Twin pregnancy
Twin Pregnancy Weight Gain Planner
Twin pregnancies require higher caloric and nutrient support than singleton pregnancies. Enter your pre-pregnancy data and current progress to see recommended gain ranges from the Institute of Medicine.
Pre-pregnancy BMI
25.7
Target the lower range (14–22.7 kg) while ensuring nutrient density.
Current gain
10.0 kg (10.0 kg)
Target ranges
- Total recommended gain: 14.0 – 22.7 kg (14.0 – 22.7 kg)
- Expected gain by 24.0 weeks: 6.4 – 10.4 kg (6.4 – 10.4 kg)
How to Use This Calculator
Collect accurate baseline data
Use pre-pregnancy weight and measured height to compute BMI. Accurate trends require consistent weighing conditions.
Compare actual gain with targets
Use trimester-adjusted ranges to assess whether you are on track, above, or below recommendations.
Partner with your care team
Share results during prenatal visits. Dietitians, MFMs, and OBs can personalize nutrition, supplements, and activity plans.
Formula
BMI = Weight (kg) ÷ [Height (m)]²
Weight gain = Current twin pregnancy weight − Pre-pregnancy weight
Apply IOM (2009) twin pregnancy gain ranges according to BMI category.
Monitor weekly gain: total gain ÷ gestational weeks since week 13 ≈ kg/week.
Full Description
Twin pregnancies demand higher caloric intake (typically +600 kcal/day by mid-pregnancy), increased micronutrients (iron, folate, calcium, DHA), and closer monitoring for anemia, preeclampsia, and fetal growth. Weight gain that aligns with BMI-based recommendations correlates with improved birth weights and lower NICU admissions.
Aim for steady gain: ~0.6–0.9 kg/week in the second trimester and ~0.5–0.8 kg/week in the third, depending on BMI. Consult your care team about individualized targets, appetite changes, physical activity, and symptom management.
Frequently Asked Questions
Do I need extra protein?
Yes. Aim for 1.4–1.6 g/kg/day or as recommended by your dietitian to support twin growth and maternal tissues.
What if I gain too quickly?
Evaluate fluid retention, gestational diabetes, and dietary balance with your provider. Adjust meal composition and activity level accordingly.
Can I exercise with twins?
Many twin pregnancies can continue moderate exercise (walking, swimming). Always follow individualized guidance from your provider.
When is weight gain most critical?
Second trimester weight gain strongly correlates with birth weight. Focus on consistent, nutrient-dense intake during weeks 14–28.