Patient's question:
Why do natural miscarriages happen? I didn't engage in intense exercise or eat anything unusual! Yet, I had a miscarriage like this, and I didn't feel any physical pain either. I'm very confused and puzzled! What on earth is going on?Doctor's answer:
Hello:Natural miscarriage, in addition to factors such as genetics, infection, luteal insufficiency, and human chromosomal abnormalities, is also a primary cause of natural miscarriage due to uterine lesions.
1. Uterine Fibroids
The main cause of this condition is the compression and obstruction of the tumor tissue, which leads to deformation of the uterine cavity and gradual degenerative changes. The surface of the endometrium develops ulcers, and blood flow to the endometrium and myometrium decreases, making it unfavorable for the fertilized egg to implant and develop, resulting in miscarriage. For young women who desire fertility, uterine fibroid enucleation can be performed without hysterectomy to preserve fertility.
2. Cervical Incompetence
Pregnant women with cervical incompetence usually experience miscarriage in the second trimester. This is because, as the fetus grows and amniotic fluid increases, intrauterine pressure rises continuously, causing the cervix to protrude and leading to membrane rupture. Cervical incompetence is often associated with previous cervical laceration injuries, multiple induced abortions, or poor development of the uterine isthmus. Cervical cerclage during pregnancy (between weeks 12–15) or cervical repair during the non-pregnancy period can be effective in treating this condition.
3. Uterine Malformations
The human uterus is a muscular organ derived from the development of the paramesonephric ducts. Incomplete fusion of the bilateral ducts or incomplete resorption of the longitudinal septum after fusion can lead to various uterine malformations, such as congenital unicornuate uterus, bicornuate uterus, double uterus, and uterine septum. Uterine septum accounts for about 80% of uterine malformations and is the most common cause of natural miscarriage and preterm birth. The main reason the uterine septum causes miscarriage is ischemia in the septal area and poor endometrial development, resulting in insufficient blood supply to the fertilized egg and affecting normal fetal development.