The "female echo": prenatal determination of the female fetus by ultrasound

The Predictive Accuracy of Anogenital Distance and Genital Tubercle Angle for First-Trimester Fetal Sex Determination

BACKGROUND

Early identification of fetal gender is crucial for managing gender-linked genetic disorders. This study aimed to evaluate the predictive performance of anogenital distance (AGD) and genital tubercle angle (GTA) for fetal sex determination during the first trimester.

METHODS

A multicenter retrospective cohort study was conducted on 312 fetal cases between 11 and 13 + 6 weeks of gestation from two tertiary hospitals. AGD and GTA measurements were taken from midsagittal plane images using ultrasound, with intra- and inter-reader reproducibility assessed. Binomial logistic regression and ROC curve analysis were employed to determine the diagnostic performance and optimal cutoff points.

RESULTS

AGD had a mean of 7.16 mm in male fetuses and 4.42 mm in female fetuses, with a sensitivity of 88.8%, specificity of 94.4%, and an area under the ROC curve (AUC) of 0.931 (95% CI: 0.899-0.962) using 5.74 mm as a cutoff point. For GTA, the mean was 35.90 degrees in males and 21.57 degrees in females, with a sensitivity of 92%, specificity of 84.7%, and an AUC of 0.932 (95% CI: 0.904-0.961) using 28.32 degrees as a cutoff point. The reproducibility results were excellent for AGD (intra-operator ICC = 0.938, inter-operator ICC = 0.871) and moderate for GTA (intra-operator ICC = 0.895, inter-operator ICC = 0.695).

CONCLUSIONS

The findings suggest that AGD and GTA are reliable markers for early fetal sex determination, with AGD showing higher reproducibility. The findings highlight the feasibility and accuracy of these non-invasive sonographic markers and their potential usefulness in guiding timely interventions and enhancing the management of gender-linked genetic conditions.

Mothers' and fathers' changing perceptions of their male and female infants over the course of pregnancy

Twelve pregnant women and their spouses who had undergone ultrasonography and knew their child's gender were compared with 12 pregnant women and their spouses who had undergone ultrasonography but did not know their child's gender. Parents were interviewed (a) prior to receiving the ultrasound, (b) immediately after the ultrasound, and (c) following their infant's birth. Using the adjectives rating scales, and replicating the procedures developed by Rubin, Provenzano, and Luria (1974), parents' perceptions of their infants were measured. ANOVA results indicated that parents viewed their infants to be softer, finer, littler, cuddlier, easier, calmer, more inactive, more beautiful, more awkward, quieter, weaker, and somewhat more delicate following birth than during the preceding measurement period(s). Mothers viewed their infants to be softer, more nervous, more fussy, more excitable, and more noisy than did fathers. Supporting Rubin et al.'s (1974) findings, several differences emerged between parents' perceptions of boys and girls, particularly by the time the infants were born. Following birth, parents perceived girls to be finer, smaller, less coordinated, quieter, weaker, and more delicate than boys. No differences were found as a result of parents being informed of their infants' gender prior to birth.

Sonographic determination of fetal sex from twelve weeks of gestation

Fetal sex was sonographically determined in 1879 pregnant women between 12 and 40 weeks of gestation by obtaining transverse, frontal, and sagittal sections of the fetal lower pelvic region. The success rates of producing echoimages that were sufficient to determine fetal sex were 97.1% for both sexes (7783 correct diagnoses out of 8010 sonograms), 97.1% for males (3986/4103), and 97.1% for females (3797/3907). Postnatal confirmation of the sex of 1886 newborn infants delivered of 1879 pregnant women revealed that the rate of correct diagnosis before delivery was 99.9% (1885/1886)-100% for males (957/957) and 99.8% for females (928/929). The method of ultrasonic examination of the fetal sex reported here appears to be feasible in obstetric practice with consistent reproducibility and a high incidence of correct determinations at 12 weeks of gestation and thereafter.

Prenatal diagnosis--a compilation of diagnosed conditions

This article provides physicians with an up-to-date listing of 182 fetal conditions diagnosed prenatally. This information is presented in two key tables: the first an alphabetical listing of the conditions and the second a grouping of them according to disease categories. The latter table also presents the technique(s) used to establish the diagnosis, as well as pertinent references. Chromosomal abnormalities, diagnosed from amniotic fluid cell karyotypes, have not been individually tabulated in either table. Current techniques utilized for prenatal diagnosis are presented (see Comment).

Determination of fetal sex with ultrasound

In a consecutive series of 137 pregnancies scanned at 24 weeks' gestation or later, the sex of 66% of infants was determined with a 2% error rate. By means of ultrasound examinations, parents may now be offered the opportunity of knowing the sex of their baby before delivery.