Genital Tract Flashcards
What are the abnormalities associated with the Genital Tract in pregnancies?
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Ambiguous Genitalia
Ovarian Cyst
Urogenital Sinus
Ambiguous Genitalia
Prevalence: 1 in 5,000 births.
Ultrasound: Female fetus: clitoromegaly with normal labia.
Male fetus: micropenis, hypospadias, undescended testes, bifid scrotum.
On the basis of the cause, the condition is divided into:
True hermaphrodite: both ovarian and testicular tissue are found within the same gonad. The karyotype is female 46,XX, but there is a chromatinic material from the Y chromosome.
Female pseudohermaphrodite: virilized females with normal female karyotype and ovarian gonadal tissue. The causes include congenital adrenal hyperplasia (1 in 15,000), ingestion of androgens by the mother and maternal virilizing tumors.
Male pseudohermaphrodite: undervirilized males with normal male karyotype and testicular tissue. The causes include inadequate synthesis of testosterone or the presence of an androgen receptor defect.
Assoc abnorm: Chromosomal abnormalities, mainly trisomy 13, triploidy and 13q syndrome, are found in a few cases.
The condition is commonly associated with genetic syndromes:
Smith-Lemli-Opitz syndrome: autosomal recessive; ambiguous genitalia, microcephaly, cardiac, renal and gastrointestinal defects, syndactyly and polydactyly.
WAGR syndrome: sporadic; Wilms tumor, aniridia (absence of the iris), geniturinary malformations, neurodevelopmental delay.
Other defects, mainly facial clefts and cardiac defects are often found.
Follow up: In families with congenital adrenal hyperplasia, administering dexamethasome to the pregnant woman from 6 weeks’ gestation can minimize the effect of androgens on the genitalia and the developing brain. If the fetus is male, steroids should be discontinued.
Follow-up scans every 4 weeks to monitor growth and evolution of genitalia.
Prognosis: Treatment of a neonate with ambiguous genitalia should be performed by a multidisciplinary team, including geneticists, pediatric endocrinologists, and pediatric urologist. There is controversy concerning sex assignment and the need or not of reconstructive surgery.
Recurrence: Congenital adrenal hyperplasia: 25%.
Ovarian Cyst
Prevalence: 1 in 2,500 births.
Most common intra-abdominal cyst in female fetuses.
Ultrasound: Unilateral, unilocular cyst, sometimes containing a ‘daughter cyst’, in the abdomen of a female fetus >26 weeks’ gestation.
If the cyst undergoes torsion (40% of cases) or hemorrhage the appearance is complex or solid. Rupture can result in ascites.
Fetal ovarian cysts are sensitive to placental hormones and are more common in diabetic or rhesus isoimmunised mothers as a result of placental hyperplasia.
Large ovarian cysts (>6 cm in diamater) can cause polyhydramnios due to compression of the bowel.
Assoc abnorm: Most cases are sporadic and there is no association with chromosomal abnormalities.
A few cases are associated with genetic syndromes. The most common is McKusick - Kaufman syndrome (automosomal recessive; hydrometrocolpos, polydactyly, heart defects).
Other defects, mainly genitourinary (renal agenesis, polycystic kidneys) and gastrointestinal (esophageal atresia, duodenal atresia and imperforate anus), are often found.
Follow up: Ultrasound scans every 4 weeks to monitor the evolution of the cyst. If the cyst is >6 cm ultrasound guided aspiration should be considered.
Prognosis: The majority of cysts are benign and resolve spontaneously in the neonatal period. Surgery may be necessary if there is torsion.
Recurrence: Isolated: no increased risk of recurrence.
Urogenital Sinus
Prevalence: 1 in 250,000 births.
Ultrasound: Presacral cystic mass in the pelvis of a female fetus, due to a common channel for urinary and genital tracts. The mass represents hydrometrocolpos, distended vagina and a compressed, anteriorly located bladder with varying degrees of urinary obstruction. The contents may be clear (urine) or turbid (hemorrhage). Ascites may result from escape of urine through the Fallopian tubes into the abdomen.
Normal amount of the amniotic fluid.
Assoc abnorm: The incidence of chromosomal abnormalities or genetic syndromes is not increased.
Other defects, mainly of the genitourinary tract (bicornuate uterus, cervical atresia, vaginal atresia or duplication, hydronephrosis, renal agenesis, multicystic kidneys) gastrointestinal tract (imperforate anus, esophageal atresia) and cardiovascular system, are often found.
Follow up: Ultrasound scans every 4 weeks to monitor the evolution of the condition.
Prognosis: Neonatal evaluation of the exact anatomical picture and investigation for other anomalies of the genital and urinary tracts. Reconstructive surgery is necessary. Most patients are continent and fertile, but about 50% require intermittent catheterization.
Recurrence: Isolated: no increased risk of recurrence.
