By 20 weeks of pregnancy, the typical weight gain varies depending on your pre-pregnancy weight and BMI, but general guidelines are as follows:

• In the first trimester (up to about 13 weeks), most women gain between 0 to 5 pounds (0 to 2.3 kg), sometimes even losing weight due to morning sickness

• During the second trimester, which includes week 20, weight gain usually accelerates. Between weeks 14 to 17, you might gain about half a pound per week (totaling 2 to 3 pounds), and from weeks 18 to 22, up to 1 pound per week is common, potentially reaching about 4 pounds in this period

• By the end of week 20, it is typical to have gained up to around 10 pounds (about 4.5 kg), though this can vary

• Overall, most women gain between 10 to 12.5 kg (22 to 28 pounds) over the entire pregnancy, with much of the weight gained after week 20

• Weight gain recommendations depend on pre-pregnancy BMI:
  • Healthy weight (BMI 18.5–24.9): total gain of about 11.5 to 16 kg (25 to 35 pounds)
  • Underweight (BMI <18.5): more weight gain recommended
  • Overweight or obese: less weight gain recommended

• The weight gain during the second trimester is typically about 1 pound (0.5 kg) per week for women starting at a healthy weight

In summary, by 20 weeks, a healthy weight gain is usually around 8 to 10 pounds (3.5 to 4.5 kg), with variations based on individual factors such as BMI and pregnancy health. It is best to consult your healthcare provider for personalized guidance.