Imperforate Hymen

Article Author:
Houda Abdelrahman
Article Editor:
Michael Feloney
Updated:
7/15/2020 1:55:04 AM
For CME on this topic:
Imperforate Hymen CME
PubMed Link:
Imperforate Hymen

Introduction

The hymen is a thin membrane of stratified squamous epithelium circumscribing the vaginal introitus. When the hymen does not spontaneously rupture during neonatal development, it is referred to as an imperforate hymen. An imperforate hymen can present with obstructive symptoms of the female genital and urinary tract during the perinatal, pediatric, or adolescent years and is a rare cause of primary amenorrhea. Infants with an imperforate hymen may develop a mucocele from endogenous maternal estrogen stimulation.[1][2] 

Many patients remain asymptomatic until menarche when they present with cyclic abdominal pain and amenorrhea. Hematocolpos or hematometra, the accumulation of menstrual blood in the vaginal or uterine cavities, can create a pelvic mass identified on physical exam as a blue, bulging perineal mass. This mass may cause mechanical obstruction of the urinary tract, leading to urinary retention, hydronephrosis, or acute renal injury. Corrective hymenectomy may be delayed until puberty unless the child suffers from urgent complications of the pelvic mass, prompting emergent surgery to preserve renal function, treat an infection, or minimize infertility.[3] Surgical treatment focuses on the prevention of recurrence of the imperforate hymen. Because pediatricians, gynecologists, and pediatric urologists encounter this diagnosis in their practice, a multi-disciplinary approach to evaluation and treatment is optimal for the patient.

Etiology

During urogenital development, the cloaca is divided by the urorectal septum to separate the ventral urogenital sinus from the dorsal anal canal. The Wolffian ducts (mesonephric ducts) and Mullerian ducts (paramesonephric ducts) are the two main ductal systems that give rise to specific structures in the male and female genital and urinary tracts. The Wolffian duct develops from the paired urogenital ridges and grows caudally to induce the formation of the mesonephric tubules. Additionally, the Wolffian duct induces the development of the Mullerian ducts from the coelomic epithelium of the paired urogenital ridges. The Mullerian ducts grow caudally using the Wolffian ducts as guides. The close association of the Mullerian ducts and Wolffian ducts during development explains the high incidence of urinary tract anomalies in women who also have Mullerian anomalies. The fusion of the Mullerian ducts forms the uterovaginal canal that gives rise to the uterus, cervix, and upper two-thirds of the vagina. The distal point of contact of the Mullerian ducts with the urogenital sinus is the site of the proliferation of the urogenital sinus epithelium, thereby forming the sinovaginal bulb. The sinovaginal bulb develops into the vaginal plate.

The embryological origin of the lower third of the vagina is the urogenital sinus. The precise embryological origin of the imperforate hymen is controversial. It is thought that the hymen normally perforates during the perinatal period at approximately 22 weeks. The most popular theory is that the hymen may fail to canalize with the rest of the vagina during development when the sinovaginal bulbs canalize at the site where the uterovaginal canal meets the urogenital sinus.[4][5] The imperforate hymen results from unsuccessful canalization of the vaginal plate and failed degeneration of the hymenal epithelial cells.[4] The hymen is likely derived from urogenital sinus posterior wall invaginations.[6]

Redundancy of the newborn hymenal tissue leading to an inverted appearance is a common finding at birth, and over half of the newborn females will have reduced tissue redundancy by one year of age.[7][8] As the influence of maternal estrogen subsides, the hymenal opening expands and may adopt a crescentic appearance.[8] Hymenal tags may spontaneously resolve and may also appear where there was not previously any tags.[8] In a study of 468 newborns, there was a significant difference in hymen characteristics by race but not gestational age or weight.[7] The most common normal hymenal types at birth are the annular and fimbriated forms.[7] Other hymenal variations that are considered abnormal include a microperforated, septate, and cribriform hymen.[9]

Microperforate hymen is thought to result when epithelial cells in the center of the developing hymen do not normally degenerate.[4] Because the hymen is not a Mullerian structure, there is not a high likelihood of urinary tract anomalies in association with imperforate hymen. Exceptions to this speculation are reported in the literature in case reports. However, these instances are likely due to random embryologic events.[10][11][12] While many imperforate hymen cases are considered to be isolated incidences, there are reports of familial occurrence of the imperforate hymen in autosomal dominant, autosomal recessive, and polygenic inheritance patterns.[6][13]

Epidemiology

The incidence of imperforate hymen is estimated to be 1 in 1000 female births.[14] The prevalence of urinary tract anomalies ranges from 4.2 per 10,000 births to 4.0 per 1000 births in studies of birth registries from different countries in Europe and Asia.[15][16][17][18][19][20] Unlike the higher incidence of renal anomalies in patients with Mullerian abnormalities, the incidence of such anomalies associated with an imperforate hymen is extremely rare. This overall rarity explains why the condition of multiple anomalies with imperforate hymen is primarily documented in case reports. However, the incidence of urinary retention and acute kidney injury in association with imperforate hymen on presentation is approximately 20% and 2%, respectively.[6] The incidence of other hymenal abnormalities is not known, with only approximately twenty case reports of microperforate hymen reported in the literature.[21]

Histopathology

The hymen is minimally innervated and predominantly consists of fibrous connective tissue with some elastic fibers and glycogen granules on the vaginal and vulvar surfaces. Both of its surfaces are surrounded by stratified squamous epithelium without glands.[22] This stratified squamous epithelium on histology is also supporting evidence for the non-Mullerian origin of the hymen, as the distal third of the vagina is derived from the urogenital sinus and is also lined by stratified squamous epithelium.

History and Physical

The presentation of an imperforate hymen is variable, depending on the patient’s age at presentation, the severity of the obstruction, and the clinical course. Additionally, the evaluation of the prepubescent child differs from the evaluation of the adolescent female. Abnormalities of the female genitalia may be difficult to discern on the newborn physical exam due to the excess hymenal tissue.

Hydronephrosis and pelvic masses can be detected as early as the 20-week prenatal ultrasound.[3] In interviews with patients’ parents, fever and fussiness are commonly reported. Parents may also report no changes in voiding behavior. Infants may have mucocolpos from the accumulation of vaginal and cervical gland secretions due to endogenous maternal estrogen stimulation. Early pediatric presentations may include urinary retention or hydronephrosis with a urinary tract infection or even acute lobar nephronia resulting from urinary tract obstruction.[23] 

Infants with imperforate hymen may not even demonstrate a perineal bulge on a physical exam. The imperforate hymen may also be subtle, even if ultrasound demonstrates bilateral hydronephrosis with a bladder distended to the umbilicus.[6] Therefore, the history and physical examination should be performed diligently with suspicion of this disorder. The common redundancy of the newborn hymenal tissue explains why hymenal abnormalities may be missed on the newborn exam by obscuring the abnormalities.

During the interview of the mature adolescent, clarifying the menstrual and coital history is important, since patients may report regular menses with a microperforate hymen. Cyclic monthly pain is often reported due to the menstrual blood that expands the vaginal canal and uterus with resultant hematometra. Expansion can cause numerous pelvic symptoms, including pelvic and back pain, constipation, back pain, radiated pain secondary to sacral plexus irritation, and urinary retention.[6] Up to three liters of retained blood has been reported in the literature.[24] Urethral coitus is a rare presentation of an imperforate or microperforate hymen due to accidental penetration of the urethra during intercourse, even if the patient denies issues with vaginal penetration and dyspareunia. Symptoms could also include coital incontinence and recurrent urinary tract infections.[25] 

The female genital exam starts with the identification of external structures to avoid overlooking anomalies prior to attempting a speculum exam. The physical examination of the adolescent may demonstrate a blue, bulging perineal mass that enlarges with the Credé maneuver. The Credé maneuver, application of manual pressure on the lower abdomen, exposes the imperforate hymen as a vaginal bulge.[3] If the hematosalpinx ruptures, the abdominal exam will demonstrate peritonitis.[26] The rectal exam may uncover a tender fluctuance posterior to the vagina and may reveal if there are absent structures proximal to the vagina.

Evaluation

Routine prenatal ultrasound at 20 weeks of gestation is a cost-effective method for evaluating the fetus’s urinary tract for renal abnormalities, duplex kidney, or hydronephrosis of various etiologies, including physiologic hydronephrosis or obstruction, urinary retention, or vesicoureteral reflux.[10] After delivery, pelvic ultrasound is critical in the evaluation of imperforate hymen in order to identify the hematocolpos and associated urinary tract obstruction, such as a distended bladder and/or hydronephrosis. Pertinent findings on ultrasound may be further evaluated with magnetic resonance imaging (MRI), the gold standard for assessing anatomical abnormalities.[20] Because a large pelvic mass can obscure pelvic anatomy, it is recommended to obtain a post-operative MRI if there is any concern for other urogenital anomalies.[12]

Treatment / Management

Spontaneous rupture of the asymptomatic imperforate hymen has previously been reported in 1 day and 1-month-old infants.[14] Ideally, this condition would be identified on the newborn physical examination so that asymptomatic patients could be managed expectantly prior to menarche.[2] However, patients with undiagnosed imperforate hymen often present acutely and require urgent surgical intervention to control symptoms and prevent abdominal complications, such as retrograde menstruation and endometriosis, and/or fertility complications. Definitive hymenectomy under anesthesia must be performed for drainage and relief of symptoms, rather than an in-office hymenotomy. Do not temporarily decompress the pelvic mass in the office through incision and drainage prior to definitive hymenectomy, as any incision performed outside the operating room risks the development of iatrogenic pelvic inflammatory disease and subsequent reclosure of the hymen.[27]

Other genital anomalies may be discovered at the presentation. Identification of an imperforate hymen prior to an acute presentation may assist with planned hymenectomy. Ideally, surgery should be deferred until puberty when the vaginal tissue is adequately estrogenized, which promotes wound healing after surgical incision of the hymenal tissue. Treatment options for an imperforate hymen include:

  1. Hymenectomy using cruciate or annular incisions
  2. Hymenectomy using electrocautery
  3. Placement of a 16Fr Foley catheter with 10ml balloon insufflation to preserve hymenal tissue
  4. Carbon dioxide laser treatment

Purulent vaginal fluid on needle aspiration may be found prior to drainage, which suggests that the hydrometrocolpos may become infected even before surgical intervention.

The traditional method of hymenectomy entails making a cruciate incision (cross-shaped) over the hymenal tissue with excision of the quadrants and approximation of the hymen edges to the vestibule with absorbable sutures. Other methods reported in the literature include hymen-sparing techniques. Annular hymenotomy using electrocautery to perform a circumferential annular (ring-shaped) hymenotomy reported no postoperative hymenal closure or scarred tissue beyond the hymenal contour in 14 patients aged 14.2 +/- 2.2 years at the time of surgery.[28] Another hymen-preserving technique used in a cohort of 65 patients aged 13.9 +/- 2.1 years involved making a 0.5 cm incision to accommodate an indwelling 16 F Foley catheter for two weeks with daily application of estrogen vaginal cream to promote epithelization. There were no reported infectious complications, but reclosure of the hymen was noted in two of the 65 women. This was attributed to the non-compliant application of the estrogen cream.[29] It is recommended that patients who are prepubescent apply topical estrogen due to the risk of spontaneous hymen reclosure after surgery.[3] Hymen reclosure may be associated with ascending infection and reproductive complications. A study of 13 patients ages 12 to 16 years who underwent carbon dioxide laser treatment to create a new orifice under local anesthesia resulted in no scarring or hymenal stenosis at the 2-week postoperative follow-up without estrogen cream and no report of dyspareunia at the 18-month time point.[30] 

The traditional treatment for microperforate hymen includes cruciate hymenectomy.[21] An alternative, novel treatment option in patients who do not have infectious symptoms or acute obstruction is the use of Hegar dilators to progressively dilate the vaginal introitus in the operating room under general anesthesia. The two patients who have undergone this technique had satisfactory outcomes without scarring and subsequent easy use of tampons, but no information on dyspareunia was reported.[4] In the circumstance of a septate hymen where the remnant hymenal tissue is not entirely obstructive, resection of the septum after tying both ends with absorbable suture in the office is appropriate using topical lidocaine cream.[31]

Differential Diagnosis

The differential diagnosis for a perineal mass in a newborn girl includes periurethral cyst, ectopic ureterocele prolapse, and vaginal botryoid sarcoma. Imperforate hymen is distinguished from a periurethral cyst by identification of the urethral meatus. Ectopic ureteroceles may prolapse from the urethra and have a congested appearance. Vaginal botryoid sarcoma usually has a multilobulated appearance.[32]

Other vaginal anomalies that result from developmental aberrancies of the urogenital sinus and Mullerian ducts must be distinguished from imperforate hymen and can also rarely occur in association with an imperforate hymen. Failure to diagnose these anomalies burdens the patient with further morbidity because the treatments are different. The main abnormalities include a transverse vaginal septum, vaginal atresia, and vaginal agenesis.

Failure of canalization at the point of contact between the urogenital sinus and the Mullerian duct results in a transverse vaginal septum. Transverse vaginal septa can be located at different levels within the vaginal (upper, middle lower). The septa may be associated with small perforations.[33] Vaginal agenesis is the congenital absence of the proximal vagina and may be associated with agenesis or hypoplasia of other Mullerian duct derivatives, including the fallopian tubes, uterus, and cervix. The cause of isolated vaginal agenesis is less well-defined, but when both the Mullerian tubercle and ducts are involved, the result is Mayer-Rokitansky-Kuster-Hauser syndrome. Women with MRKH syndrome may or may not have a hymen.[9]

Vaginal atresia results from an aberrancy in the urogenital sinus, possibly recanalization, such that there is a septum or stenosis. While patients with vaginal agenesis may not be able to conceive due to hypoplasia or absence of the fallopian tubes and uterus, pregnancy is possible for women with vaginal atresia after surgical correction. On physical exam, a rectal exam can help define the extent of the genital tract in children and whether there are vaginal septa or anomalies.[14] MRI is the gold standard for evaluating the pelvis and ruling out other Mullerian anomalies.[20] 

Imperforate hymen can present as part of a syndrome, such as McKusick-Kaufman syndrome, characterized by polydactyly, congenital heart disease, and hydrometrocolpos in females.[34] The hydrometromolpos can be caused by any obstructive anomaly of the female genital tract, including imperforate hymen or other anomalies, such as vaginal agenesis or vaginal atresia.

Prognosis

Successful drainage of an imperforate hymen satisfactorily resolves symptoms. Rarely, the imperforate hymen has been associated with neonatal death due to respiratory failure from the abdominal distension.[35] Even with post-operative infection following hymenectomy, hymen patency remains satisfactory.[3] The theoretical risk of dyspareunia is not well-elucidated in the literature. Adolescents treated with Foley catheter insertion to preserve the hymenal structure did not complain of severe dyspareunia at first coitus on follow-up.[29] At an average follow-up period of 8.5 years, women who underwent hymenectomy reported dysmenorrhea without complaints of sexual dysfunction. Successful live birth was reported among those that attempted pregnancy.[36] 

In another study, 86% of women conceived after hymenectomy without dyspareunia.[37] Dysmenorrhea is likely due to pelvic endometriosis from retrograde menstruation in women with imperforate hymen.[36] A long-term follow-up of 40 patients with either imperforate hymen or transverse vaginal septa found that patients with imperforate hymen had significantly better rates of successful term pregnancies.[37]

Vaginal adenocarcinoma is rare and was reported in a patient who had vaginal adenosis and a prior history of imperforate hymen.  Vaginal adenosis, the persistence of columnar epithelium in the vagina, was reported on colposcopic biopsies two years after hymenectomy in a 13-year-old patient who did not have estrogen exposure in utero. Another 20-year-old female who underwent hymenectomy and found to have granulated vaginal walls had colposcopy with biopsies positive for vaginal adenosis, which can be a precursor to vaginal adenocarcinoma. Another 14-year-old female presented for vaginal discharge and was found to have a red granulated vaginal wall with biopsies demonstrating adenosis. The authors hypothesized that vaginal adenosis associated with imperforate hymen may be related to undifferentiated paramesonephric tissue during development.[38]

Complications

The iatrogenic pelvic inflammatory disease has been documented after a patient underwent an office hymenotomy under sterile conditions. The surgical site had spontaneously sealed within one day when the patient was evaluated by an adolescent gynecologist who scheduled a hymenectomy in the operating room two days later. However, on postoperative day 7, the patient had a high-grade fever and had lower abdominal pain with MRI demonstrating right pyosalpinx requiring CT-guided drainage. This account illustrates that even small incisions into an imperforate hymen for symptomatic relief or confirmation of diagnosis should not be undertaken due to the risk of iatrogenic infection from the inoculation of bacteria into the hematocolpos.[27] Therefore, a patient who needs urgent hymenectomy due to infection or urinary tract obstruction should have the procedure performed definitively in an operating room under sterile conditions.

Hymen re-closure is a risk, thought to be increased in prepubertal patients due to a lack of estrogenization of genital tissue.[3] Hymen re-closure was documented in a 2-day-old infant who initially underwent bedside incision and drainage in the neonatal intensive care unit with same-day discharge, only to present at three weeks with perineal swelling and a bulging hymen. The infant underwent an annular hymenectomy in the operating room with sutures to approximate the hymen margins to the vestibule. Here, the authors comment on using suture or dilator at the time of hymenectomy to decrease closure risk.

Another case report of a 16-year-old girl who required four hymen surgeries due to re-closure had a Foley catheter placed for 3 to 4 days after the first three surgeries and, on her fourth presentation, underwent hymenectomy with continuous locked sutures and catheter placement for 14 days. No estrogen cream use was documented.[5] This case’s use of a Foley catheter is compared to Acar et al’s Foley catheter method, in which catheters were placed for two weeks with daily application of estrogen cream in a cohort of females aged 13.9 +/- 2.1 years. Inadequate hymenectomy with stenosis and closure is thought to contribute to the development of dyspareunia and infertility.[39]

Postoperative infection risk is not globally studied, but individual case reports and series report their own outcomes. The decision to administer pre-operative antibiotics is surgeon-specific and depends on patient factors, such as concern for possible pyosalpinx.[28] Not all surgeons administer pre-operative antibiotics. The hematocolpos is believed to provide a medium for bacteria to flourish within the anaerobic uterine environment.

Deterrence and Patient Education

Although some clinicians distinguish imperforate hymen from the other Mullerian anomalies due to its unique embryologic origin, urinary tract abnormalities may still be associated with imperforate hymen on presentation due to the effect of the pelvic mass that causes a mechanical obstruction of the urinary tract, leading to urinary retention, hydronephrosis, or acute kidney injury. Ultrasound is a low-cost modality for the detection of urinary tract obstruction and pelvic masses. During the newborn period, caretakers may be advised to notice perineal bulges during hygienic care and to review with a pediatrician or specialist, as appropriate.[14] If an imperforate hymen is identified, proper follow-up is necessary for timed hymenectomy prior to the onset of menses.

Enhancing Healthcare Team Outcomes

A team of pediatricians, gynecologists, and pediatric urologists are needed for the evaluation and treatment of imperforate hymen. In the case of an imperforate hymen, early diagnosis will prevent both short-term and long-term complications that may otherwise have a delayed, advanced presentation that may include acute kidney injury and even peritonitis.[26] 

Prompt diagnosis and treatment optimize both short-term symptom management and long-term reproductive potential while minimizing urologic complications. The positive impact on the patient from earlier diagnosis and treatment includes relief of suffering from pelvic pain, decreased morbidity related to infertility complications, and resolution of urinary tract obstruction. The successful surgical treatment promotes patency of the vaginal canal and prevents post-operative infection to reduce the risk of hospitalization or further procedures that bear morbidity to the pediatric patient.


References

[1] Ben Hamouda H,Ghanmi S,Soua H,Sfar MT, [Spontaneous rupture of the imperforate hymen in two newborns]. Archives de pediatrie : organe officiel de la Societe francaise de pediatrie. 2016 Mar;     [PubMed PMID: 26857644]
[2] Glavan N,Haller H,Brnčić-Fischer A,Glavan-Gačanin L,Miletić D,Jonjić N, Imperforate hymen presenting as vaginal cyst in a 16-month-old child - considerations for an early diagnosis. Scottish medical journal. 2016 Feb;     [PubMed PMID: 26659454]
[3] Grimstad F,Strickland J,Dowlut-McElroy T, Management and Prevention of Postoperative Complications in a Neonate with a Symptomatic Imperforate Hymen. Journal of pediatric and adolescent gynecology. 2019 Aug;     [PubMed PMID: 31029601]
[4] Segal TR,Fried WB,Krim EY,Parikh D,Rosenfeld DL, Treatment of microperforate hymen with serial dilation: a novel approach. Journal of pediatric and adolescent gynecology. 2015 Apr;     [PubMed PMID: 25444056]
[5] Ossman AME,El-Masry YI,El-Namoury MM,Sarsik SM, Spontaneous Reformation of Imperforate Hymen after Repeated Hymenectomy. Journal of pediatric and adolescent gynecology. 2016 Oct;     [PubMed PMID: 26876968]
[6] Lee KH,Hong JS,Jung HJ,Jeong HK,Moon SJ,Park WH,Jeong YM,Song SW,Suk Y,Son MJ,Lim JJ,Shin JI, Imperforate Hymen: A Comprehensive Systematic Review. Journal of clinical medicine. 2019 Jan 7;     [PubMed PMID: 30621064]
[7] Berenson A,Heger A,Andrews S, Appearance of the hymen in newborns. Pediatrics. 1991 Apr     [PubMed PMID: 2011421]
[8] Berenson AB, Appearance of the hymen at birth and one year of age: a longitudinal study. Pediatrics. 1993 Apr     [PubMed PMID: 8464674]
[9] Kimberley N,Hutson JM,Southwell BR,Grover SR, Vaginal agenesis, the hymen, and associated anomalies. Journal of pediatric and adolescent gynecology. 2012 Feb;     [PubMed PMID: 22051786]
[10] Eskandar O,Wheble A, Imperforate hymen in two sisters associated with renal angiomyolipoma and duplex kidney. Journal of obstetrics and gynaecology : the journal of the Institute of Obstetrics and Gynaecology. 2004 Nov;     [PubMed PMID: 16147654]
[11] Ogunyemi D, Prenatal sonographic diagnosis of bladder outlet obstruction caused by a ureterocele associated with hydrocolpos and imperforate hymen. American journal of perinatology. 2001;     [PubMed PMID: 11321242]
[12] Eksioglu AS,Maden HA,Cinar G,Tasci Yildiz Y, Imperforate hymen causing bilateral hydroureteronephrosis in an infant with bicornuate uterus. Case reports in urology. 2012;     [PubMed PMID: 22720183]
[13] Stelling JR,Gray MR,Davis AJ,Cowan JM,Reindollar RH, Dominant transmission of imperforate hymen. Fertility and sterility. 2000 Dec;     [PubMed PMID: 11119759]
[14] Kahn R,Duncan B,Bowes W, Spontaneous opening of congenital imperforate hymen. The Journal of pediatrics. 1975 Nov;     [PubMed PMID: 1185347]
[15] Postoev VA,Grjibovski AM,Kovalenko AA,Anda EE,Nieboer E,Odland JØ, Congenital anomalies of the kidney and the urinary tract: A murmansk county birth registry study. Birth defects research. Part A, Clinical and molecular teratology. 2016 Mar;     [PubMed PMID: 26833755]
[16] Bondagji NS, Antenatal diagnosis, prevalence and outcome of congenital anomalies of the kidney and urinary tract in Saudi Arabia. Urology annals. 2014 Jan;     [PubMed PMID: 24669120]
[17] Andrés-Jensen L,Jørgensen FS,Thorup J,Flachs J,Madsen JL,Maroun LL,Nørgaard P,Vinicoff PG,Olsen BH,Cortes D, The outcome of antenatal ultrasound diagnosed anomalies of the kidney and urinary tract in a large Danish birth cohort. Archives of disease in childhood. 2016 Sep;     [PubMed PMID: 27217581]
[18] Tain YL,Luh H,Lin CY,Hsu CN, Incidence and Risks of Congenital Anomalies of Kidney and Urinary Tract in Newborns: A Population-Based Case-Control Study in Taiwan. Medicine. 2016 Feb;     [PubMed PMID: 26844492]
[19] Laurichesse Delmas H,Kohler M,Doray B,Lémery D,Francannet C,Quistrebert J,Marie C,Perthus I, Congenital unilateral renal agenesis: Prevalence, prenatal diagnosis, associated anomalies. Data from two birth-defect registries. Birth defects research. 2017 Sep 1;     [PubMed PMID: 28722320]
[20] Friedman MA,Aguilar L,Heyward Q,Wheeler C,Caldamone A, Screening for Mullerian anomalies in patients with unilateral renal agenesis: Leveraging early detection to prevent complications. Journal of pediatric urology. 2018 Apr;     [PubMed PMID: 29459133]
[21] Tardieu SC,Appelbaum H, Microperforate Hymen and Pyocolpos: A Case Report and Review of the Literature. Journal of pediatric and adolescent gynecology. 2018 Apr     [PubMed PMID: 28838865]
[22] MAHRAN M,SALEH AM, THE MICROSCOPIC ANATOMY OF THE HYMEN. The Anatomical record. 1964 Jun;     [PubMed PMID: 14173802]
[23] Shen MC,Yang LY, Imperforate hymen complicated with pyocolpos and lobar nephronia. Journal of the Chinese Medical Association : JCMA. 2006 May;     [PubMed PMID: 16835985]
[24] CECUTTI A, HEMATOCOLPOS WITH IMPERFORATE HYMEN. Canadian Medical Association journal. 1964 Jun 20;     [PubMed PMID: 14159331]
[25] Underwood PG,Bauer J,Huguelet P,Alaniz VI, Delayed Diagnosis of Microperforate Hymen Leading to Urethral Dilation Secondary to Coital Activity. Obstetrics and gynecology. 2019 Mar;     [PubMed PMID: 30741808]
[26] Bakos O,Berglund L, Imperforate hymen and ruptured hematosalpinx: a case report with a review of the literature. The Journal of adolescent health : official publication of the Society for Adolescent Medicine. 1999 Mar;     [PubMed PMID: 10195807]
[27] Wong JWH,Siarezi S, The Dangers of Hymenotomy for Imperforate Hymen: A Case of Iatrogenic Pelvic Inflammatory Disease with Pyosalpinx. Journal of pediatric and adolescent gynecology. 2019 Aug;     [PubMed PMID: 30974214]
[28] Cetin C,Soysal C,Khatib G,Urunsak IF,Cetin T, Annular hymenotomy for imperforate hymen. The journal of obstetrics and gynaecology research. 2016 Aug;     [PubMed PMID: 27094100]
[29] Acar A,Balci O,Karatayli R,Capar M,Colakoglu MC, The treatment of 65 women with imperforate hymen by a central incision and application of Foley catheter. BJOG : an international journal of obstetrics and gynaecology. 2007 Nov;     [PubMed PMID: 17949378]
[30] Frega A,Verrone A,Schimberni M,Manzara F,Ralli E,Catalano A,Schimberni M,Torcia F,Cozza G,Bianchi P,Marziani R,Lukic A, Feasibility of office CO2 laser surgery in patients affected by benign pathologies and congenital malformations of female lower genital tract. European review for medical and pharmacological sciences. 2015;     [PubMed PMID: 26221878]
[31]     [PubMed PMID: 31135763]
[32] Sharifiaghdas F,Abdi H,Pakmanesh H,Eslami N, Imperforate hymen and urinary retention in a newborn girl. Journal of pediatric and adolescent gynecology. 2009 Feb;     [PubMed PMID: 19241622]
[33] Passos IMPE,Britto RL, Diagnosis and treatment of müllerian malformations. Taiwanese journal of obstetrics     [PubMed PMID: 32127135]
[34] Adam A,Hellig J,Mahomed N,Lambie L, Recurrent Urinary Tract Infections in a Female Child With Polydactyly and a Pelvic Mass: Consider the McKusick-Kaufman Syndrome. Urology. 2017 May;     [PubMed PMID: 28153592]
[35] Shaw LM,Jones WA,Brereton RJ, Imperforate hymen and vaginal atresia and their associated anomalies. Journal of the Royal Society of Medicine. 1983 Jul;     [PubMed PMID: 6876046]
[36] Liang CC,Chang SD,Soong YK, Long-term follow-up of women who underwent surgical correction for imperforate hymen. Archives of gynecology and obstetrics. 2003 Nov;     [PubMed PMID: 14605815]
[37] Rock JA,Zacur HA,Dlugi AM,Jones HW Jr,TeLinde RW, Pregnancy success following surgical correction of imperforate hymen and complete transverse vaginal septum. Obstetrics and gynecology. 1982 Apr;     [PubMed PMID: 7078896]
[38] Hansen K,Egholm M, Diffuse vaginal adenosis. Three cases combined with imperforate hymen and haematocolpos. Acta obstetricia et gynecologica Scandinavica. 1975;     [PubMed PMID: 1163224]
[39] Garden AS,Bramwell R, Treatment of imperforate hymen by application of Foley catheter. European journal of obstetrics, gynecology, and reproductive biology. 2003 Jan 10;     [PubMed PMID: 12475572]