Many people want to have twins and want to put more embryos in to improve their chances of getting pregnant. Is it right to come for IVF just for twins? Is putting more embryos really beneficial for infertility patients? The birth of IVF technology was a great milestone in the history of medicine, and millions of IVF babies have been delivered worldwide, bringing joy and happiness to countless families. However, along with the rapid spread of IVF technology and the remarkable increase in success rates, problems such as multiple pregnancies have become increasingly prominent, causing widespread concern in the medical community. Surveys have shown that the dramatic increase in the rate of multiple pregnancies worldwide over the past 30 years is inextricably linked to the widespread use of assisted reproductive technologies, with 70% to 90% of multiple pregnancies associated with ovulation and IVF, mainly due to the hope of doctors and patients to induce multiple mature follicles at once and transfer multiple embryos to improve the chances of pregnancy. In fact, perinatal studies have long demonstrated that multiple pregnancies are strongly associated with poor maternal-fetal outcomes. From the perspective of reproductive physiology, human reproduction is a singleton pregnancy, and the female reproductive system is naturally designed for the growth and development of only one fetus, and any disruption of this conventional “design” will have multiple adverse effects on both mother and fetus. The “natural design” of the female reproductive system is designed for the growth and development of only one fetus. Multiple pregnancies place a significant physical and psychological burden on the mother, making the long gestation process a risky one and leading to a series of serious consequences in case of failure of vital organ function. Compared to singleton pregnancies, multiple pregnancies are associated with a significantly higher risk of gestational anemia, gestational diabetes, and amniotic fluid overload; a twofold and fivefold higher risk of preterm delivery and preeclampsia-eclampsia, respectively; up to 86% of multiple pregnancies requiring cesarean delivery; and significantly higher obstetric hemorrhage and maternal mortality. Multiple pregnancies are also not good news for the fetus, as multiple fetuses competing for and affecting each other in the limited uterine cavity can lead to poor obstetric outcomes. Studies have demonstrated that approximately 50% of twin pregnancies end in spontaneous abortion (as exemplified by the recent early abortion of Hong Kong singer Kelly Chen’s IVF twin pregnancy), preterm birth is extremely common, birth weight is generally low, and the risk of congenital malformations, mental retardation, and disability is increased two to three times, which in turn leads to a dramatic increase in neonatal mortality. The increased prevalence of maternal and infant morbidity leads to significantly higher medical costs than singleton pregnancies, which places a heavy burden on families and society. These alarming statistics remind us that the ultimate goal of IVF is not just to obtain a pregnancy, but to deliver a physically and mentally healthy child. As a result, multiple pregnancies are actually a complication of IVF technology that women of childbearing age cannot afford, and at the 2010 European Annual Conference on Human Reproduction and Embryology, experts put forward the slogan that a singleton pregnancy is a success, a double pregnancy is a failure, and a triplet pregnancy is a disaster. Therefore, if doctors are asked to take IVF to assist pregnancy just for the sake of having twins, it is actually at the cost of seriously affecting the health of mothers and babies, which is just like putting the cart before the horse and will certainly be opposed by reproductive medicine practitioners. Therefore, China’s Ministry of Health has formulated and promulgated strict indications necessary for IVF treatment, which all reproductive medicine centers are required to strictly grasp and effectively implement. Formal treatment to reduce multiple pregnancies In order to minimize the occurrence of multiple pregnancies, it needs to be controlled from several angles. First, the misuse of ovulation-promoting drugs must be strictly controlled. In recent years, there has been an increasing trend of high-sequence multiple pregnancies (triplet pregnancies and above) due to self-administration and use of ovulation drugs by non-fertility specialists, and news about quadruplets and quintuplets has been reported in the media. It is important for couples intending to conceive to understand that ovulation-promoting drugs (commonly known as “multiples”) are only indicated for women with ovulation disorders, and that women without ovulation disorders should never use ovulation-promoting drugs as a panacea for having multiple pregnancies. Abuse of “multi-baby pills” may not only increase the chance of multiple pregnancies, but may also lead to ovarian hyperstimulation syndrome and even infertility, and in serious cases may lead to hematuria, ascites, liver and kidney failure and even death. In my clinical work, I once saw a woman who had five pregnancies after taking ovulation promotion drugs on her own develop severe ovarian hyperstimulation syndrome, and eventually all the fetuses were aborted and the mother almost died due to postpartum hemorrhage. The guidelines issued by the Reproductive Medicine Branch of the Chinese Medical Association clearly state that doctors without formal training in reproductive medicine should not prescribe ovulation-promoting drugs and prohibit ovulation-promoting treatment in units without ultrasound and serum sex hormone testing. Therefore, patients with infertility should undergo ovulation promotion treatment at a reproductive medicine center established by a regular hospital with the approval of the health administration. In addition, the specialist in reproductive medicine should strictly control the indications for ovulation promotion and embryo transfer. The American Society for Reproductive Medicine states that if more than 4 mature follicles are found during the course of routine ovulation promotion-guided intercourse, the cycle should be terminated and the patient should be required to use strict contraception. In China, the Ministry of Health issued a regulation back in 2001 that requires women under 35 years of age and undergoing their first IVF treatment to implant 2 embryos at a time, while women over 35 years of age or undergoing the technique for the second time can implant up to 3 embryos at a time. Since 2010, single embryo transfer has been fully implemented in the UK, with a strict requirement that only one embryo be transferred in any case for women under the age of 40. Some patients may be concerned whether limiting the number of embryos transferred will result in lower pregnancy rates. In fact, with the current rapid improvement in IVF technology, a significant number of fertility centers have achieved pregnancy rates of 50%, with individual centers of excellence reaching even higher rates of 60% to 65%. Studies have shown that reducing the number of embryos transferred at high level fertility centers not only does not lead to a significant decrease in pregnancy rate, but also helps to increase the live birth rate and reduce the incidence of preterm birth and neonatal malformations. Finally, what happens in case of multiple pregnancies? The technical specifications for assisted reproduction promulgated by the Ministry of Health in 2003 clearly require that multiple pregnancies after the use of assisted human reproduction techniques must be reduced, avoiding twin pregnancies and strictly prohibiting the delivery of three or more pregnancies. Therefore, infertile couples are required to sign the Consent Form for Reduction of Multiple Pregnancies before undergoing IUI and IVF treatment. The procedure is performed preferably at 6-8 weeks of gestation and is preceded by the routine administration of intramuscular analgesic drugs. The target sac is aspirated by fine needle puncture under the guidance of vaginal ultrasound, and the excess embryos are killed by mechanical strangulation or local injection of drugs, preserving one to two normal fetuses. Some centers are now recommending reduction for twin pregnancies. We recommend that patients with previous history of preterm labor, habitual miscarriage, septate uterus, unicornuate uterus, double uterus and cervical insufficiency be actively considered for early pregnancy reduction to preserve only one fetus for the benefit of these patients to eventually achieve a healthy near-full-term newborn.