremarkable. Clinicians adopted expectant management and there was clinical, hormonal and radiological resolution in 3 months. The spontaneous resolution suggested mini-puberty of infancy. This is usually an asymptomatic condition, but to date, four cases of an exacerbated form in extremepremature infants have been reported. Long-term follow-up data are missing.

An 11-month-old girl with central precocious puberty caused by hypothalamic hamartoma

Central precocious puberty (CPP) is caused by premature activation of the hypothalamic-gonadal axis, and must be treated adequately. In particular, CPP that occurs at a relatively young age or in boys is likely to be caused by an organic lesion. Hypothalamic hamartoma (HH) is the most common organic cause of CPP. The present case report describes an 11-month-old female infant who presented with vaginal bleeding and rapidly progressive secondary sex characteristics from the age of 6 months. She was diagnosed with CPP following the detection of HH via magnetic resonance imaging. The infant girl was successfully treated with gonadotropin-releasing hormone agonist. After 6 months, her breast had regressed and clinical and radiological follow-up demonstrated stable findings with no evidence of tumor growth or secondary sexual characteristics until the fourth year after the initiation of treatment. This patient is the one of the youngest infants presenting with CPP and HH in Korea; treatment was successful over a relatively long follow-up period.