The perineal midsagittal view in male fetuses - pivotal for assessing genitourinary disorders

Imaging in fetal genital anomalies

Genital anomalies are a heterogeneous group of congenital pathologies that have become increasingly relevant since the Chicago Consensus of 2005. Their postnatal diagnosis has developed significantly in the last two decades, while prenatal diagnosis seems to be underdeveloped, with few protocols available, fragmented scientific literature, and low diagnostic rates. This review aims to examine the current status of this subspecialty from the perspective of prenatal imaging. Indications for the evaluation of fetal genitalia can be divided into medical and non-medical reasons. Medical reasons include sex-linked disorders, detection of other anomalies, relevant family history, or multiple pregnancy. Non-medical reasons include parental request for sex disclosure. Disclosure of fetal sex may be associated with ethical, legal, and medical issues. The main imaging technology used is 2D ultrasound, although there are other complementary techniques such as 3D, MRI, or Color Doppler. Regarding working methodology, several authors have drawn attention to the lack of standardized protocols and guidelines. Most guidelines tend to limit their recommendations to study indications and ethical issues. Technical proposals, measurements, or working methods have not yet been standardized. Fetal sex determination is usually divided into early and late gestation. Early gestation is based on the sagittal sign. Late gestation is based on direct visualization. There are several measurements to describe male and female genitalia, such as penile length, bilabial diameter, or scrotal diameter. Prenatal diagnosis of genital pathologies presents some particularities such as the wide spectrum of phenotypes, the high frequency of associated deformities, or the time of diagnosis. Some of the most frequent pathologies are ambiguous genitalia, fetal sex discordance, hypospadias, micropenis, clitoromegaly, ovarian cysts, hydro(metro)colpos, and cloacal anomalies. Higher-quality studies and direction from scientific societies through the implementation of clinical guidelines are needed.

The Development of Normal Fetal External Genitalia Throughout Gestation

In this review, we describe normal development of fetal genitalia throughout gestation as well as the identification of normal male and female genitalia on ultrasound. We use abnormal and ambiguous genitalia as illustrative tools to assist with the identification of normal genitalia and recognition of some of the most common abnormalities in external genitalia development.

[Genital abnormalities: Contextualization of a neglected area in prenatal diagnosis]

OBJECTIVE

To reflect on how the area of genital abnormalities has fallen behind in prenatal diagnosis.

METHODS

Based on the thesis that prenatal diagnosis of genital abnormalities has scarcely developed, a comparison with other areas of prenatal diagnosis and with its postnatal counterpart is presented; different explanations for this situation are examined; and a reflection is presented on ways to expand this field of knowledge.

CONCLUSIONS

Compared to other disciplines, prenatal diagnosis of genital abnormalities finds itself lagging behind in terms of diagnostic tools, management protocols and scientific literature. Potential causes include a perception of low prevalence and limited importance, or exploration challenges. Integration of current knowledge, together with the acquisition of the appropriate tools and translation to clinical medicine, would be a way to make this discipline stronger.