Seven types of women are most likely to suffer from infertility

Among infertility cases, male factors account for about 40%, female factors account for about 40%, and unexplained infertility accounts for about 20%. In female infertility, fallopian tube factors account for about 40%, ovulation factors account for about 40%, unknown causes account for about 10%, and the remaining 10% are uncommon factors. The main causes of female infertility are as follows:

1. Infection:

Most fallopian tube diseases are secondary to infection, especially pelvic inflammatory disease (PID). Other causes include appendiceal perforation, post-abortion infection, etc. Adhesions can lead to occlusion of the fallopian tubes. Studies have shown that the incidence of acute PID is approximately 10 to 13 per 1,000 females aged 15 to 19 years, and increases to 20 per 1,000 at the age of 20 to 24 years. The high prevalence of sexually transmitted diseases (STIS), such as chlamydia infection, is also an important reason for the increased incidence of PID. In addition, appendiceal perforation is an important factor causing tubal infertility, and infectious abortion is another major risk factor for tubal infertility.

2. Endometriosis:

It is currently considered controversial whether potentially small or mild endometriosis (stage 1 or 2) causes infertility. It may be due to pelvic adhesions and inflammatory factors that lead to subfertility, while stage 3 or 4 endometriosis may cause infertility due to severe pelvic adhesions, which may cause fallopian tube distortion and ovulation dysfunction.

3. Adhesions after surgery:

Adhesions can affect pregnancy rates. If pregnancy has not occurred one year after tubal recanalization surgery or if a serious disease is found during surgery, in vitro fertilization-embryo transfer (IVF-ET) may be the only option.

4. Reproductive tract malformations:

The incidence of uterine malformation in fertile women is 1:594, while in infertile women it is 1:28. This result shows that the incidence of congenital uterine malformations in infertile women is 21 times higher than that in normal women. Among the uterine malformations, 7% are saddle-shaped uterus, 34% are uterine septate, 39% are bicornuate uterus, 11% are didelphic uterus and 5% are unicornuate uterus. Saddle uterus and didelphic uterus have no significant effect on infertility. The pregnancy loss rate in patients with incomplete uterine septate is significantly increased, and the infertility rate in patients with unicornuate uterus is significantly increased.

5. Exposure to diethylstilbestrol (DES):

It is closely associated with uterine malformations, such as short tortuous tubes and smaller openings with wrinkled fimbriae. Nodular isthmic salpingitis represents bulging of the isthmic tubal mucosa into the muscularis or even subserosa. Although there is conflicting evidence about congenital and infected diverticula, it is clearly closely associated with infertility and ectopic pregnancy. Other malformations such as the opening of the accessory fallopian tube and the syndrome of long fallopian tube cilia are also closely related to infertility.

6.Asherman’s syndrome:

This abnormality is most commonly caused by recent operations that affect the endometrium, such as dilation and curettage of the uterus during pregnancy, myomectomy, etc. Endometrial tuberculosis can also cause this disease. Through hysteroscopy, the grading of intrauterine adhesions is comprehensively judged based on the range that the uterine cavity can reach. In severe cases, amenorrhea symptoms may occur. Hysteroscopic resection is the basic treatment for Asherman's syndrome.

7. Uterine fibroids:

The incidence of uterine fibroids in women over 35 years old is 20%~25%. Submucosal fibroids are an important cause of infertility, and submucosal fibroid resection is also the main indication for infertility treatment. There is controversy over the impact of intramural fibroids on infertility. Most studies believe that fibroids less than 4 cm in diameter have little effect on fertility, and their removal before childbirth increases the risk of uterine rupture during pregnancy. However, for patients with repeated infertility treatment failures and repeated miscarriages, myomectomy before pregnancy can be considered.