17 + 1 means 17 weeks + 1 day of pregnancy, which generally means more than 4 months of pregnancy. Pregnancy is counted from the last menstrual period, every 7 days is counted as a week, every 4 weeks is counted as a month, the whole pregnancy is about 40 weeks, i.e. 280 days, so 17 weeks + 1 day refers to 4 months of pregnancy more than 1 week and 1 day. At this stage of the pregnancy belongs to the middle, need to carry out timely obstetric examination, this period is mainly to do is the Down’s syndrome screening or non-invasive DNA testing to rule out fetal chromosomal malformations. During this period, pregnant women should pay more attention to rest, strengthen nutrition, pay attention to a balanced diet, and pay attention to observe the fetal movement, usually appropriate walking, more sunshine, and if there are symptoms of discomfort, it is recommended to consult a doctor in a timely manner.