“Doctor, I’m pregnant, but I didn’t know I was pregnant before I took a cold pill just now, can I have this baby?” “I have hyperthyroidism, now I am pregnant, do I need to stop taking the medicine?” These questions are frequently asked by obstetricians and gynecologists, and they are also a frequent concern for new mothers. The first thing we need to know about medications during pregnancy is the “all or nothing” benefit, which means that within 2 weeks of fertilization, the effect of the medication on the embryo will either result in the miscarriage of the baby or it will have no effect on the baby and there will be no problems with the baby. Fertilization usually occurs in the middle of menstruation, if menstruation is once every 28 days then the all or nothing benefit is probably within a month of menstruation, if you take the drug without knowing you are pregnant, you don’t have to be too nervous, if the child survives then there is usually no problem. There are a lot of people who find out that they are pregnant after taking the emergency contraceptive pill (Yutin) and are adapted to this pattern, which means that if they want to have a child, they can go ahead and have it. Then, after 2 weeks, whether the drug has an effect on the child, we will probably need to understand the U.S. Food and Drug Administration (FDA) for the drug’s pregnancy classification. To indicate whether a drug has an effect on an embryo, you need to look at its results on animal tests and human studies.The FDA categorizes all drugs into A/B/C/D/X categories. The FDA classifies all drugs as A/B/C/D/X. Almost any drug can be searched for its FDA classification, and once we know the classification, we can answer the patient’s question. For example, a friend told me that she had irregular periods, found out she was pregnant at 40 days after menopause, and took Furadantin tablets at about 35 days to treat a urinary tract infection, and asked if she could continue to have children. Because of irregular menstruation, you can use ultrasound to determine the pregnancy week first, if the actual pregnancy week is less than 4 weeks (we calculate the pregnancy week from the last menstruation), then there is no problem, if we don’t know the current pregnancy week, or if the current pregnancy week is more than 4 weeks, then we need to look up the classification of the gestation period of furandamidine. After checking the domestic information, we did not find any FDA pregnancy classification of Furadantin, which is indicated by “use with caution” in the instruction manual of the drug. It doesn’t matter whether it’s in the second week of gestation or not, class B drugs are safe throughout pregnancy. Similarly, in patients with comorbidities prior to pregnancy, such as hyperthyroidism, is it necessary to continue the medication during pregnancy? Let’s look up propylthiouracil (commonly known as propyzine), a class D drug, which is a potential risk to the fetus, but if the hyperthyroidism is uncontrolled and the effect of the hyperthyroidism disease itself on the mother and the child outweighs the effect of the medication on the child, then at this point it is necessary to consider continuing the medication to control the hyperthyroidism during the pregnancy unless the hyperthyroidism is under control, and the physician advises that the medication can be left in place for observation. Of course things can change during pregnancy, some patients get worse during pregnancy and others go into remission, so patients with comorbidities during pregnancy often require a multidisciplinary approach to managing the patient and making decisions about medication. The same reasoning applies to a common condition such as having a cold. There are no results from rigorously designed clinical trials of herbal or proprietary medicines, so the effects on the embryo cannot be evaluated using FDA classification criteria, which is a deficiency, so you have to ask me if you can have a baby, and I don’t know how to answer you. If the baby is precious just wait until about 20 weeks for a teratology screen to see if there are any problems, and if there are no problems then go ahead. Drugs are an all or nothing effect in early pregnancy and a similar all or nothing effect exists when you get an x-ray within 2 weeks of conception.