The amount of weight you should gain during pregnancy depends primarily on your pre-pregnancy body mass index (BMI) and whether you are carrying one baby or multiples.
General Guidelines for Weight Gain During Pregnancy
- Normal weight (BMI 18.5–24.9): Gain about 25 to 35 pounds (11.5 to 16 kg). Most women gain 2 to 4 pounds (1 to 2 kg) in the first trimester, then about 1 pound (0.5 kg) per week for the rest of the pregnancy
- Underweight (BMI < 18.5): Gain more, around 28 to 40 pounds (12 to 18 kg)
- Overweight (BMI 25–29.9): Gain less, about 15 to 25 pounds (7 to 11.5 kg)
- Obese (BMI ≥ 30): Gain even less, roughly 11 to 20 pounds (5 to 9 kg)
For Twin Pregnancies
- Women of normal weight carrying twins should gain 37 to 54 pounds (16.5 to 24.5 kg)
- Overweight women carrying twins: 31 to 50 pounds (14 to 23 kg).
- Obese women carrying twins: 25 to 42 pounds (11 to 19 kg)
Weight Gain Breakdown
Much of the pregnancy weight gain is due to the baby and supporting tissues, not just fat:
- Baby: ~8 pounds (3.5 kg)
- Placenta: 2 to 3 pounds (1 to 1.5 kg)
- Amniotic fluid: 2 to 3 pounds (1 to 1.5 kg)
- Breast tissue: 2 to 3 pounds (1 to 1.5 kg)
- Blood supply: 4 pounds (2 kg)
- Fat stores: 5 to 9 pounds (2.5 to 4 kg)
- Uterus growth: 2 to 5 pounds (1 to 2.5 kg)
Caloric Needs During Pregnancy
- 1,800 calories/day in the 1st trimester
- 2,200 calories/day in the 2nd trimester
- 2,400 calories/day in the 3rd trimester
Monitoring Weight Gain
- Weigh yourself about once a week, at the same time and under similar conditions to track progress without stress
- Adjustments may be needed based on your health and pregnancy progress; always consult your healthcare provider for personalized advice.
In summary, aim for weight gain tailored to your pre-pregnancy BMI, with typical targets ranging from about 11 to 40 pounds depending on your weight category and whether you are carrying multiples
