In order for the fertilized egg to be implanted in the uterine cavity and grow and develop into a new life, the uterus is fully prepared physiologically and morphologically. If the ratio of estrogen and progesterone is imbalanced, it will definitely affect the synchronous growth of the endometrium and accordingly affect the implantation of fertilized eggs. Sometimes, the fertilized egg and the endometrium are out of sync, which can also affect the fertilized egg\’s implantation.
Just like the fallopian tubes and cervix, the uterus may be abnormally shaped or incapable of receiving and cultivating an embryo.
(1) Abnormal shape of the uterus: The uterus is in the 10th to 16th week of fetal development. Forming. The two fallopian tube systems, the Mueller\’s ducts, enlarge and join into a separate structure, which forms the uterus. If this process is incomplete, a baby girl may be born with a separate uterus, two completely separate uteruses, or no uterus at all. These situations occur relatively rarely. The most common structure is a thin piece of fibrous tissue dividing the uterus (septate uterus), or it is separated by a muscular wall (bicornuate uterus). These conditions usually have 1 cervix and 1 fallopian tube on each side. Another type of congenital uterine abnormality is caused by the mother taking diethylstilbestrol within 12 to 16 weeks of pregnancy to prevent miscarriage. In some cases, taking this drug can cause a girl\’s cervix to become longer but her uterine cavity to be smaller. If it is determined that diethylstilbestrol causes a T-shaped uterus, pregnancy will be very difficult. If the irregularity is not severe, pregnancy may be possible. But because the uterine cavity is small, the possibility of premature birth is very high.
(2) Congenital uterine anomalies and pregnancy: Severe and rare congenital uterine anomalies cannot be corrected , it is neither possible to get pregnant nor to cultivate the embryo until delivery. When the abnormality in the shape of the uterus is minor, pregnancy is possible. Such patients must be treated by specialized and skilled physicians. If the uterus is separated by a thin fibrous wall (septum), which has neither blood supply nor nerves, it is much easier to remove this fibrous wall than to remove the muscle barrier, which requires More complex surgeries. Hysterosalpingography often detects a divided uterus, which can be detected by magnetic resonance imaging or abdominalLaparoscopy further confirms this, and sometimes ultrasound can show whether the wall is a septum or muscle tissue. If the septum is muscle, it will be visible outside the uterus during laparoscopy. Sometimes it is possible to get pregnant without removing the barrier, but sometimes it is necessary to remove the barrier. Although there is insufficient data to prove this, the risk of miscarriage is very high, especially if the uterus is separated by a septum. Women with uterine abnormalities should discuss all risks and possible difficulties, such as miscarriage, premature birth, or difficult labor, with their doctor before trying to become pregnant.
(3) Uterine dysplasia: Uterine dysplasia is also called immature uterus, which generally refers to uterine dysplasia. The situation when the uterus is still smaller than normal after pregnancy. Simply having a small uterus is not necessarily the direct cause of infertility. If the ovaries are underdeveloped at the same time, there is little hope of fertility.
(4) Endometritis: Infection of the endometrium is called endometrium inflammation. According to the length of the disease, it can be divided into two types: acute and chronic. According to the pathogenic bacteria of the infection, it can be divided into tuberculosis, venereal disease and general bacterial infection, but sometimes there is no obvious inducement. Among infertile women, the incidence of endometritis found through endometrial biopsy can reach 9.4%. Common pathogenic bacteria are mostly Staphylococcus aureus, Escherichia coli, Streptococcus aureus and anaerobic bacteria. However, gonococcal, mycoplasma, and chlamydial infections have increased significantly in recent years, and have become the main pathogenic bacteria in some areas. Clinical manifestations include increased leucorrhea, irregular uterine bleeding, backache and abdominal distension, which often occur during menstruation. The acute phase manifests as fever, purulent vaginal discharge with a foul odor, uterine tenderness, and an increase in white blood cells. If timely measures are not taken and thorough treatment is not taken, it will gradually turn chronic. Endometrial congestion, edema, a large amount of inflammatory exudation, and a large number of plasma cells and lymphocytes in the interstitium. These changes can affect the movement of sperm and the implantation and development of pregnant eggs. Of course, when there is inflammation, the endometrium cannot provide enough nutrition for the implanted egg, and the inflammatory exudates can also kill sperm, causing infertility. If treatment with live antibiotics fails, diagnosing and curettage can help patients remove infected endometrial tissue.
(5) Uterine fibroids:Uterine fibroids are the most common tumors in women. According to the relationship between fibroids and the myometrium of the uterus, they are divided into intramural fibroids, subserosal and submucosal fibroids. The extent to which fibroids affect pregnancy is related to the location, size, and number of fibroids. Submucosal fibroids growing in the uterine cavity are like foreign bodies in the uterine cavity that mechanically hinder the implantation of a fertilized egg. For example, if the fibroid shows ischemic necrosis, the patient will have repeated irregular vaginal bleeding, causing endometritis, which will also form inflammation and cause discomfort.pregnancy factors. Fibroids growing in the cervix compress the cervical canal, hinder the movement of sperm or change the position of the cervical canal, causing the neck opening to deviate from the semen pool in the posterior fornix, which is not conducive to the upward movement of sperm. Fibroids that grow in the broad ligament and uterine horns can compress and distort the fallopian tube when they grow to a certain size, hindering the movement of fertilized eggs and the egg-picking function of the fimbriae, causing infertility. Large intramural fibroids can deform the uterine cavity, which is not conducive to the upward movement of sperm and affects implantation of the fertilized egg and fetal development. Uterine fibroids often occur simultaneously with endometrial proliferative changes, endometriosis, and adnexitis. These complications are also important causes of infertility. Pay attention to distinguishing uterine fibroids and polyps. The latter are often small and can be treated through diagnosis and curettage. Management of uterine fibroids is complex. Uterine myomectomy is an operation to remove fibroids and leave the uterus intact. Some doctors believe that this surgery is only temporary and can bring hope to women who are looking forward to pregnancy, but about 20% of women will undergo another hysterectomy. Women with a history of myomectomy must end their delivery by caesarean section when their pregnancy is full term, because uterine scars may cause unsafe factors for vaginal delivery. The surgical technique for fibroid enucleation is more complicated than that of hysterectomy, and the intraoperative bleeding is high. Therefore, for patients with large fibroids and obvious separation of the uterine cavity, fibroid enucleation is not appropriate, and it is best to consult an expert in infertility treatment.
(6) Uterine adhesions syndrome: Uterine adhesions are also one of the causes of infertility . Adhesions in the uterine cavity, uterine isthmus, cervical canal, and secondary infection caused by trauma, and clinically present amenorrhea, oligomenorrhea, and infertility are called uterine cavity adhesions syndrome, also known as Asherman syndrome. The front and back walls of the normal uterine cavity are close to each other, but because the endometrium is intact, adhesions are unlikely to occur. Even if the functional layer of the endometrium is peeled off during menstruation, the basal layer is still intact and adhesions will not occur. Trauma (curettage, aspiration) and secondary infection are the main causes of this syndrome. Of course, hysteroplasty is also a cause. 56% of adhesion sites occurred in the uterine cavity, 24% affected the uterine cavity and cervical canal, and 20% were in the uterine isthmus. Intrauterine adhesions deform the uterine cavity or block the opening of the fallopian tube, causing infertility. The deformation of the uterine cavity and insufficient blood supply to the endometrium can lead to miscarriage or premature delivery. Occasionally, very thin membranous adhesions are located just at the opening of the fallopian tube. This hidden cause of infertility can only be discovered under hysteroscopy. Hysteroscopy involves inserting a catheter into the uterine cavity through the cervix and performing an examination under direct vision. In 3% to 5% of hysteroscopies, this kind of membranous scar tissue that hinders the movement of sperm and fertilized eggs can be discovered and treated at the same time.
(7) Endometrial insufficiency: Endometrial insufficiency can be divided into intrauterine membrane atrophy, abnormal endometrial hyperplasia, and luteal phase endometriumThere are 3 main types of insufficiency. Endometrial atrophy occurs because the ovaries do not produce estrogen or the endometrium lacks response to hormones, and the endometrial glands and stroma do not develop and proliferate. This lining is seen in anterior hypopituitarism and ovarian dysplasia. Excessive endometrial hyperplasia or glandular cystic or adenomatous hyperplasia are mostly caused by ovulatory dysfunction. Luteal phase endometrial insufficiency. Such patients can ovulate and fertilize normally, but the endometrium at the site of implantation of the fertilized egg is not fully developed, which affects their conception mechanism.
(8) Endometriosis: Endometriosis is a disease in the uterus Gynecological diseases caused by membrane growth in any part outside the uterine cavity. For example, it can occur in the ovary, uterosacral ligament, serosa layer of the posterior wall of the lower uterine segment, uterine rectal lacunae, and pelvic peritoneum of the sigmoid colon. It can also occur in the myometrium. Therefore, endometriosis is clinically classified as external. Type endometriosis and intrinsic endometriosis. Patients often seek medical attention complaining of infertility, dysmenorrhea, and pelvic pain. According to reports at home and abroad, the infertility rate of endometriosis patients reaches about 40%. Endometriosis is one of the main causes of infertility. Clinically, for women who complain of infertility, if their fallopian tubes are unobstructed, their basal body temperature is biphasic, their endometrium responds well, and their post-coital tests are normal, they should be considered to have a uterus. Possibility of endometriosis. Infertility caused by partial endometriosis has unobstructed fallopian tubes and no abnormal changes in pelvic anatomy. The reasons for infertility are as follows: ① The amount and composition of ascites and infertility. ②Endometriosis can be accompanied by anovulation. ③Ovarian luteal phase defects. ④ Luteinized unruptured follicles syndrome (LUF). ⑤ Increased levels of interleukin-1 and interleukin-2 in ascites are associated with infertility. ⑥ Increased prostaglandin secretion in ascites and infertility. ⑦Hyperprolactinemia. ⑧Autoimmunity and infertility.
This article is provided by Baidu Reading and is excerpted from \”The Clear \”Conception\” Plan\” Author: Sun Jianqiu and Xie Yingbiao