Vaginal bleeding during pregnancy is a common clinical phenomenon that can cause anxiety and concern for the pregnant woman and even the whole family, especially for those with a history of adverse births, such as a history of early miscarriage or a poor prognosis for the newborn. So, how to deal with this situation? Is vaginal bleeding always abnormal? What are the causes of vaginal bleeding? Does vaginal bleeding always cause a miscarriage? How to treat it? Today we are going to talk about vaginal bleeding. First of all, it is important to understand the stages of pregnancy, which are usually divided into early pregnancy (before the end of the 13th week), middle pregnancy (from the end of the 14th to the 27th week) and late pregnancy (from the 28th week and after). Vaginal bleeding in mid- and late pregnancy is more commonly associated with abnormal placental position (e.g. placenta praevia) or early placental abruption (abruptio placenta), although other placental-fetal factors such as sail attachment of the umbilical cord, rupture of the anterior vessels, and rupture of the blood sinus at the placental margin may also be involved. Cervical lesions are less common. 1. Causes of vaginal bleeding in early pregnancy Vaginal bleeding occurs in 20-40% of women in early pregnancy and often originates from the mother rather than the fetus. There are many causes of bleeding, including pregnancy-related ones, which are the most common concerns, such as miscarriage, ectopic pregnancy (commonly known as ectopic pregnancy, which is replaced by ectopic pregnancy in order to comply with the full text of the habit) and gestational trophoblastic disease (e.g., the familiar one is staphyloma); and some inflammatory diseases of the reproductive tract, such as cervicitis, cervical polyps, vaginitis or tumors of the reproductive tract (e.g., cervical cancer). Of course, there is also the normal case of rupture of the maternal meconium vessels during fertilization of the egg, which can also cause a small amount of vaginal bleeding. In other words, vaginal bleeding originates from different sites and can be divided into vaginal bleeding, cervical bleeding, and uterine bleeding. More often than not, it is not from the vagina but from the uterine cavity, and the bleeding associated with miscarriage is also from the uterine cavity, but everyone is used to calling it vaginal bleeding. Vaginal bleeding can be normal or abnormal, normal being a transient small amount of vaginal bleeding due to fertilization of the egg, and abnormal being due to the various causes mentioned above. In early pregnancy, 15%-20% of people who bleed will miscarry, while ectopic pregnancy accounts for a relatively small percentage, about 2%, and about 0.2% for gravidity. Do you think this is a high percentage, but in fact, this population includes some inevitable miscarriages, incomplete miscarriages and after complete miscarriages. If we refine it more, for those who have a viable intrauterine embryo confirmed by ultrasound at 7-11 weeks, with a closed uterine orifice and showing only a small amount of vaginal bleeding, 90-96% will not miscarry and the vast majority can continue the pregnancy. Summary: Vaginal bleeding can occur in 20-40% of the population in early pregnancy, and 90%-96% of preterm abortions in the above-mentioned limited population can continue the pregnancy; the bleeding is more related to miscarriage, so the site of bleeding should be clarified first; there are normal and abnormal bleeding, and the rupture of small vessels in the maternal meconium during fertilization can also cause a small amount of vaginal bleeding. 2. Diagnosis of vaginal bleeding in early pregnancy Even though, as mentioned earlier, vaginal bleeding in early pregnancy is relatively common and may be normal or may only be a small amount of bleeding caused by cervical polyps, the condition should not be ignored and must be evaluated at the earliest possible time. The purpose of the evaluation is, first, to quickly determine the amount of bleeding, based on the pregnant woman’s symptoms such as dizziness, panic attacks, the size of the clot or the amount of bleeding described by the pregnant woman, and the amount of clothes soaked through, etc. Second, to try to find the cause of the bleeding and to rule out ectopic pregnancies that can threaten the life of the pregnant woman. The assessment process is the process of doctor’s visit, which, broadly speaking, means that the doctor first asks about the medical history to find out if there are any high-risk factors. For example, if there is a history of pelvic inflammatory disease or ectopic pregnancy, then the pregnancy is considered ectopic. Next, a physical examination and vaginal examination will be performed to generally identify the cause and location of the bleeding, and some localized vaginal and cervical bleeding can be detected by vaginal speculum examination. The purpose of ultrasound examination is to determine the location of the gestational sac, whether the pregnancy is intrauterine or ectopic, and whether a fetal heart is present. Once the ultrasound confirms an intrauterine pregnancy and the presence of a fetal heart, it is usually not necessary to monitor the change in the level of preterm abortion in early pregnancy bleeding when the intrauterine embryo is confirmed to be alive by ultrasound and the opening of the uterus is not yet open. In general, the normal rise in blood β-HCG level is about 35% increase in 48 hours. When intrauterine pregnancy cannot be diagnosed after 6 weeks of menopause or when blood β-HCG is greater than 2000 IU/L, we should be highly alert to the occurrence of ectopic pregnancy and continue to monitor its changes. However, it is also important to know that a decrease in β-HCG does not necessarily mean ectopic pregnancy, as about 21% of ectopic pregnancies can also present with normal β-HCG levels. Some pregnant women question the safety of vaginal exams and vaginal ultrasound in early pregnancy, but there is really nothing to worry about, as there is a large body of evidence that ultrasound is safe in early pregnancy. There are many benefits of ultrasound in early pregnancy, such as assisting in ruling out ectopic pregnancy, confirming the development of the embryo and the presence of a fetal heartbeat, identifying gravidity, detecting the disappearance of one of the twin fetuses, and assisting in calculating the due date later on. Vaginal examination is not necessary to say, you say, let the doctor open the vagina to take a look will abort? But some moms just obsess over it. Some pregnant women are obsessed with how many indicators they should have after pregnancy. To be honest, without high risk factors and vaginal bleeding, these indicators are not usually checked by doctors. Let’s set out a table to give you an idea. In case of vaginal bleeding, seek early medical attention. Your doctor will assess the amount of bleeding, try to find the cause of the bleeding and rule out ectopic pregnancy so that the next course of management can be decided. Current evidence suggests that vaginal ultrasound is safe, combined with blood beta-HCG level monitoring to assist in determining the condition if necessary. Treatment of vaginal bleeding in early pregnancy is mainly directed at the cause, for example, if ectopic pregnancy has been identified, the treatment will follow the principles of diagnosis and treatment of ectopic pregnancy. Here we are going to talk about the vaginal bleeding associated with miscarriage, which is the one that we are most concerned about. First of all, once again, it is clear that more than 50% of those who bleed in early pregnancy can continue the pregnancy, and up to 96% can continue the pregnancy if the embryo is confirmed alive by ultrasound at 7-11 weeks, the opening of the uterus is not yet open, and there are only symptoms of preterm miscarriage. In a prospective study published in 2010, 12% of 4000 pregnant women with vaginal bleeding in early pregnancy miscarried, while 13% of those without vaginal bleeding in early pregnancy also miscarried. I know the main concern is not the cause and diagnosis of the bleeding, or what interventions are needed to help ensure that the baby grows up well. For a mother, that’s the most important thing. But many times, we are still helpless. The etiology of miscarriage is complex, including fetal factors, maternal factors, unknown causes, etc., which can be described as fancy, but the most important part is fetal chromosomal abnormality, which was previously reported to account for about 50% of the causes of miscarriage, but with the advancement of embryonic chorionic villi chromosome testing technology, more chromosomal abnormalities will be detected, and there are even reports in the literature that the proportion is as high as about 70%. In other words, spontaneous miscarriage in early pregnancy should be a “good thing”, a kind of superiority and inferiority of nature. As you can imagine, there are no effective measures to intervene in this population. So, you may ask whether progesterone is useful or not. Experts and professors are saying that progestins are useless, but why are they still widely used in clinical practice? It is true that the current evidence does not recommend the widespread use of progestogen in early pregnancy, and even in the case of luteal deficiency, i.e. insufficient progesterone production, much of the foreign evidence does not recommend supplementation, mainly for the reason that the diurnal variation and pulsatile secretion make blood progesterone testing unreliable. Clinically, we have also encountered cases with repeated low progesterone and repeated supplementation still relatively low but with good outcome. Of course, one cannot use individual cases to speculate on conclusions. Nowadays, the clinical use of progesterone in China is more often seen in people who do have high-risk factors, such as those who have recurrent or habitual miscarriages, because it has been suggested in the literature that it can effectively inhibit maternal immune rejection of the embryo and increase uterine artery blood flow; for example, those who have low progesterone levels in vaginal bleeding during pregnancy. Of course, there is also a part of the reason attributed to the doctor-patient environment, in the principle of “no harm to the patient”, considering that the use of natural progestins during pregnancy is safe and has a comforting effect on the patient’s heart, and taking a step back, if not the use of drugs may cause disputes, these are factors that doctors have to consider. There is another important reason to also consider the cost of time and money for the patient, preferring to intervene more as long as it increases even the success rate, after all, many pregnancies are not easy. In any case, it is important to grasp the medical principles and try to do something that is supported by evidence, something that is really beneficial to the patient, provided of course that the principle of “do no harm” is applied. In conclusion: vaginal bleeding in early pregnancy does not necessarily mean miscarriage, nor does the absence of bleeding mean non-miscarriage; vaginal bleeding in early pregnancy increases the risk of preterm delivery, premature rupture of membranes, placental abruption and fetal growth restriction; the risk of miscarriage increases with the amount and duration of vaginal bleeding; the cause of miscarriage in early pregnancy is more than 50% and even more than 70% have been reported to be fetal chromosomal abnormalities; there is no very effective intervention for vaginal bleeding in early pregnancy. There are no very effective interventions for vaginal bleeding in early pregnancy; progestogen supplementation may be beneficial for some high-risk groups, but abuse is not recommended.