Department of Obstetrics and Gynecology, Keciören Education and Research Hospital, Ankara, Turkey.
Department of Obstetrics and Gynecology, Tepecik Education and Research Hospital, Izmir, Turkey.
J Ultrasound. 2021 Dec;24(4):489-492. doi: 10.1007/s40477-020-00516-0. Epub 2020 Nov 25.
The aim of the study was to determine the accuracy of fetal sex definition by measuring the yolk sac size and the yolk sac-fetal pole distance in the first trimester via ultrasound (US) screening.
We enrolled 92 gestational women in this prospective study. In the first trimester of US examination, the gestational sac, the gestational sac-fetal pole distance, and the yolk sac size were measured. When the fetal pole was in the longitudinal position, the distance between the fetal pole and the yolk sac was measured in millimeters (mm). The crown-rump length (CRL) was measured in the same position. US examination at 22 weeks was performed to determine whether the fetal gender was male or female. The genders of the fetuses were recorded. The sexes were also confirmed and recorded after birth.
Fifty-five (59.8%) of the newborns were found to be male, while 37 (40.2%) of them were found to be female. We compared the yolk sac size and the yolk sac-fetal pole distance in both the female and male groups. We found that the genders showed a significant difference in terms of yolk sac-fetal pole distance, whereas the yolk sac size showed no significant difference between the genders. The optimal cutoff value of the yolk sac-fetal pole distance was 1.80 mm, with 70% sensitivity and 67% specificity for female gender prediction. The distance also showed an independent association with gender prediction in the first trimester.
Yolk sac-fetal pole distance may have the potential to predict gender in the first trimester of pregnancy.
本研究旨在通过超声（US）筛查测量妊娠早期卵黄囊大小和卵黄囊-胎儿极距，确定胎儿性别的准确性。
我们前瞻性地纳入了 92 名妊娠女性。在 US 检查的妊娠早期，测量孕囊、孕囊-胎儿极距和卵黄囊大小。当胎儿极位于纵向位置时，以毫米（mm）测量胎儿极与卵黄囊之间的距离。在同一位置测量头臀长（CRL）。在 22 周进行 US 检查，以确定胎儿性别是男性还是女性。记录胎儿的性别。在出生后确认并记录性别。
55 名（59.8%）新生儿为男性，37 名（40.2%）为女性。我们比较了女性和男性组的卵黄囊大小和卵黄囊-胎儿极距。我们发现，在卵黄囊-胎儿极距方面，性别存在显著差异，而在性别方面，卵黄囊大小没有显著差异。卵黄囊-胎儿极距的最佳截断值为 1.80mm，对女性性别预测的灵敏度为 70%，特异性为 67%。该距离在妊娠早期也与性别预测具有独立相关性。
卵黄囊-胎儿极距可能有潜力预测妊娠早期的性别。
