The number one concern for families undergoing IVF is the IVF success rate. For doctors, the first step in the success of IVF is the ability to retrieve quality eggs. What are the factors that affect the success rate of IVF. This article by Shenzhen Fusheng Assisted Fertility Center takes you through these influencing factors, and there are secrets to success, according to which we can actively make positive adjustments in order to improve the success rate.
First: the physical factors of the operator are key
Physical factors can be subdivided into five aspects: age, chromosomes, intrauterine environment and infertility symptoms and weight.
1. Age
Age is a reflection of the normal and vigorous female reproductive system. According to research experts, the pregnancy rate of couples of childbearing age is only 20%, and after women enter the age of 35, all body functions will decline, among which the reproductive system is particularly prominent. And age is an important factor in the success of IVF technology, domestic and foreign literature reported that the age of 25-34 years old the highest success rate, more than 35 years old after the success rate will have a significant decline in performance, more than 40 years old success rate of about 20%, and the live birth rate decreased significantly, and the impact on eugenics is also greater. The success rate of IVF treatment for older women is much higher than that of younger women because the success rate is extremely low and the chromosomes of the embryos are prone to abnormalities.
2. Chromosomes
In some couples with primary infertility or a history of bad pregnancy, some of them have normal variant of chromosomes. These couples with chromosomal problems can conceive through IVF technology, but the failure rate and miscarriage rate are higher.
3. Intrauterine environment, endometrium is important
The endometrium is the most important site for embryo implantation causing damage to the endometrium, myometriosis, endometritis, endometrial polyps or other lesions of the endometrium may cause embryos to fail to implant and affect the success rate. New research has found that the endometrium secretes a special sugar molecule, and when this sugar molecule is lacking, the conception rate is greatly reduced. It is believed that in the near future, medical doctors will overcome this problem and improve the success rate of pregnancy.
Uterine factors: Just as fertile soil is needed for planting, the right endometrium is needed for implantation to occur. When uterine abnormalities are present, such as polyps, submucosal fibroids, uterine adhesions, endometritis, and various other pathologies, the chances of implantation may be reduced. It has been clearly demonstrated that hysteroscopy can identify and address the etiology and significantly improve the implantation rate in some patients with recurrent failure. Endometrial scratching during the luteal phase may also be performed to improve endometrial receptivity in patients with recurrent failures who have normal uterine cavity morphology.
Hysteroscopy Uterine adhesions
Fluid in the fallopian tubes: fluid in the fallopian tubes contains various “poisons” which, if left untreated, can “wash away”, “drown” and “poison” the embryos if they reflux into the uterine cavity. If left untreated, the reflux into the uterine cavity can “wash away” and “drown” the embryos, thus greatly reducing the chance of embryo implantation. For patients with repeated failures, the first thing to do is to check whether the tubes are combined with hydrosalpinx. If there is hydrosalpinx, it is recommended to deal with the hydrosalpinx first by ligation or removal of the tubes to remove the effect of fluid on implantation. If the pelvic adhesions are too severe for surgery, tubal mucosal plugging can also be considered.
4. Patient’s infertility symptoms, previous pregnancy history
Older primary infertility, patients with severe endometriosis and polycystic ovary syndrome with uterine malformation, those who do not get sperm from the testes of patients with severe oligospermia or azoospermia, or those who have a large number of malformed sperm, and those who have abnormal eggs or abnormal development, also have a high failure rate in IVF treatment.
There is another type of woman who is able to conceive but always miscarries before the fetus is full term; they are another type of infertility who have a higher success rate with IVF than those who never conceive. According to Resolve of the National Infertility Association, “infertility is defined as 2 or more consecutive miscarriages.”
Resolve recommends that women who have undergone multiple miscarriages should visit a hospital to check hormone levels, the thickness and health of the uterine lining for underlying uterine structural abnormalities, potential chromosomal problems such as chromosomal aneuploidy, ectopic and inversions. All of these conditions will produce fewer embryos than those with intact and healthy chromosomes, and they can all lead to miscarriage, as well as serious infant health problems.
5. Weight
While not all women who are underweight or overweight have difficulty conceiving, some of them do have some impact. The American Society for Reproductive Medicine points out that a BMI (body mass index, is now commonly used internationally to measure the degree of body fat and thin and whether a standard of health) of 18.5 or lower (underweight) may lead to irregular menstrual cycles and stop ovulation, while the BMI shows that obese women may also produce irregular menstrual cycles, as well as ovulation promotion. Therefore, women with a BMI of 29 or higher should see a doctor to check the hormonal status associated with ovulation.
In addition, many weight-related problems may be associated with certain underlying conditions, such as polycystic ovary syndrome (PCOS), diabetes or thyroid disease – all of which can affect a woman’s fertility. It is also important to note that obese women have lower IVF success rates and higher miscarriage rates.
Second: Excellent embryo rates
Excellent embryos are important for success when there are problems with sperm and eggs, and neither fertilization nor fertilization without oogenesis can complete an embryo transfer. According to the six levels of embryo grading: fresh embryos of grade I-IV are available for transfer, and grade I. II are excellent embryos. At present, excellent embryos are only morphologically classified and the potential of embryos is not known. Now, embryologic chilblains are working on a more advanced method of embryo assessment that will hopefully predict the probability of conception of embryo sculptures.
However, excellent embryos also require a good uterine environment, good endocrine conditions, and the physician’s superior embryo transfer technique. Couples of normal fertile age who have intercourse at the time of ovulation for 1 month have only about 20% chance of pregnancy. That is why we hope to have a good state of mind during the treatment, which is also an important factor for success. Therefore, this factor is closely related to the physical factors of the operator. Based on the current medical technology, it can be said that the physical condition of the couple undergoing IUI determines the success rate of excellent embryos.
Third: the number of embryos transferred
Toner points out that although triplets and quadruplets are not usually obtained through IVF these days, twins are still very common. Although parents think twins mean wearing the same clothes and using a double stroller, twin pregnancies and births actually carry considerable risk in some areas, such as quadruple the risk of cerebral palsy, speech delays, learning disabilities and more.
How many embryos will be transferred in any given IVF cycle?Toner says he hopes Patient
Predictor can show patients, “One at a time is fine, and some times one is even better.” And, “It’s common that putting back one embryo at a time has a better chance of getting pregnant than putting back two embryos at a time.”
Fourth: immune factors
1. immune abnormalities: studies suggest that abnormally elevated activity of systemic or local natural killer cells may have toxic effects on embryos and impede implantation. This can be treated by intravenous infusion of immunoglobulin or fat milk. In addition, active immune deficiency can be induced by injecting husband lymphocytes to induce active immune function in oneself. However, there is controversy about the effectiveness of various treatments for immune abnormalities.
2. Coagulation abnormalities: Coagulation abnormalities such as “antiphospholipid syndrome” and “easy embolism” lead to thrombosis in small blood vessels of the placenta, resulting in insufficient blood supply to the endometrium and decreased chance of embryo implantation or increased risk of miscarriage. The prevention and treatment can be carried out by aspirin, corticosteroid, low molecular heparin, etc.
Fifth: psychological state factors
Many data show that the psychological and mental state of the patient is an important factor affecting the success or failure of IVF treatment. A psychological assessment of couples undergoing IVF treatment was done using a psychological test scale. The evaluated groups were also compared. The results of the study found that the group that had received psychotherapy to relieve stress had almost one times worse conception rates than the group that had not undergone psychotherapy, when age, education, cause of infertility, treatment plan, amount of medication, and embryo quality were all essentially the same.
In women with high psychological stress, their endocrine secretion is affected and their blood vessels are in a state of permanent constriction, which affects the local blood flow to the uterus and ovaries. Moreover, the nervous system tension causes abnormalities in the release of some neuromediators, resulting in disorders in the contraction of the muscles of the uterus and fallopian tubes, causing the embryo not to be able to get laid.