Often patients find just a very small amount of vaginal bleeding when they should have their period. I usually tell them that they may be pregnant and immediately take an early pregnancy test and learn that they are pregnant. When vaginal bleeding (commonly known as redness) occurs after pregnancy, pregnant women are usually very nervous and immediately think that they are having a preterm miscarriage. In fact, a small amount of vaginal bleeding in early pregnancy may be normal or abnormal. The normal situation is bleeding from implantation, the fertilized egg divides several times to form the blastocyst into the uterine cavity, under the action of hormones and many cytokines, similar to the erosion of the uterine meconium, the differentiation of trophoblast cells in the villi on the surface of the gestational sac, part of which erodes into the uterine meconium and part of the muscular layer, and finally the formation of the placenta, which provides all the exchange channels and places for oxygen and nutrients needed for the growth and development of the fetus, this process if there is A small amount of bleeding will occur if there is damage to the neovascularization. Abnormalities include miscarriage (preterm, indolent, incomplete and complete) and ectopic pregnancy (commonly known as ectopic pregnancy). Of these, preterm miscarriage has the potential to continue the pregnancy with treatment, while the other cases are pregnancy failures, the majority of which require medical intervention. Bleeding from implantation, preterm miscarriage, indolent miscarriage, and ectopic pregnancy are usually low and are usually determined by the physician based on history, ovulation, days of menopause, amount of vaginal bleeding, size of the uterus, ultrasonography, and blood HCG measurement; some cases are so typical that they are sometimes not immediately identified and the patient is instructed to follow up. Generally speaking, two weeks after ovulation (if the estimation is based on the last menstrual period, it needs to be combined with the length of the menstrual cycle, which corresponds to when the next menstrual period should come), the early pregnancy test may detect a positive result, when the blood HCG level is around 100-300 IU/L, while the gestational sac in the uterine cavity can be detected by ultrasonography, usually at around 2000 IU Early intrauterine pregnancy is determined (depending on the ability of the physician and the resolution of the ultrasound), this time frame is about 3-4 weeks after ovulation (5-6 weeks according to the last menstrual period), ectopic pregnancy is mostly diagnosed clinically by the exclusion method, no intrauterine pregnancy is detected and the blood HCG reaches a certain standard The diagnosis of ectopic pregnancy is made in the absence of intrauterine pregnancy and in the absence of intrauterine pregnancy. In less than 10% of ectopic pregnancies, an extrauterine gestational sac or an abnormal echo of abundant blood flow in the adnexal region may be detected. The first determination of intrauterine viability in early pregnancy is based on primitive fetal heart tube beats, which can be detected by ultrasound at approximately 7-8 weeks (from the last menstrual period). Incomplete and complete miscarriages usually have more bleeding, equal to or more than the menstrual flow, especially in incomplete miscarriages, when there is tissue embedded in the cervical os that cannot be expelled smoothly, affecting the uterine contractions resulting in bleeding that may put the patient in shock and require immediate emergency curettage. There is a period of uncertainty after the blood or urine HCG indicates pregnancy until the ultrasound detects intrauterine pregnancy, and there is a period of uncertainty from the ultrasound detects intrauterine pregnancy until the fetal heart is detected, which cannot overcome the diagnostic vacuum stage according to the current medical equipment and technology. Firstly, timely ultrasound examination can determine intrauterine pregnancy at 5-6 weeks of pregnancy to exclude ectopic pregnancy, and if no gestational sac is found, vigilance should be raised and short-term follow-up can prevent to some extent the possibility of rupture and hemorrhage due to untreated ectopic pregnancy; secondly, the examination and follow-up of HCG, as individual differences in HCG levels are large, it is very meaningful to make your own control. A value of two days apart is valuable for clinical diagnosis. In fact, the ultrasound dose and time used for diagnosis are not harmful to the fetal development, but it is more than worthwhile to worry about it without timely and effective examination, which may lead to more serious consequences. There is also a problem with the use of birth control drugs, generally speaking, birth control drugs refer to a variety of progesterone preparations that can be used to treat luteal insufficiency in pregnancy. Strictly speaking, it has therapeutic value only for luteal insufficiency of pre-eclampsia, but it is not effective for those not caused by this reason. There is no academic consensus on this. If luteal insufficiency may be the result of follicular dysplasia, treatment with progesterone does not improve the prognosis, even if luteal insufficiency is present. However, in general, those with low progesterone measurement can be treated with progesterone along with ultrasound to dynamically observe the embryonic development and stop the medication if embryonic arrest is detected. So don’t be nervous about seeing red in early pregnancy, take a calm mind and actively cooperate with the diagnosis and treatment.