It's completely natural to be curious (and perhaps a little worried) about whether your baby is growing as they should. The fetal weight doesn't increase steadily week by week but follows typical patterns throughout pregnancy, and knowing the general range of what's usually normal can be helpful.

In practice, there's rarely talk of one "correct" weekly weight gain, because growth accelerates, especially in the 2nd and 3rd trimesters, and because children are different. As a rule of thumb, the fetus typically gains the most weight in the last months of pregnancy.

Below is a cautious overview with round numbers that can be used as a guide. The weight is an average and will vary from child to child, and from pregnancy to pregnancy.

• Week 12: around 10-20 g
• Week 16: around 80-120 g
• Week 20: around 300-400 g
• Week 24: around 600-800 g
• Week 28: around 1,000-1,200 g
• Week 32: around 1,700-2,000 g
• Week 36: around 2,400-2,800 g
• Week 40: often around 3,200-3,600 g

The sources behind such benchmarks are typically obstetric reference works and Danish overviews of fetal weight (e.g., Lex.dk and week-by-week overviews like those from Babyinstituttet).

If you're looking for "weekly weight gain," the 3rd trimester is where it makes the most sense to think in grams per week. Many fetuses will gain more noticeably here, but growth can still fluctuate from week to week.

During check-ups and scans, the focus is often more on the development over time (trend) than on a single week. A single measurement is rarely enough to conclude if everything is okay.

Fetal weight is an estimate. During ultrasound, an expected weight is calculated based on measurements of, for example, the head, abdomen, and femur. This is clinically useful, but not an exact figure.

• To monitor if the baby is generally growing at an appropriate rate
• To assess the need for extra check-ups if there is suspicion of too little or too much growth
• To plan follow-up if there are other risk factors in the pregnancy

Talk to your midwife or doctor if an estimate makes you uneasy – they can often explain the uncertainty and put the number into context.

Many factors can play a role without meaning that anything is wrong. Healthcare professionals typically look at the overall picture rather than a single factor.

• Parents' height and build
• Placental function (the "working capacity" of the placenta)
• Whether it's the first pregnancy or not
• Medical conditions in the pregnant person that your doctor/midwife is already monitoring
• Length of pregnancy (birth before/after due date)

If you're told the baby is "small" or "large," it doesn't automatically mean illness – but it might mean that growth will be monitored more closely.

The most actionable thing you can keep an eye on in everyday life is not grams, but how you feel and how the baby moves.

Always contact your maternity ward, doctor, or midwife if you are in doubt. That is exactly what they are there for.

1. Note which week of pregnancy you are in and what specifically you are reacting to (movements, pain, bleeding).
2. Better to call one time too many than one time too few.
3. Ask about the plan: Should there be follow-up with an extra check-up, a new scan, or the next regular visit?

As your belly gets heavier, support for your lower back and pelvis can make everyday life more manageable. A support belt can provide relief, without directly being about the baby's weight: Support belts. If you want a specific choice, the Maternity Support Belt is a popular suggestion for extra stability as your body changes.