Welcome to week 20. You are halfway there!

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This week your baby’s growth rate accelerates. Your little mango is growing to about the size of a sweet potato this week. Your baby is 10.1 inches (25.7 cm) long and weighs 11.7 ounces (331 grams).

Your baby is swallowing more, which is good practice for their digestive system. They are also producing meconium, a black, sticky by-product of digestion. This sticky substance will accumulate in their bowels, and you’ll see it in the first of many diapers.

Beginning around week 20, antibodies pass through the placenta to help protect your baby in utero. The antibodies will help protect your baby during the first few months of life and build its immune system. This is an excellent time to check on how you are supporting your immune system and explore some ways you can boost your immunity.


This is the end of the first half of your pregnancy. Your uterus will start to elongate, and the walls will thin to allow more room for your baby as its growth rate accelerates this week. Your uterus is about at your belly button and grows a centimeter weekly. After 20 weeks, your care provider will measure the fundal height from the top of your uterus to your pubic bone. The number of centimeters usually corresponds to which week you are in your pregnancy. If the measurement of your fundus is off, your care provider may suggest an ultrasound to measure your baby. Measuring a week off is common, so don’t stress if the measurement doesn’t align precisely.

As your pregnancy progresses and your baby gets bigger, their movements will get stronger. The movements change from flutters early on to kicks to squirms as your baby puts on weight and gets bigger and has less room to move around in your belly. You can feel and even see them kicking your stomach from the outside, which can be pretty exciting. Tell your partner when your baby is moving so they can feel it too.

The FDA recommends that pregnant mothers avoid ibuprofen after 20 weeks because it can result in low amniotic fluid. There is also evidence that ibuprofen and NSAIDs can increase your risk for miscarriage early in your pregnancy. Always run any medication, even if it is available over-the-counter, by your doctor or midwife.

Tip for Dads and Partners

Whether you and your significant other want to know about ultrasounds or what kind of diapers to buy, there is no shortage of research to do. Ask mom how you can help split up some research and reading. Also, check the Pregnancy Podcast website. Chances are, I have already done the research for you, and you can get everything you need to know on a particular topic in just minutes.

Want more evidence-based information to navigate your pregnancy and birth?

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