Month 3 (weeks 9-13)

month 3

You’ll notice visible changes in your body this month, because your baby is reaching some significant developmental milestones. Your uterus, which is usually the size of your fist, will have grown to about the size of a grapefruit in order to accommodate your rapidly growing baby – who is now 10,000 times bigger than it was at conception. Your baby’s body is recognisably human in shape, with a large head, torso, arms, and legs (and even fingers and toes). Its face is more defined, with eyes, eyelids, mouth, and nose. Its genitals have begun to form, although they aren’t developed enough to be able to see the gender. The placenta, which is your baby’s in-utero life-support system, is working to make nutrients for your baby and get rid of his or her waste products. Your baby is moving around a lot inside of you, although he or she is too small for you to be able to feel the movements just yet.

How big is my baby?

Now that your baby’s basic physiology has formed, weight gain is the primary focus. During the third month of pregnancy, your baby will rapidly put on body weight and will more than quadruple in size yet again, growing from the size of a grape to the size of a peach. At the beginning of your third month of pregnancy, your baby will be about 2cm long, and by the end of the third month of pregnancy – around week 13 – your baby will be 8.5cm long.

“Morning” sickness

By now you’re likely to be experiencing “morning” sickness, which can strike at any time, not just the morning. At the beginning of the second trimester (around week 14 of pregnancy, so after this month is over), this will start to let up. Ginger, sour lollies, and dry crackers are common nausea busters, but if you’re finding that you feel sick all the time and you can’t cope, or you’re not able to keep food and water down at all, make sure to contact your LMC straightaway as you may have a more serious condition called hyperemesis gravidarum, which can lead to weight loss, malnutrition, and dehydration.

First trimester combined screening

For many pregnant women, the first time they’ll “see” their baby is at their first ultrasound, commonly called a “scan”, at around week 12 of pregnancy. This is part of the first trimester combined screening, which includes a blood test and a scan. Results from these are combined with other information like your age, weight and baby’s gestational age (how many weeks pregnant you are) to find a screening result which can show whether there is a low or increased chance you might be carrying a baby with Down syndrome and other conditions. The blood test is best taken at 10 weeks, but can be taken between nine weeks and 13 weeks and six days. The ultrasound scan is best taken at around 12 weeks, but can be taken between 11 weeks and two days, and 13 weeks and six days. If your result shows that there is an increased chance that your baby has a condition, you will be offered further testing to see if baby actually has that condition or not. Your LMC will talk to you about first trimester combined screening and any results which need further discussion. For more info, visit


WEEK 9: Your baby is the size of a grape (2cm, 2g) and has eyelids and earlobes.

WEEK 10: Your baby is the size of an olive (3cm, 4g) and has vital organs (liver, kidneys, intestines, brain, lungs).

WEEK 11: Your baby is the size of a feijoa (4cm, 7g) and has tooth buds, fingers, and toes.

WEEK 12: Your baby is the size of a lime (5.5cm, 14g) and is developing reflexes like grasping and sucking.

WEEK 13: Your baby is the size of a peach (8.5cm, 23g), has fingerprints and can get hiccups.

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BUMP & baby is New Zealand’s only magazine for pregnancy and early babyhood. Our team of mums and mums-to-be understand what it’s like to be pregnant in this connected age, and that’s why BUMP & Baby online is geared toward what pregnant women and new mums really want to know.

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