Ultrasonic Evaluation of Uterine Endometrial Morphology in the Normal Menstrual Cycle

Abstract

Recent advancement of ultrasonographic technology enables vivid visualization of the female reproductive tract and the indirect detection of ovulation. This technique is now applied in induction of ovulation, timing artificial insemination, oocyte retrieval for in vitro fertilization and embryo transfer(lVF & ET). Twenty normal ovulatory cycles were investigated in order to elucidate the cyclic ultrasonographic changes of uterine endometrial morphology (dates: March, 1984 to February, 1985). Demonstration of ultrasonic endometrial changes revealed that the early proliferative phase was characterized by a long thin endometrium which became much thicker, giving evidence of growth in endometrial glands and stroma. The stromal cells of the superficial layer may be separated by transudate which was ultrasonically demonstrated by a hyporeflective area. Following ovulation, we observed the 'ring' sign as an evidence of ovulation. The thickness of the central midline uterine echogenic area was 6.6 ±1.2 mm in the early proliferative phase. It became 11.8± 1.4 mm on the day of ovulation(detected by ultrasound examination) and 12.3 ± 1.2 mm in the late secretory phases. We concluded that ultrasonic evaluation of the endometrial morphology accompanying ovarian follicle monitoring is helpful in determining the dating as well as the confirmation of the progestational effect on the endometrial tissue and in detecting other organic pelvic disease related to infertility and menstrual disrdoers.