ULTRASOUND PARAMETERS OF THE UTERUS AND ENDOMETRIUM IN FERTILE PAROUS WOMEN OF ACTIVE REPRODUCTIVE AGE

 

Minashkina E.V.^1,2, Ozhogina E.V.², Ozerskaya I.A.³

 

1 - Sechenov University.

2 - Nova Clinic Reproduction and Genetics Center.

3 - Patrice Lumumba Peoples' Friendship University of Russia. Moscow, Russia.

To assess morphometric and hemodynamic ultrasound parameters of the uterus and endometrium in fertile parous women of active reproductive age (25-37 years) during the mid-secretory phase of the menstrual cycle.

Materials and methods. This retrospective cohort descriptive study included 127 healthy women aged 25-37 years (parity: 1-4), examined on days 20-22 of the menstrual cycle. All participants underwent 2D/3D transvaginal ultrasound with 3D power Doppler imaging. Endometrial volume was automatically calculated using the VOCAL software. The following parameters were analyzed: uterine volume, endometrial thickness and volume, endometrial area in the coronal plane (via 3D reconstruction), vascularization indices (VI, FI, VFI), pulsatility index (PI) of the uterine arteries, and time-averaged mean velocity (Vmean) of blood flow in the uterine arteries. Statistical analysis included descriptive statistics, Spearman’s correlation coefficients, and p-values.

Results. Normative ultrasound parameters were established for fertile parous women in the mid-secretory phase of the menstrual cycle. The mean uterine volume was 57.2 ± 17.0 cm³, endometrial thickness was 9.3 ± 1.4 mm, and the median endometrial volume was 7.3 cm³. The median vascularization indices of the endometrium (VI, FI, VFI) were 10.7%, 13.1, and 2.9, respectively. The mean blood flow velocity (Vmean) in the uterine arteries was 7.99 ± 1.97 cm/s, and the pulsatility index (PI) was 2.02 ± 0.29. Correlation analysis revealed a strong association between endometrial volume and uterine cavity area (ρ = 0.76), as well as synchronized vascularization of the myometrium and endometrium (ρ = 0.65). An increase in parity was associated with higher volumetric and vascular parameters of the endometrium, while PI remained stable, suggesting morphofunctional vascular adaptation after completed pregnancies.

Discussion. The obtained results demonstrate that the morphometric and hemodynamic characteristics of the uterus and endometrium in fertile parous women during the mid-secretory phase are indicative of high physiological maturity and pronounced perfusion. Compared to population data, uterine and endometrial volumes and vascular indices were slightly elevated, likely reflecting morphofunctional adaptation following completed reproductive cycles. The identified correlations between morphometric and vascular parameters support the anatomical and functional integration of these structures. A moderate increase in endometrial vascularization with higher parity highlights a potentially enhanced receptivity of the endometrium in women with multiple pregnancies.

Conclusion. The derived reference ranges address the gap in data on ultrasound parameters in healthy parous women and offer a reliable clinical basis for evaluating endometrial receptivity and uterine status during in vitro fertilization preparation. These findings can serve as reference indicators in practical gynecology and reproductive medicine.

 

Keywords: endometrium, uterus, 3D ultrasound, reproductive health, vascularization indices.

 

Corresponding author: Minashkina E.V., e-mail: Этот e-mail адрес защищен от спам-ботов, для его просмотра у Вас должен быть включен Javascript

 

For citation Minashkina E.V., Ozhogina E.V., Ozerskaya I.A. Ultrasound parameters of the uterus and endometrium in fertile parous women of active reproductive age. REJR 2026; 16(1):65-79. DOI: 10.21569/2222-7415-2026-16-1-65-79.

Received: 11.07.25 Accepted:            03.09.25