After pregnancy, mothers-to-be are the most worried, confused and concerned about miscarriage and birth control. The author has been practicing medicine for more than 20 years and has encountered too many bizarre stories and outrageous practices that make me feel both helpless and speechless. The normal miscarriage rate is 15% In order to give you a proper understanding of miscarriage and birth control, the author first tells you some basic facts about pregnancy and miscarriage: in the whole female population, the total miscarriage rate of clinical pregnancy is about 15%, and if biochemical pregnancy is also counted, the total embryo loss rate is as high as 60% to 70%. Of all the embryos conceived, only about 1/3 are transformed into viable newborns. A biochemical pregnancy is one in which the miscarriage occurs very early in the pregnancy, without the woman being aware of it, and may not show any signs at all, but at most a slight delay in menstruation for a few days and a slightly heavier period. Pregnancy is actually a process of trial and error, natural selection and natural elimination. The most important cause of spontaneous miscarriage is chromosomal abnormality of embryo, the proportion is about 50%; other causes include maternal factors, including anatomical abnormalities of reproductive organs, autoimmune factors, infectious factors, endocrine factors, unexplained factors (including thrombotic tendency, etc.), but the proportion of miscarriage caused by lack of progesterone level due to luteal insufficiency is very small. It is not reliable to use progesterone levels to guide birth control The clinical reason for testing progesterone levels is that one of the causes of miscarriage is luteal insufficiency (a small percentage), which can lead to low progesterone levels and further lead to miscarriage. If detected in time, progesterone can be supplemented to prevent miscarriage from occurring. The gold standard for the diagnosis of luteal insufficiency is an endometrial biopsy at mid-luteal phase, but since two consecutive endometrial biopsies are required to diagnose luteal insufficiency, it is almost impossible to use the gold standard for diagnosis in clinical practice. Therefore, it has been proposed to test progesterone levels to determine luteal function, but this method is not reliable because – 1, progesterone levels in normal pregnancy fluctuate widely. 2, low progesterone levels are more likely to be the result of poor embryonic development rather than a cause to be miscarried. 3, Half of the patients diagnosed with luteal insufficiency have normal progesterone levels. 4. In early pregnancy, there are two sources of progesterone: one is secreted by the corpus luteum and the other by the trophoblast. We cannot tell which one is responsible for the low level. Therefore, it is not recommended to routinely measure progesterone levels to guide fetal preservation. Of course, the usefulness of progesterone testing cannot be dismissed in general. After a positive test for HCG (human chorionic gonadotropin), when ultrasound does not reveal evidence of pregnancy, progesterone level testing is still helpful in determining the prognosis of pregnancy, and low levels of progesterone mean that miscarriage and ectopic pregnancy are more likely. But the purpose of progesterone testing is definitely not to supplement progesterone. Bed rest to protect the pregnancy is just mental comfort Even if you repeat that there is no evidence-based medical evidence that bed rest can reduce the incidence of miscarriage, there are still many mothers-to-be, especially their mothers and mothers-in-law, who simply won’t listen. One of the most bizarre cases I’ve seen is a daughter who had a spontaneous miscarriage in her first pregnancy and then was absolutely bedridden after her second pregnancy, eating, drinking, pooping, and spilling all in bed and not allowed to go down for 6 months. By the time the mother brought her daughter to the clinic, she was already walking wobbly and the examination revealed that the muscles of her lower limbs had atrophied significantly. This practice is simply outrageous. In fact, without evidence-based medical evidence, common sense should be able to tell that bed rest to preserve the pregnancy is not working. Nearly half of all miscarriages are caused by chromosomal abnormalities of the embryo, and this situation is doomed to miscarriage no matter what you do, not to mention bed rest, even if you play progesterone every day is useless. Is it good to keep a fetus that falls off when walking or sneezing? If the fetus will fall off when you walk, the hospital’s family planning clinic can be closed, no more abortion, let everyone walk or even run, it can replace the scraping. Progesterone for miscarriage preservation WHO does not recommend The latest Cochrane review on progesterone for miscarriage prevention published in 2013 (the most authoritative evidence-based medicine) concluded that the application of progesterone (either intramuscular or oral) is ineffective in preventing miscarriage; for 3 or more consecutive spontaneous abortions, empirical progesterone supplementation may be beneficial, but this requires large samples of multicenter studies to further confirm. The World Health Organization also does not recommend the use of progesterone for fetal preservation, see WHO website. Of course, progesterone supplementation is needed in a few cases, such as patients who have had their corpus luteum surgically removed during early pregnancy and some patients undergoing IVF (in vitro fertilization) whose progesterone levels have dropped due to surgical procedures.