Pregnancy is a major event in a woman's life. During pregnancy, in order to ensure the healthy development of the fetus, pregnant women change many bad habits, quit their favorite foods, and refrain from doing many things they enjoy. Because at this time, pregnant women are most worried about fetal malformations. So when is the most likely time for pregnancy to cause malformations?
Generally, fetal malformations are most likely to occur during the 5-10 weeks after pregnancy (counted from the last menstrual period) due to external environmental or drug factors. This period is also known as the teratogenic sensitive period because the fertilized egg is forming and differentiating into the fetus. During the 3-4 weeks of the last menstrual period, if the embryo is less affected, it can generally develop normally. If it is more severely affected, it can cause miscarriage.
During the 11-40 week period of the last menstrual cycle, the embryo is often affected by adverse factors, which can cause fetal dysfunction, but the incidence of malformations is relatively low. However, pregnant women should maintain sensitivity to teratogenic factors until late pregnancy, because being affected in late pregnancy may also affect fetal intellectual development. Therefore, from the perspective of eugenics, eugenics protection should be provided to the fetus throughout the entire pregnancy period.
Preventing birth defects should start before marriage and pregnancy, especially with proper preventive care during pregnancy. Some birth defects can be prevented through interventions such as eugenics counseling, avoiding harmful factors, chromosome testing, TORCH testing, vaccination, and nutrient supplementation.
