Residency · Residency · Obstetrics Gynecology

Pediatric and Adolescent Gynecology

Introduction

Pediatric and adolescent gynecology encompasses a broad spectrum of conditions unique to the prepubertal and pubertal female patient. Understanding normal developmental milestones is essential for identifying pathology. The approach to examination, diagnosis, and management differs significantly from adult gynecology, requiring specialized communication skills and clinical techniques.

Developmental Anatomy and Physiology

Prepubertal Anatomy

In prepubertal girls, the vulvar skin is thin, unestrogenized, and susceptible to irritation. The labia minora are small, and the hymen is thin and translucent. The vaginal pH is neutral, ranging from 6.5 to 7.5, due to the absence of estrogen-stimulated lactobacilli. The prepubertal uterus has a cervix-to-fundus ratio of approximately 2:1, which reverses to 1:2 after puberty as the fundus grows under hormonal stimulation. Ovarian volume is typically less than 1 mL before thelarche and increases to 2 to 10 mL during adolescence.

Puberty and Tanner Staging

Thelarche, or breast budding, is the first sign of puberty in 85% of girls, occurring at a mean age of 9.5 to 10 years. Adrenarche, driven by adrenal androgens (DHEA-S), leads to the development of pubic and axillary hair. Menarche occurs approximately 2 to 2.5 years after thelarche, at a mean age of 12.4 years. Tanner staging classifies breast development (B1 through B5) and pubic hair development (PH1 through PH5) independently.

<image>Tanner stages of female breast and pubic hair development from prepubertal (Stage 1) through adult (Stage 5), with anatomical illustrations showing progressive changes</image>

Common Prepubertal Conditions

Vulvovaginitis

Vulvovaginitis is the most common gynecologic complaint in prepubertal girls and is typically nonspecific. The etiology includes poor hygiene, chemical irritants such as soaps and bubble baths, respiratory pathogens including Group A Streptococcus and Haemophilus influenzae, and pinworms (Enterobius vermicularis). Management centers on hygiene education (front-to-back wiping), sitz baths, avoidance of irritants, and targeted antibiotics when a specific pathogen is identified. Red flags that warrant further evaluation include bloody or purulent discharge, which may indicate a foreign body, trauma, or sexually transmitted infection raising concern for abuse.

Labial Adhesions

Labial adhesions occur in 1 to 3% of prepubertal girls, with peak incidence at ages 1 to 2 years. The low estrogen environment leads to denudation and subsequent fusion of the labia minora. Treatment consists of observation if the patient is asymptomatic. When treatment is needed, topical estrogen cream (0.01% conjugated estrogen) is applied to the line of fusion for 4 to 6 weeks. Betamethasone 0.05% is an alternative. Surgical separation is reserved for cases with urinary obstruction or failure of medical therapy.

Lichen Sclerosus

In prepubertal girls, lichen sclerosus presents with white, atrophic plaques in a "figure-of-eight" distribution around the vulva and perianus. Histology shows epidermal thinning, loss of rete ridges, and homogenization of the dermis. Treatment is with high-potency topical corticosteroids (clobetasol propionate 0.05%) followed by a gradual taper.

Adolescent Gynecology

Abnormal Uterine Bleeding in Adolescents

Anovulatory bleeding accounts for the majority of cases in the first 2 to 3 years after menarche due to immaturity of the hypothalamic-pituitary-ovarian axis. The evaluation should include a complete blood count, TSH, pregnancy test, and coagulation studies. Notably, 20% of adolescents presenting with heavy menstrual bleeding at menarche have an underlying bleeding disorder, most commonly von Willebrand disease. Management includes combined oral contraceptives for acute stabilization, tranexamic acid for acute hemorrhage, and iron supplementation for anemia.

Primary Amenorrhea

Primary amenorrhea is defined as the absence of menarche by age 15 in the presence of secondary sexual characteristics or by age 13 without secondary sexual characteristics. The workup includes karyotype, FSH, LH, estradiol, prolactin, TSH, pelvic ultrasound, and MRI when indicated. Key diagnoses include Turner syndrome (45,X), Mullerian agenesis (Mayer-Rokitansky-Kuster-Hauser syndrome), complete androgen insensitivity syndrome, and constitutional delay of puberty.

<image>Diagnostic algorithm for primary amenorrhea showing branching pathways based on presence or absence of breast development and uterus, with associated etiologies at each endpoint</image>

Dysmenorrhea

Primary dysmenorrhea is caused by prostaglandin-mediated uterine contractions and is treated with NSAIDs and/or hormonal contraceptives. Secondary dysmenorrhea should be suspected in adolescents with pain unresponsive to first-line therapy. The prevalence of endometriosis in adolescents with chronic pelvic pain is 50 to 70%, making it an important diagnosis to consider in this population.

Congenital Anomalies

Mullerian Anomalies

An imperforate hymen presents at puberty with cyclic pain, hematocolpos, and a bulging blue membrane visible at the introitus. Treatment is surgical excision using a cruciate incision. A transverse vaginal septum produces a similar presentation and requires surgical excision with care taken to preserve vaginal length. Uterine anomalies are classified by the updated ASRM system, and the septate uterus is the most common anomaly associated with pregnancy loss.

Disorders of Sex Development

The evaluation of disorders of sex development includes karyotype, 17-hydroxyprogesterone, testosterone, anti-Mullerian hormone, and pelvic imaging. Congenital adrenal hyperplasia due to 21-hydroxylase deficiency is the most common cause of ambiguous genitalia in 46,XX newborns. A multidisciplinary approach involving pediatric endocrinology, urology, psychology, and genetics is essential.

<image>Anatomical cross-section illustration showing imperforate hymen with accumulated hematocolpos distending the vagina, with labeled structures including uterus, cervix, vaginal canal, and bulging hymenal membrane</image>

Examination Techniques

The frog-leg or knee-chest position is used for prepubertal examination, while the lithotomy position with stirrups is used for adolescents. Vaginoscopy using a pediatric cystoscope or hysteroscope with saline irrigation is employed for evaluation of vaginal bleeding or suspected foreign body in prepubertal girls. Examination under anesthesia may be necessary for trauma evaluation or when office examination is not feasible. For adolescent patients, establishing rapport, ensuring private interview time, and being aware of state-specific minor consent laws are essential aspects of care that respect adolescent confidentiality.

Clinical Pearls

Von Willebrand disease should always be considered in adolescents presenting with heavy menstrual bleeding at menarche. Screening coagulation studies should be part of the initial workup because 20% of these patients will have an underlying bleeding disorder.

Labial adhesions in prepubertal girls are almost always managed conservatively with topical estrogen or observation. Surgical intervention is rarely needed.

An imperforate hymen is a clinical diagnosis that should be identified and treated promptly at puberty to prevent complications of hematocolpos.

Any vaginal bleeding in a prepubertal child requires thorough evaluation including consideration of foreign body, trauma, infection, precocious puberty, and malignancy such as sarcoma botryoides.

Anovulatory cycles are physiologic in the first 2 to 3 years after menarche but should not be assumed without appropriate workup, particularly when bleeding is heavy enough to cause anemia.

References

1. Emans SJ, Laufer MR. Emans, Laufer, Goldstein's Pediatric and Adolescent Gynecology. 7th ed. Philadelphia: Wolters Kluwer; 2020.
2. ACOG Committee Opinion No. 580. Von Willebrand Disease in Women. Obstet Gynecol. 2013;122(6):1368-1373.
3. Dietrich JE, Millar DM, Quint EH. Obstructive reproductive tract anomalies. J Pediatr Adolesc Gynecol. 2014;27(6):396-402.
4. Styne DM, Grumbach MM. Puberty: ontogeny, neuroendocrinology, physiology, and disorders. In: Melmed S, et al., eds. Williams Textbook of Endocrinology. 14th ed. Elsevier; 2020.

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