Features of Morphometric Parameters of the Placenta in Post-Term and Normal Pregnancy in Mongolian Women, Taking into Account the Placental-Fetal Ratio

Objective: To study the morphometric features of the placenta in Mongolian women with normal and post-term pregnancy in a comparative aspect. Materials and Method: The material for the study was the placenta taken after childbirth from 366 mothers with post-term pregnancies and 695 mothers with normal pregnancies who gave birth in 2017-2018. Morphometric measurement methods were used. For statistical processing of the results obtained, the statistical data analysis package SPSS 23 (IBM) was used. Results: The length of the placenta in women with normal pregnancy was 18.518 ± 1.468 cm, and with post-term pregnancy 19.485 ± 1.824 cm (t = 8.75), (p < 0.001). In women with normal pregnancy, the width of the placenta was 18.150 ± 1.565 cm, and in women with post-term pregnancy, 18.982 ± 1.897 cm (t = 7.20), (p < 0.001). The thickness of the placenta in women with normal pregnancy was 1.997 ± 0.388 cm, in women with post-term pregnancy 2.005 ± 0.432 cm (t = 0.30). The average weight of the placenta was 628.45 ± 86.298 g in women with normal pregnancy, and 721.21 ± 118.166 g in women with post-term pregnancy (t = 13.27), (p < 0.001). The average weight of a newborn was 3444.73 ± 267.766 g in the group with normal pregnancy, and 4094.39 ± 302.624 g in the group with post-term pregnancy, (p = 0.000). The placental-fetal ratio was 0.183 ± 0.00099 in the group with normal pregnancy, and 0.176 ± 0.00157 in the group with post-term pregnancy, (t = 3.77), (p < 0.001). Conclusion: The average values of the morphometric parameters of the placenta during post-term and normal pregnancy have a difference, being within the normal range. As the gestational age increases, the length, width, thickness, and weight of the placenta increase in different ways.