If you are pregnant for one month and do not know that you have had intercourse, you do not need to worry if there is no vaginal bleeding, abdominal pain in the lower abdomen, etc. It will not affect the growth and development of the embryo. In order to be safe you need to do regular pregnancy tests, blood HCG measurement, negative or abdominal ultrasound to see the development of the gestational sac. Fetal heart and buds can be detected around 50 days of pregnancy, so as long as the embryo develops normally there is no need to worry. However, if vaginal bleeding occurs after coitus, it is considered to be an aura of miscarriage, and HCG needs to be detected, and progesterone needs to be taken in time to protect the fetus, and at the same time, it is recommended to take bed rest, and reasonable supplementation of vitamin E, which also has the effect of preserving the fetus. After the occurrence of preeclampsia, you need to adhere to the birth control until after the third month of pregnancy, because after the third month of pregnancy, the development of the fetus is relatively stable, and the chances of having another miscarriage are reduced. Early pregnancy fetal development is not stable, it is best not to cohabitate, but also can not eat cinnamon, barley, crabs and other foods, will cause the possibility of miscarriage, it is recommended to eat more vegetables, fruits, and to maintain a smooth bowel movement, but also reduce the possibility of miscarriage.