The birth of beautiful twins is something that many mothers are eager to have, and it would be great if they could have a pair of dragon and phoenix fetuses to make a good word, but it is important to know that the pregnancy of twins is still a small probability event and should not be forced, not to mention the indiscriminate use of drugs such as multi-baby pills. What are the differences between a twin pregnancy and a singleton pregnancy? Is it safe to have a twin pregnancy? I would like to introduce you to the problems related to twin pregnancy. What are the chances of conceiving twins under normal circumstances? According to medical statistics, there is only a 1/89 chance of conceiving twins naturally, which is about 1% chance of conceiving twins. Is it possible to artificially influence the probability of having twins? We may feel as if the number of twins is increasing in our daily lives, but this is actually influenced by some factors. Through foreign statistics we can see that in the 80’s twins accounted for less than 1% of the rate, while in 04, 05, twins reached 3% of the frequency, other multiple pregnancies, such as three cases actually tripled. This result is actually due to the help of assisted reproductive technology. According to incomplete statistics from our Ministry of Health, a large proportion of our population suffers from infertility for various reasons, accounting for one eighth of women of childbearing age, or nearly 50 million women of childbearing age with problems in getting pregnant. Assisted reproductive technology has brought hope to this population, but when it comes to assisted reproduction, or IVF, the natural success rate is still relatively low. How can assisted reproduction technology increase the success rate? In fact, as long as two more embryos are implanted, the success rate will be much higher. Therefore, in the process of IVF, domestic and foreign institutions will implant more than one embryo into a woman’s uterus to increase the success rate of conception, and this method will indirectly increase the possibility of conceiving a double pregnancy, so the chance of conceiving a double pregnancy can reach 25%-30% in the population of assisted reproduction. In addition, ovulation promotion may also increase the likelihood of conceiving twins. Under normal circumstances, assisted reproduction uses ovulation promotion to obtain multiple eggs and increase the likelihood of conception. What is the difference between identical and dizygotic twins in twin pregnancies? Some twins are formed when the mother’s two eggs combine with different sperm to form two embryos, which is known as dizygotic twins. Is there a difference between dizygotic and monozygotic babies? Generally speaking, monozygotic twins and dizygotic twins are genetically related. Monozygotic twins may be formed because the mother is more likely to have a genetic predisposition to carry twins, while dizygotic twins are common in assisted reproduction where multiple implanted embryos develop successfully. Because dizygotic twins develop from two fertilized eggs, their genetic backgrounds are similar but the DNA sequences may be slightly different, and the degree of genetic similarity is similar to that of non-twin siblings, so such children generally have similar physical characteristics and may have the same or different sex and blood types. Monozygotic twins, on the other hand, have basically the same genetic material, so such children have exactly the same sex and blood type, and their physical appearance is also very similar. It is difficult to know the nature of the twins before delivery, but doctors can estimate the nature of the chorionic villus. What is the nature of the chorionic villus of a twin baby? Why is there a classification of DCDA, MCDA and MCMA in intrauterine twins? Both the placenta and the amniotic sac are fetal appendages, and the above-mentioned typing is based on the different conditions of the chorionic villus and amniotic sac in twin pregnancies. In general, all dizygotic twins, which account for 70% of twin pregnancies, are DCDA (double chorionic villus and double amniotic sac) twins, and the prognosis for this group of twins is very good. There is another group of twins, about 30%, which are monozygotic twins. In this group of twins, there may be DCDA (double chorionic membrane with double amniotic sac), MCDA (single chorionic membrane with double amniotic sac), and MCMA (single chorionic membrane with single amniotic sac) because of the different nature of the chorionic membrane. The focus of the doctor’s attention is on the MCDA (monochorionic double amniotic sac) part of the twin fetus because of the complex complications that can occur. The first point to make is why do dizygotic twins have only one condition, DCDA, while monozygotic twins can have multiple conditions such as MCDA? This is because dizygotic twins develop directly from two fertilized eggs each, and therefore have two separate sets of fetal accessory structures. The earlier the embryo divides, the better the degree of independence of the two fetuses, that is, the earlier the division is more likely to be DCDA (double chorionic membrane with double amniotic sac), while the later the division is the more likely to be MCDA (single chorionic membrane with double amniotic sac) or MCMA (single chorionic membrane with single The later the division, the more likely it is to be MCDA (monochorionic double amniotic sac) or MCMA (monochorionic single amniotic sac) and even conjoined twins may occur if the division occurs after 13 days.