36 weeks pregnant baby weight in grams

During pregnancy, you’ll see your bump get bigger as your baby develops inside your uterus (womb). By 40 weeks, the average baby weighs 3.5kg (7.6lb), and is about 51.2cm long from head to heel (Hill 2019).

Table of Contents Show

What is the normal baby weight at 36 weeks?
How much should a 37 week fetus weigh?
What is the normal weight of baby at 37 weeks in kg?
What is the best fetal weight?

But how big is your baby right now? We’ve put together this simple chart to tell you the length and weight of an average baby from eight weeks of pregnancy, through to birth.

Bear in mind that boys tend to be longer and heavier than girls (Cole et al 2011, Villar et al 2014, 2016), and that every baby is different. So don't worry if the measurements in your maternity notes are different from those listed below. Your baby’s growth will be checked during your pregnancy, including through these ultrasound scans:

During your dating scan or nuchal translucency (NT) scan between 10 and 14 weeks. Your sonographer will measure your baby from her head to her bottom. This is called the crown-rump length (CRL), and it will be used to work out your due date (Mizia et al 2018, NCCWCH 2008, NHS 2018).
At your anomaly scan, which you’ll have at around 20 weeks. Your baby will be more active, meaning CRL isn’t as accurate. Instead, your sonographer will check your baby’s head circumference (HC), abdominal circumference (AC) and thigh bone (femur) length (FL) (ASUM 2018, NHS 2018).

To keep things simple, our chart uses crown-rump length measurements from eight weeks to 19 weeks, then crown-to-heel measurements until 42 weeks.

Pregnancy week	Length (centimetres)	Mass (grams)
8 weeks	1.6cm	1g
9 weeks	2.3cm	2g
10 weeks	3.1cm	4g
11 weeks	4.1cm	7g
12 weeks	5.4cm	14g
13 weeks	7.4cm	23g
14 weeks	8.7cm	43g
15 weeks	10.1cm	70g
16 weeks	11.6cm	100g
17 weeks	13.0cm	140g
18 weeks	14.2cm	190g
19 weeks	15.3cm	240g

(Hill 2019)

The lengths below are from crown to heel:

Pregnancy week	Length (centimetres)	Mass (grams/kilograms)
20 weeks	25.6cm	300g
21 weeks	26.7cm	360g
22 weeks	27.8cm	430g
23 weeks	28.9cm	500g
24 weeks	30cm	600g
25 weeks	34.6cm	660g
26 weeks	35.6cm	760g
27 weeks	36.6cm	875g
28 weeks	37.6cm	1kg
29 weeks	38.6cm	1.2kg
30 weeks	39.9cm	1.3kg
31 weeks	41.1cm	1.5kg
32 weeks	42.4cm	1.7kg
33 weeks	43.7cm	1.9kg
34 weeks	45.0cm	2.1kg
35 weeks	46.2cm	2.4kg
36 weeks	47.4cm	2.6kg
37 weeks	48.6cm	2.9kg
38 weeks	49.8cm	3.1kg
39 weeks	50.7cm	3.3kg
40 weeks	51.2cm	3.5kg
41 weeks	51.5cm	3.6kg
42 weeks	51.7cm	3.7kg

(Hill 2019)

More on your growing baby:

See how big your baby is now in our fruit and veg comparison slideshow.
Check out our week-by-week guide to fetal development.
Learn what it may mean if your baby is smaller or larger than average.

References

ASUM. 2018. Guidelines for the performance of second (mid) trimester ultrasound. Australasian Society for Ultrasound in Pregnancy. www.asum.com.au [Accessed October 2019]

Cole TJ, Williams AF, Wright CM, et al. 2011. Revised birth centiles for weight, length and head circumference in the UK-WHO growth charts. Ann Hum Biol 38(1):7-11

Hill MA. 2019. Fetal development: length – weight table. University of New South Wales, Embryology. embryology.med.unsw.edu.au [Accessed October 2019]

Mizia K, Campbell Westerway S, Robertson M. 2018. Guidelines for the performance of first trimester ultrasound. Australasian J Ultrasound Med 21:179-82

NCCWCH. 2008. Antenatal care: routine care for the healthy pregnant woman. Updated February 2019. National Collaborating Centre for Women’s and Children’s Health, NICE clinical guideline, 62. London: RCOG Press. www.nice.org.uk [Accessed December 2018]

NHS. 2018. NHS Fetal Anomaly Screening Programme handbook. NHS, Fetal Anomaly Screening Programme. www.gov.uk [Accessed October 2019]

Villar J, Cheikh Ismail L, Victora CG, et al. 2014. International standards for newborn weight, length and head circumference by gestational age and sex: the newborn cross-sectional study of the INTERGROWTH-21st project. Lancet 384(9946):857-68

Villar J, Giuliani F, Fenton TR, et al. 2016. INTERGROWTH-21st very preterm size at birth reference charts. Lancet 387(10021):844-5

Megan Rive is a communication, content strategy and project delivery specialist. She was Babycenter editor for six years.

What is the normal baby weight at 36 weeks?

Week 36. Baby: Your baby measures about 20.7 inches from head to toe and weighs about 6 pounds.

How much should a 37 week fetus weigh?

Your baby at week 37 of pregnancy The average length of a baby at 37 weeks gestation is 19.1 inches (48.5 cm). Baby likely weighs 6.3 pounds (2.8 kg) and is packing on half an ounce (14 g) per day.

What is the normal weight of baby at 37 weeks in kg?

More than 9 out of 10 babies born at term (37 to 40 weeks) weigh between 2.5kg and 4.5kg. If your baby weighs 4.5kg or more at birth, they are considered larger than normal. This is also known as 'fetal macrosomia' and large for gestational age (LGA).

What is the best fetal weight?

Thus, depending on many factors, the optimal birth-weight range to minimize the risk of fetal and maternal morbidity and mortality is between 3000-4000 g.