Welcome to the end of the first trimester! Week 13 is officially the last week of the first trimester, and your baby is really growing now. For many mums-to-be, the second trimester is the ‘happy trimester’ when they enjoy glowing skin, a noticeable increase in mood and energy (especially if you experienced fatigue early on), and even increased libido. Whilst this sounds great, and hopefully you will have an easy second trimester, remember that every woman experiences pregnancy differently and for some the tiredness and nausea continue throughout.

Your Body

Whilst your bump will still be small, if it is noticeable at all, your uterus is now above the level of your pubic bone and you may be able to feel it.

Around week 13, and continuing throughout the remainder of your pregnancy, your breasts will be preparing to feed your baby; they will start to produce colostrum. If you choose to breastfeed, this nutrient-rich fluid will be your baby’s first food. Besides being a complete source of nutrition, colostrum is also used to help your baby’s immune system develop. Some people even refer to colostrum as ‘liquid gold’, such are its beneficial properties.

With the end of the first trimester approaching, now might be a good time to consider how well you are looking after yourself. Have you been continuing with your prenatal vitamins? Exercising regularly and appropriately? If you are working, are you factoring in short breaks as required?

A quote often cited with regards to pregnancy is, “you’re eating for two now, so go ahead and eat whatever you want”. Whilst it is true that you are eating for both yourself and the baby, it might be helpful to remember that by week 13 one of you is still only the size of a tomato! Throughout pregnancy, experts generally advise women to consume an extra 300 calories a day. That’s only 300 calories! To put that into perspective, a tablespoon of butter has about 100 calories. A banana also has 100 calories. Ideally, the additional 300 calories should come from healthy sources; consider adding extra vegetables, lean proteins, and complex carbohydrates, like full grains, to your diet.

There is another good reason to be careful about your diet and weight gain. Gradual weight gain helps to minimise the extent of stretch marks. Up to 90% of women develop stretch marks, and they are thought to occur predominantly in response to increased hormone levels, specifically oestrogen and relaxin. However, rapid or excessive weight gain can make stretch marks worse. If you do develop stretch marks, the good news is that they usually fade after delivery and, over time, will become barely noticeable. Despite claims made by the beauty industry to the contrary, there is no magic cream to “cure” stretch marks, but there are things you can do, such as keeping weight gain gradual and reasonable, to lessen them.

Your Baby

Your baby’s foetal age is 11 weeks. A baby that is developing normally will now be about the size of a medium tomato or a lemon. At this stage, approximately half of the baby’s size is just their head, and they can look slightly ‘alien-like’ on scans. Don’t worry, his or her body will start to catch up over the coming weeks and within the next two months, your baby’s head will shrink from about half of the crown-to-rump length to one-third.

Around this time, one of the major changes occurring is in your baby’s digestive tract. Over the last few weeks, your baby’s intestines have been rapidly growing and even started to function (remember last week, when the small intestine could start to absorb and process sugar?) To date, the intestines have actually been growing outside of the baby’s body. During the third month of pregnancy, the intestines will begin to migrate back into the abdomen where they belong and settle into their proper place. Why do babies develop like this? Probably to give the embryonic cavity space to enlarge as the intestinal tract is such a large and complex structure; by the time your baby is born, he or she will have over 3.3 metres of intestines carefully packed into a cavity the size of a large apple.

Other interesting developmental changes are occurring by week 13. Your baby’s internal reproductive organs are now advanced. A female foetus will already have millions of eggs in her ovaries; these will last her until she reaches menopause and she will never produce more. Furthermore, even though your baby is still months away from his or her first cry, their vocal cords are starting to form.

Doctor’s Tip:
“Unfortunately, there are no good studies that prove that creams and treatment to prevent stretch marks actually work.”

Your Pregnancy, Week 12 < > Your Pregnancy, Week 14

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