What are the causes of infertility? Hear what the experts have to say

Famous doctors consult online to protect your and my health. Huashang Daily-Ersanli Information "Famous Doctor Consultation" column invited: Wang Linlin, resident expert of the Department of Gynecology and Reproductive Medicine of peking university Third Hospital, and Liu Na, director and deputy chief physician of the Department of Gynecology and Reproductive Medicine of Yan'an Traditional Chinese Medicine Hospital, to chat with you about gynecology-related issues.

1. What are the causes of infertility?

First of all, we need to understand what infertility is. Fertility refers to a woman's ability to conceive, and the precise definition of infertility refers to the inability to conceive after 1 year of regular and unprotected sex. When we tried to analyze the causes of low fertility, we found that independent male factor infertility, female factor infertility, and both husband and wife factor infertility each accounted for 30%, and another 10% of infertility couples were unexplained infertility that could not be identified.

To determine the cause of infertility, we first need to understand the general process of female conception: after each menstrual menstrual period, the follicles in the ovaries will gradually develop, mature and ovulate, and when the eggs are picked up by the fallopian tubes, the eggs will gradually move through the fallopian tubes in the direction of the uterine cavity; at the same time, the sperm enters the cervix through the vagina, meets the egg through the uterine cavity and combines to become a fertilized egg, and when the fertilized egg implants and grows in the uterine cavity like a constantly developing seed, We can say that this woman was successfully conceived.

From this, we can see that any of the factors that affect the above conception process are the causes of female infertility. And this includes the most commonly heard: abnormal ovarian function, ovulation disorders, fallopian tube abnormalities, uterine abnormalities, etc. If you want to know what kind of factors infertility you are, you need to go to the hospital to improve the relevant tests.

2. How to prepare before the test tube can improve the pregnancy rate?

Although some patients have been diagnosed with infertility, not all infertility patients need "IVF" treatment, so first we need to fully assess our physical condition, through the hormone level (sex hormone six items) to understand their own endocrine level, ultrasound to understand the uterus and ovaries (such as endometrium, fibroids and ovarian size and other aspects). The focus is also on some indicators of ovarian reserve function, such as laboratory tests for AMH, B ultrasound assessment of the number of sinus follicles, etc. If it is only an ovulation dysfunction, ovulation induction treatment can be performed; if the man's semen level is slightly reduced, artificial insemination can be used to conceive.

Secondly, it is very important to adjust the mentality, some patients are overly nervous, anxious, these bad emotions will affect the final success rate, and "IVF" is not a panacea to ensure that everyone succeeds once, it may take several attempts, so don't be depressed because of a failure. In addition, do not blindly supplement nutrition, diet should be reasonable, diet with scientific collocation. Prepare for test tubes, such as supplementing with protein, vitamins, folic acid, etc., but in moderation. Finally, adhering to a certain amount of exercise can improve physical fitness while avoiding overnutrition during pregnancy. Overweight not only affects the quality of the eggs, but is more likely to bring about the adverse effects of other endocrine disorders.

3. What is a generation, second generation, three generation test tubes?

In fact, the first, second and third generations of test tubes are not a distinction of rank.

Let's start with the first and second generations of IVF, in fact, there are two different ways of fertilization at this time. "Generation IVF" we also call conventional in vitro fertilization (IVF). This type of fertilization is the most commonly used method, when the egg and sperm are removed from each husband and wife, they are put together, and a sperm actively drills into the egg to form a fertilized egg. Ivf insemination requires normal sperm from the man and is mainly aimed at infertility caused by female factors. For IVF, which we often call "free love", it allows sperm and eggs to be freely combined in a "test tube" outside the body, and the fertilization rate is about 65% to 75%. The advent of IVF technology effectively solves most of the infertility caused by female factors.

The "second-generation test tube" is also known as single sperm intracytoplasmic injection (ICSI), which uses micromanipulation techniques to inject a single sperm into an intracytoplasmic sperm under a microscope for fertilization. ICSI fertilization is mainly used for patients with severe hypothermia and obstructive azoospermia, which we call "arranged marriage". It is a technique of artificially selecting sperm and passively injecting sperm into the egg, with a fertilization rate of about 75% to 85%. The emergence of ICSI effectively solves most of the male factors of infertility.

So is the second generation more successful than the first generation? In fact, the above success rate is only for the success rate of sperm-egg combination fertilization, not the probability of the final successful pregnancy. And because the ICSI method is a traumatic invasion of the egg, the egg needs to be punctured, penetrating the pellucida and membrane of the egg, injecting sperm and its very small amount of culture solution. The controversy over the safety of this technology has never stopped. Although more than one million healthy babies have been born with ICSI technology to date, its long-term safety has yet to be evaluated.

Then the "three-generation test tube", that is, PGD, also known as preimplantation genetic diagnosis/screening (PGD/PGS), that is, before embryo transfer, take the genetic material of the embryo for analysis, diagnose whether there is abnormality, screen healthy embryo transfer, and prevent the transmission of genetic diseases. In general, sampling does not affect embryonic development. For ungeneral genetic diseases; and detection of chromosomal diseases. Three generations of IVF are required when either spouse has a genetic disorder, a chromosomal disorder, or has given birth to a child with such a disorder.

4. Are twins the best choice for IVF?

People in IVF treatment generally pursue success rates, and it is often heard that many couples hope to have twins at once, preferably dragon and phoenix fetuses, in one step. In fact, in the eyes of obstetricians and pediatricians, twin pregnancies are never the best choice, obstetrics has always regarded twins as high-risk pregnancies, and mothers and babies are at risk; in the incubators of neonatology, many are premature babies with IVF twins. If IVF transfers two embryos, the twin rate will exceed 32%. When the doctors at the fertility center recommend that you transfer an embryo, this will not reduce the success rate of each embryo, but it can greatly reduce the twin rate.

According to the statistical results of large samples, the incidence of twins in natural pregnancy is about 10‰ to 12 ‰, but with the wide application of ovulation-stimulating drugs and IVF, the incidence of overall twin pregnancies in the population has increased by 50% to 70% in the past 30 years.

As early as 2004, British and American experts identified twins as a complication of IVF treatment. Twin pregnancies seriously endanger the health of mothers and children, mothers are prone to gestational hypertension, gestational diabetes, gestational anemia, late miscarriage, premature rupture of membranes, premature birth, caesarean section and postpartum hemorrhage rate increased, maternal mortality rate increased by 2 times; the incidence of neonatal preterm birth, low birth weight, neonatal death and disability, neonatal birth defects increased.

5. What is the relationship between having a child and the thyroid gland?

When tested for infertility, some patients wonder why their doctors are giving them a thyroid function test.

In fact, thyroid disease is a common endocrine disease in women of childbearing age, and its incidence is only diabetes, and normal thyroid function can not only maintain the normal energy metabolism and growth and development of the human body, but also closely related to women's reproductive function. Common hypothyroidism and thyroid dysfunction can lead to changes in estrogen metabolism, resulting in various types of menstrual irregularities, ovulation disorders, thereby affecting the chance of conception, and also adversely affecting pregnancy outcomes.

6. Do you need to lose weight before pregnancy?

Answer: As the saying goes, "one white covers three ugliness, one fat destroys everything". Now the improvement of living standards, more and more obesity, unconsciously on the stomach on a swimming circle. In fact, there are many indicators to judge obesity, the most commonly used is the body mass index (BMI) = kg / ㎡. The normal BMI of the Chinese group was 18.5 to 23.9, with more than 24 being overweight and more than 28 being obese. Recently, there has been an increasing emphasis on waist circumference and body fat percentage as important tools for assessing obesity. If the waist circumference of men is greater than 90cm and that of women is greater than 80cm, it can be classified as obese. Even if the weight is normal, the waist circumference is not large, the body fat of men is higher than 25%, and the female is higher than 30%, which is considered to be an obese family. This kind of "skinny fat man" is easy to be unaware of the improvement of living habits and diet structure, resulting in the accumulation of visceral fat and more likely to have health problems. Obesity can affect any stage of a woman's life, but there is growing evidence that obesity can severely affect a woman's fertility. For women of childbearing age between the ages of 18 and 35, obesity may lead to: menstrual disorders, menstrual disorders; ovulation disorders and infertility; inducing a series of endocrine abnormalities and metabolic disorders such as hyperandrogenemia and insulin resistance; altering the secretion levels of important cytokines in the body (such as leptin, follicle-stimulating hormone FSH, luteinizing hormone LH, etc.); poor endometrial function and susceptibility to spontaneous miscarriage.

Our pregnant mothers-to-be cannot turn a blind eye to obesity, especially infertile women, and we cannot ignore the harm caused by obesity to fertility because of their urgent desire to have children. Weight control is of great significance, not only for this long-awaited birth, but also to establish a permanent and healthy lifestyle, so that the complications of pregnancy are greatly reduced, the mother and child are safer, the future of the child is more secure, and the long-term cardiometabolic diseases can be prevented, and the best is that this treatment cost is the lowest and the most cost-effective.

Scholars around the world have suggested to women who are preparing to give birth, weight loss before pregnancy is the most economical, effective and safest golden time in life, missing this opportunity, the subsequent weight loss will be adversely affected by fertility, pregnancy, complications and other adverse effects, becoming difficult. Want to be a mom? Please do the fat sister paper first "control the mouth, step on the legs", and then consider receiving infertility-related treatment, and finally get a successful pregnancy. There is a large amount of evidence that weight loss of 5% to 10% can already improve the clinical symptoms and ovulation function of obese women, restore the menstrual cycle, and many people can even conceive naturally. Therefore, if you don't lose weight now, the month will be sad in vain.

7. Is biochemical pregnancy a miscarriage?

If the biochemical pregnancy does not last, is it a miscarriage? Does a biochemical pregnancy count as a pregnancy? We know that the first step of pregnancy, sperm and egg must meet and combine, forming an embryo, while the embryo develops, the endometrium is also actively preparing for the arrival of the embryo; when the embryo and the endometrium develop in unison, the blastocyst and the endometrium in the accepting state will be further intimate contact, and finally the blastocyst drills into the endometrium layer, and the embryonic trophoblast establishes a close connection with the endometrium, which is the implantation of the embryo; if an abnormality occurs in a certain link before the establishment of this connection, This will cause the embryo to fail to implant, and of course it will be impossible to get pregnant. Biochemical pregnancy simply refers to the natural termination of the embryo before the gestational sac is formed. Biochemical pregnancy can also refer to the implantation of the embryo, but then for some reason, the embryo does not continue to grow healthy and then withers, the β-HCG in the blood also declines; the reason why it is called "biochemical pregnancy", the accurate test of β-HCG shows that the incidence of pregnancy loss after embryo implantation is about 31%, while the incidence of miscarriage after clinical pregnancy is about 15%. Pregnancy loss occurs early, we have not yet had time to find the formation of the gestational sac in the uterus through B ultrasound, this pregnancy is terminated, in the past we also called it "early embryonic wilting", "early pregnancy miscarriage".

In medical terms, the reason why we are afraid to define biochemical pregnancy as miscarriage is that there is another possibility. The embryo implants in a place outside the endometrial space, such as fallopian tubes, cervix, ovaries, etc., and cannot continue to develop, and it dies naturally. Because we did not find a gestational sac in the uterine cavity, such an early pregnancy, curettage often can not prove the pregnancy in the uterus, how to prove where the embryo has been laid? This conjecture of potential ectopic pregnancy, you can not deny and overturn.

"Biochemical Pregnancy" indicates that your little angel has come before, but only made a short stay and quietly left. A single biochemical pregnancy or miscarriage has its own contingency and can continue to try to conceive; if multiple biochemical pregnancies occur, especially for those who have become pregnant after IVF treatment, they need to seek the help of a doctor to find the cause.

What tests do I need to do after a biochemical pregnancy? How long does it take to get pregnant again?

Biochemical pregnancy is an early and early miscarriage, embryo implantation is soon eliminated caused, many women have this experience, "menstruation delay" for a few days to come, in fact, biochemical pregnancy, most of the situation is unconsciously occurring. The current consensus is that biochemical pregnancy is not counted in the gestational grade, but it needs to be followed up until the HCG value is completely normal to distinguish it from ectopic pregnancy and trophoblastic disease. After the HCG is normal, it is possible to try to conceive again after restoring 1 normal menstruation. It should be noted that if it is a recurrent biochemical pregnancy, it is necessary to consult a doctor to check the cause.

8. How big is the follicle that is excellent? To conceive?

Every time you go to test your follicles, the follicle size on the report sheet is different?! This month's follicles are inexplicably not up to standard, resulting in this month's "man-making plan" being ruined again? What's going on here? What kind of follicles are the best and most fertile? The normal growth of follicles is complicated by the function of the ovaries themselves and the hypothalamic-pituitary-ovarian axis, as well as the central nervous system and endocrine system. In general, the lifespan of sperm is 2-3 days, while the life of eggs after ovulation is shorter, and it will gradually age in 15 hours; therefore, two days before ovulation to 10 hours after ovulation is a critical time for conception. When the follicle diameter > 10 mm, it is called the dominant follicle; when the follicle diameter reaches >18 mm, it is called a mature follicle. Multiple follicles develop simultaneously at the beginning of each menstrual cycle, but generally only 1 or 2 follicles develop to maturity, called the main follicle (dominant follicle), and the rest of the follicles are closed successively. Ultrasound imaging of follicles can be performed as early as days 5-7 of the menstrual cycle and shows a minimum diameter of 4-5 mm.

On days 3 to 5 of the menstrual cycle, ultrasound can find small follicles in the ovaries, and then gradually grow, with the largest on the average day 14, and ovulation can occur. From day 5 of menstruation to before ovulation, the main follicle grows by an average of 1.5 mm per day; before day 10, it grows by an average of 1.2 mm per day, and the average growth of 1.9 mm in the 4 days before ovulation is until the follicle matures. Follicles are an important component of the endocrine system in a woman's body, and within two days after ovulation, the egg will encounter normal sperm in the fallopian tubes, and then form a fertilized egg and become pregnant. If the follicles appear abnormal, there is no way to get pregnant normally, so female friends usually pay attention to conditioning their health.

9. What kind of follicles are susceptible to conception?

First, good follicles should be large enough. The ideal follicle can reach a mature follicle when it reaches 18 to 25 mm in diameter when it matures, and follicles of this size are more likely to conceive after ovulation, and smaller than or larger than this range are not very good. The corpus luteum formed by small follicles has poor function, and some follicles do not rupture and do not ovulate after maturity, and grow until 30 to 40mm, they lose their ability to ovulate, and they cannot get pregnant. Secondly, the shape of the follicle is also important. Fullness and roundness are signs of good follicle quality, if the follicle is flat - the difference between the two diameter limits seen by B ultrasound ≥ 3 mm, such as 15 mm× 20 mm, it means that the quality of the follicle is relatively poor.

Finally, the number of follicles on one side of the ovaries is also critical. If there are multiple follicles developing in one side of the ovary at the same time, but there is no obvious dominant follicle, it may be suffering from an endocrine disease - polycystic ovary syndrome, and it is difficult to ovulate normally and conceive if not treated.

10. After "IVF", I am pregnant again, how is it echoed?

"IVF" technology has been carried out for nearly 40 years, which has brought good news to the vast majority of infertility patients, and is widely used in the fertility of fallopian tube factor infertility, endometriosis, ovulation disorders, male oligospermia and unexplained infertility. However, there are also some confusing situations, some patients who have not been pregnant for many years have naturally become pregnant after a period of successful pregnancy and childbirth through IVF; there are also some infertile couples who have natural pregnancy after a period of ivory infant fertility failure. Many people can't understand, what is going on with this phenomenon? What are the reasons behind this?

First, the probability of natural pregnancy after assisted fertility technology

For this probability, there is no accurate epidemiological data at home and abroad to support it. In some follow-up work after IVF, it is true that individual cases of natural pregnancy after IVF will be found. The case of natural pregnancy after the failure of IVF has been reported by a small number of scholars in China. It has been reported that patients younger than 37 years of age have a natural pregnancy rate of about 6% to 10% in the subsequent 2 years after the failure of assisted fertility technology. Another 13 patients with tubal factor infertility were reported within 6 months of failure of IVF treatment, of which 11 had a natural pregnancy and 2 had a natural pregnancy within 2 years. A 48-year-old infertile patient who gave up treatment after multiple assisted reproductive technology treatments without pregnancy, naturally became pregnant and gave birth at the age of 50. In 2016, a British medical student sent a questionnaire to couples after IVF fertility within 6 years, and 403 cases responded to valid letters, 118 cases became pregnant naturally within 6 years after fertility, of which 84 couples were successful in the previous IVF fertility and 34 couples were not successful in IVF. The highest incidence of natural pregnancy is unexplained infertility (39%) and ovulation disorders. The vast majority of natural pregnancies occur within 4 years of IVF surgery.

Second, the causes of natural pregnancy after assisted fertility technology

1. Psychological factors are an important influencing factor of natural pregnancy after assisted fertility technology. Some patients who have successfully conceived and given birth after IVF fertilization have relaxed their mood after achieving their family's and personal wishes for many years, which is more conducive to natural conception. For some patients who have failed IVF, the complete abandonment of the birth plan may also be given the opportunity to get pregnant. The causes of this analysis may be to alleviate the interference of mental tension and anxiety caused by long-term infertility treatment on the hypothalamic-pituitary-ovarian axis, which may make the reproductive endocrine system in the patient tend to be coordinated. Although the exact mechanism is not yet fully understood, there is no doubt that changes in psychological factors are undoubtedly an important factor contributing to this reversal.

2. Different infertility factors affect the natural pregnancy after IVF fertility

Unexplained infertility, which is the highest incidence of natural pregnancy after IVF. Unexplained infertility is based on: routine semen in the man; double pelvic biastomy; ovulation monitoring; hysterosalpingogram, and no clear cause is found after a four-step examination. Some specious causes, such as the man's mild oligospermia, sparse ovulation, mild endometriosis, and "unsmooth" fallopian tubes, are often artificial and subjective, inaccurate, and cannot be pronounced as infertility. However, these "hats" bring great distress to the patient's psychology, but affect the normal conception. As soon as there is a chance, a natural pregnancy occurs by chance. Therefore, in general, we will not be able to wait for 2 to 3 years for unexplained infertility, if age and ovarian function allow, or do several artificial inseminations, but many couples are impatient and are not willing to wait.

Ovulation disorder factors

People with ovulation disorders are also a major group of people who are part of IVF treatment. Most of these patients have normal tubal function and often choose IVF because they are not pregnant after multiple ovulation induction or have poor ovulation induction effects. In the subsequent IVF fertility process, the application of ovulation-stimulating drugs and the effect of follicle puncture in egg retrieval surgery have improved the local microenvironment of the patient's ovaries to a certain extent, enhanced the ovarian response to gonadotropins, and naturally ovulated to obtain pregnancy. It has been reported that the natural pregnancy of patients with such ovulation disorders occurs within 6 months after the birth of assisted fertility technology, which has the ovulation sequelae effect of assisted fertility technology.

Tubal factors

30% to 40% of patients undergoing IVF treatment are tubal infertility, which is an important group for IVF treatment. At present, most of the diagnostic methods for tubal infertility are completed by indirect tests such as tubal iodine oil contrast (HSG) and ultrasound. Methods such as HSG are not the gold standard for the evaluation of tubal patency, and often give false positive results, giving patients with original tubal patency the hat of "tubal obstruction". Although doctors have been fully informed of the existence of this false positive, some patients often choose IVF technology because of their eagerness to get pregnant as soon as possible.

In summary, there is also the possibility of natural conception after IVF treatment, which is activated after a long-term "strike" of the reproductive system, and the magic of natural pregnancy again appears in a "flash of inspiration", which is related to a variety of factors. However, if the incidence is too high, it also indicates that the indications of IVF technology are not strictly mastered, depriving couples of the opportunity to conceive on their own early.

Therefore, for patients who have successfully given birth to children after IVF treatment, there is still a need for planned contraception; for patients who have failed IVF, do not completely lose confidence, maybe a good pregnancy is waiting for you!

11. Is drinking soy milk helpful for fertility?

In the infertile female population doing "IVF", the news that "soy milk can improve the success rate of IVF", many women have joined the army of drinking soy milk, and there are many questions to consult doctors, "Can drinking soy milk improve estrogen?" "How much is appropriate to drink per day?" "Is there a problem with drinking too much soy milk?" Can it produce cancer? First of all, soy milk and other soy products belong to the category of "phytoestrogens", in human and animal diets, such as infant formula, animal feed, vegetarian diet, Chinese herbal medicine, rich in a large number of legume-derived phytoestrogens, as well as a wide variety of health products, these foods and nutritional products are widely advertised as health foods, especially soybean isoflavones, accounting for a high proportion of the diet of the Asian population.

In recent years, phytoestrogens have been defined by several international public health organizations as "endocrine disruptor compounds" (EDCs), which are exogenous factors that mimic or antagonize natural hormones that cause changes in the body's endocrine function. Like many man-made industrial chemicals, phytoestrogens are abundant in the environment in which we live, will it also cause some kind of human disease, or biological change? There are many scientists in the world who study phytoestrogens and divide them into four categories: isoflavones, flavonoids, coumarins, lignans, and soybeans are one of the most important sources.

A large number of basic studies have found that the affinity of these phytoestrogens with estrogen receptors in the body is much lower than that of natural estradiol, but because of the regulatory binding to estrogen receptors, it has a high bioavailability (50%/4.5%), and the concentration of phytoestrogens in circulation is in ng, which is one order of magnitude higher than the pg level of natural estradiol. With the change of industrial life, humans and animals consume more and more phytoestrogens, and long-term exposure is inevitable.

In fact, phytoestrogens belong to selective estrogen receptor modulators (SERMs), which induce allosterism after binding to estrogen receptors, and have anti-estrogen biological effects in humans, unlike rodents. That is to say, the ladies drank soy milk, thinking that it increased the estrogen in the body, in fact, to a certain extent, or in a part of the tissues and organs, inhibited the effect of estrogen.

Animal experiments have found that phytoestrogens act on fetal hypothalamic neurons during pregnancy, can produce cycle and reproductive problems, and in humans may even be related to endometriosis, polycystic ovary syndrome, premature ovarian failure and other diseases. But some clinical investigations have also found that the anti-estrogenic effects of phytoestrogens may be beneficial for breast cancer. It can inhibit the action of some estrogen synthases, which are highly expressed in the mammary glands.

Regarding the effect of phytoestrogen on the reproductive axis, although some associative phenomena have been observed and a large number of experimental studies of the mechanism of action have been carried out, there is still a lack of high-quality evidence-based evidence, and it is still difficult to accurately study the epidemiology of this type. For the health and safety of humans, the evaluation and exploration of phytoestrogens should also be carried out urgently.

Therefore, ladies who drink soy milk, do not blindly follow uncertain health information, in fact, drinking soy milk does not help to increase estrogen, can increase some plant protein. If you drink soy milk and soy products, it is also recommended to cook slowly for a long time, long-term high temperature can degrade some of the components of phytoestrogens, westerners are also learning to Chinese way to make soy products to reduce the adverse effects of phytoestrogens.

Huashang Daily reporter Jia Lingwei Editor Mana