Facts About You and Your Developing Baby In Each Trimester

Pregnancy can be a cause for both celebration and worry, especially with all the changes you may notice over time. Check out some interesting facts below regarding what you and your developing baby may experience during pregnancy.

How Long Can I Expect To Be Pregnant?

Most full-term pregnancies last about 40 weeks, with three trimesters lasting three months each. Of course, there’s room for variation, with some pregnancies lasting as long as 41 weeks. A trimester can also range between 12 to 14 weeks.

No surefire method determines exactly how long you can expect your pregnancy to last. Your due date will be determined by taking into consideration the first day of your last menstrual period (LMP) and the earliest sonogram you have where a fetal heartbeat can be detected. Once that due date is determined, it should never be changed.

The First Trimester: Week 1 to Week 13

Your First Trimester

During a regular cycle, an ovary releases an egg, which travels through a fallopian tube by the second week. The sperm fertilizes the egg (this is called conception) and they become a zygote during week three. A zygote is made up of fetal cells that divide and grow rapidly.

Around week six, most future parents suspect they’re pregnant and their pregnancy test will show a positive result. You may start to experience bodily discomfort due to the surge in hormones, including the following symptoms:

  • Nausea
  • Fatigue
  • Headaches
  • Constipation
  • Morning sickness

This adjustment period usually dials down around 13-14 weeks of pregnancy, so hang in there. Many people feel they need to stop drinking caffeine around this time. However, the sudden stop may lead to headaches or migraines. Tapering down your caffeine intake is okay but generally around 220 mg/day of caffeine is considered an acceptable amount during pregnancy.

Your Baby’s First Trimester

The zygote becomes a blastocyst that latches onto the protective lining inside of your uterus. As the cells continue to multiply, an amniotic sac forms around them for cushioning and protection. At the start, this little bit of living and growing cells is smaller than an inch.

By week four, the embryo has not fully formed major organs or limbs. However, by the end of week eight, the umbilical connection secures and the placenta begins to feed your baby with oxygen and other nutrients. The small cells that beat from electrical energy have already become a fully functional, beating heart by week six. Congratulations: Your baby has upgraded from an embryo to a fetus!

From week 10 and on, you may elect to do genetic testing to look for chromosome abnormalities and certain genetic carrier conditions. This is a blood test drawn from your blood and is not invasive for the baby.

The Second Trimester: Week 14 to Week 27

Your Second Trimester

While the morning sickness may fade (unless you have hyperemesis gravidarum), don’t be surprised if you experience occasional dizziness, heartburn, or an increased need to urinate. The baby’s growth will start affecting your weight, center of gravity, and, of course, your internal organs. Expect extra pressure on your stomach and bladder as the baby takes up more space.

You’ll likely start showing around this time, so count on packing away your favorite jeans for a while. Also, work on maintaining a healthy weight with a well-balanced diet, and exercise. You and your developing baby need healthy fats and other nutrients to provide enough energy for both of you.

Your Baby’s Second Trimester

Your little one has cranked their fetal development up. They will increase from the size of a plum to that of a small watermelon by the last week of this trimester. Your baby will also start looking more like a newborn, complete with opposable thumbs that they can suck!

Because they have bones and muscles, babies will start to move, turning to assume a comfortable upside-down position. By 20 weeks most mothers begin to feel their baby moving for the first time. While it does not yet feel like strong kicks, the feeling often reminds women of little flutters or gas bubbles. In addition to measuring movement at this time, your provider will order a sonogram to look at all of your baby’s anatomy.

The Third Trimester: Week 28 to Birth

Your Third Trimester

It’s the countdown you’ve been waiting for, and you can expect your final week of pregnancy around 37 to 41 weeks. Prepare for frequent medical visits. Your doctor will want to ensure you and your baby stay healthy and safe during this delicate time.

Your Baby’s Third Trimester

Your baby’s major organs, bones, and tissues should be ready for outdoor exposure by this time. You may notice their sleeping patterns, favorite hand to use, and other traits before their personality forms. They’re getting ready to meet you in just a few weeks!

Pregnancy care at Women’s Healthcare Associates

The staff at Women’s Healthcare Associates in Amarillo, TX has the tools and experience to care for you and your developing baby. We help maintain the prenatal health of our patients through detailed monitoring and healthy habit advice, among a variety of other services. Our team wants you and your developing baby to have a great start in your new life together! To learn about our prenatal care options, please call (806) 355-6330 to schedule an appointment.

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1301 S Coulter St # 300
Amarillo, TX 79106

Phone: (806) 355-6330

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