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Your Healthiest Pregnancy: Trimester by Trimester

By Susan Peck, MSN, APN

Your Healthiest Pregnancy: Trimester by Trimester

Experts agree that the best way to have the pregnancy and birth that you envision is to begin with a qualified healthcare provider who shares your beliefs and values about pregnancy, labor and birth.

Your 1st Trimester: Weeks 1-12

From pregnancy tests to morning sickness, here’s how it all begins

Welcome to your 1st and sleepiest trimester; during these 12 weeks your baby will grow from an embryo 1/5th the size of the period at the end of this sentence to a nice juicy plum. Every day, the pregnancy hormone HCG is increasing and it’s what makes your pregnancy test positive. It’s also responsible for feeling tired, tender or sore breasts, frequently needing to pee and for many women—morning sickness. It’s normal to want a nap every day—your body is working hard to grow your baby—it’s exhausting!

Start—or continue—habits that keep your pregnancy as healthy as possible all the way to term:

  • Daily prenatal vitamin, especially if you haven’t been taking one
  • Make and keep all prenatal appointments
  • Healthy food with lots of water
  • No, smoking, drinking or using illegal drugs if you have any of these habits
  • Caffeine limited to no more than 200mg a day—that’s up to 12 ounces of coffee. Foods like chocolate and other beverages have caffeine too

Before you knew you were pregnant, baby’s neural tube—what becomes her brain and spinal cord—formed and closed. The 800 micrograms of folic acid in most prenatal vitamins protect against neural tube birth defects, so it’s important to take a prenatal vitamin before conception and through pregnancy and breastfeeding.

Baby finishes the 1st trimester 10 times bigger than at conception. Your body is changing too: Your breasts are likely bigger and sore, you may have frequent headaches, fatigue and nausea. It’s not unusual to have some spotting or mild cramping and this doesn’t always mean miscarriage. Call your provider right away, especially if the bleeding is heavy or if you’re cramping.

Around week 8, you’ll have your first prenatal visit; after that you’ll likely see your provider:

  • Every 4 weeks (until 28 weeks)
  • Every 2 weeks (28-36 weeks)
  • Weekly (week 36+)

You may be offered 1st trimester screening—non-invasive tests done between weeks 11-14 for chromosome disorders like Down Syndrome and genetic testing. Your nurse can talk with you about the risks and benefits of these tests. Bring your questions to every prenatal visit—your care providers expect and welcome them!

As you complete week 12, you can relax—all of baby’s organs and bodily systems have formed and the next 28 weeks are all about growing. You’ll be able to hear your baby’s heartbeat and the early symptoms of pregnancy should begin to subside.

Your Pregnancy By Trimester

Pregnancy is 40 completed gestational weeks, the count for which starts on the first day of your last menstrual period. Those 40 weeks are divided into 3 trimesters:

  • 1st trimester: Weeks 1-12
  • 2nd trimester: Weeks 13-27
  • 3rd trimester: Weeks 28-40

Choose a Pregnancy-Friendly Provider

For pregnancy care, your provider may be a midwife, obstetrician or family practice doctor. Then evaluate the facility where she or he will help you birth.

Use our checklist to gauge how your potential birth facility may match your goals for labor and birth. This list is doesn’t cover everything but for each ‘yes’ you can give, the greater the chances that you may be supported toward your desired birth.

Ask if the facility where your provider will help you give birth is committed to:

  • Supporting natural birth with freedom to move around, and equipment, such as birthing beds to support upright labor and birth, birthing balls and showers or tubs for pain relief and labor support, limited use of electronic monitoring unless medically indicated and staff to provide ongoing labor care
  • Induction or cesarean only when medically needed: You’re more likely to have cesarean surgery if the facility has cesarean rates above the national average (now 33%); risks to mom and baby increase when major surgery could have been prevented
  • Rooming in: This keeps your baby with you 24/7, increasing your opportunities for breastfeeding and bonding
  • Breastfeeding as the optimal food and best way for you to feed your baby, including having expert lactation support available
  • Initiating breastfeeding as quickly as possible post-birth: Ideally, within the first minutes of life but no longer than an hour for a normal, vaginal birth; and within 2 hours if you undergo cesarean
  • Skin-to-skin care: This helps baby more rapidly stabilize his or her heart rate, temperature, and respiratory rate, improve bonding and increase breastfeeding success
  • Baby-Friendly™—this designation goes to hospitals and birthing centers that give moms the information, confidence and skills needed to successfully start and continue breastfeeding their babies, as well as feeding formula safely for those moms who will do so. It’s part of the global Baby-Friendly Hospital Initiative by the World Health Organization and the United Nations Children’s Fund. Find a Baby Friendly™ facility near you: org/eng.

How much weight should I gain in pregnancy?

It’s important to gain just the right amount of weight in pregnancy: Not too little, not too much.  Follow these simple strategies to nourish you and baby together:

  • Know that no one food combats morning sickness; smaller meals eaten more frequently seem to help
  • Eat 3 servings of protein daily, such as lean meats, low-mercury fish, nuts, beans, milk or eggs, to support your growing baby
  • Eat no more than an extra 100 calories a day—that’s a small apple and 6 ounces of skim milk
  • Bulk up on fruits, veggies and water to combat constipation
Pre-pregnancy BMIBMITotal WeightGain Range (lbs)
Normal weight18.5-24.925-35

Plan to Carry Baby Full Term

Commit to go the full 40 weeks of pregnancy, wait for spontaneous labor and breastfeed your baby. Discover 40 reasons to go full term at GoTheFull40.com.

Pregnancy Around the World

Some pregnant Hispanic women don’t eat ‘hot’ foods such as chilies or strong spices because it’s believed these foods can cause baby to have spots or rashes.

In many countries, such as England and Australia, pregnant women get care from midwives. Physicians care for women with high-risk pregnancies, complications or those needing cesarean surgery.

In Panama, moms-to-be won’t share how far along they are; they believe sharing this will put their baby at risk for complications.

In Germany, pregnant women carry a Mutterpass—mother’s pass—at all times. It tracks their pregnancy information, vitals and tests and they bring their pass to the hospital when labor begins.

Your 2nd Trimester: Weeks 13-27

Welcome to middle pregnancy—soon you’ll be half way to term! During this trimester, your little one grows from the size of a peach to an eggplant. You’ll have more energy, feel less sick and be hungry! At 13 weeks, your placenta starts producing the hormones that maintain your pregnancy, and it gives baby oxygen and nutrition and removes waste.

You begin to ‘show’, happily trading jeans for maternity yoga pants! Other changes can include:

  • An energy burst—ask your nurse what exercises you can continue or begin in pregnancy
  • Lower back pain as your uterus grows and changes your center of gravity
  • Soreness or twinges along the sides of your belly as your uterus, stretches and moves higher in your abdomen
  • Nasal stuffiness or even snoring from increased hormones and blood flow; soothe with saline nose drops and a humidifier
  • Varicose veins in your legs—even your vagina, from relaxed blood vessels and slower circulation; elevate your legs or wear support or compression stockings
  • Itchy skin or stretch marks; belly butters and balms can ease the itching

Changes in Your Body with Baby

Around weeks 17-20 you may be surprised by flutters in your belly—that’s your baby moving! More exciting is your 2nd trimester ultrasound. Will you try to learn whether you’re having a girl or boy?

Between weeks 24-28, you’ll be checked for the most common pregnancy complication: gestational diabetes. As many as 1 in 10 women develop diabetes in pregnancy. You’ll drink a sweet liquid and have your blood drawn at 1 hour. If your 1-hour test is high, you’ll do a similar 3-hour test, but only 1 in 3 women who need that test will have gestational diabetes.

Around 27 weeks, ask for the Tdap vaccine, which protects against pertussis (whooping cough). Newborns don’t develop immunity against pertussis until they’re 2-3 months old and pertussis can be deadly in infants. Also, get a flu shot in pregnancy before flu season—this vaccine is safe in any trimester.

Your baby’s heart is beating fast—about 140-150 beats/minute, which is normal. She’s sucking and swallowing amniotic fluid as she prepares for nursing. Don’t be surprised when you feel her hiccups! Her lungs are exhaling amniotic fluid, preparing for those first breaths after birth. Your baby can recognize your voices and will respond to them at birth.

 Nutrition Know-How

  • Hydration is key; drink at least 8, 8-ounce glasses of water a day plus more during exercise
  • Minimize heartburn by skipping spicy or heavy meals, acidic fruits like tomatoes or eating late at night
  • Take in an extra 250 calories a day—up to 350 calories in the 3rd trimester—to maintain steady weight gain
  • Pick high-protein snacks like eggs, nuts, cheese sticks or hummus
  • Fill up on fiber in beans, bran or berries to keep your bowels regular

Your 3rd Trimester: Weeks 28-40

Finish this pregnancy marathon strong by letting baby pick her birthday!

In these last weeks, your baby is growing more each day as she prepares to meet you—which means as she grows you also grow more uncomfortable. Your baby is blossoming from the size of a butternut squash to a large watermelon at birth. Her weight will more than double during this trimester as she puts on more fat to help keep her warm at birth. Her brain, lungs and other organs are rapidly developing—did you know your baby’s brain is only 2/3rds of the size at 35 weeks that it will be at term?

If you’re not yet registered at your birthplace and enrolled in childbirth and breastfeeding classes, it’s time to do so. To finish strong:

  • Wait for labor to start on its own—avoid interventions in pregnancy unless medically needed
  • Alert your provider if you have any of the signs of dangerous high blood pressure in pregnancy: swelling (especially your face and hands), persistent headache, nausea or vomiting, sudden vision changes with light flashes
  • Know the signs of preterm labor—Call your provider if you have contractions closer than every 10 minutes, low back pain that won’t ease, menstrual-like cramps, fluid leaking from your vagina, increased pelvic pressure, discharge or bleeding
  • Ask your pregnancy care provider when you should call if you suspect you’re in labor

It’s normal to wonder if labor is starting with every twinge and cramp. Your vaginal discharge may increase, and your mucus plug may come out. It may look like a big, sticky piece of mucus or just heavier discharge, and it may be tinged with brown, pink or red streaks. This is all normal; call if you see heavy vaginal bleeding.

When you do go to the hospital in labor, your nurse will be with you during your labor and birth as your advocate, expert care provider and biggest supporter. Your nurse will alert your midwife or doctor to any urgent concerns that may arise.

Less than 5% of babies are born on their estimated due date—most are born between 40 and 41 weeks when labor starts on its own. Now is the time to remember your commitment to going full term and doing what’s healthy best for you and your baby—birthing normally following spontaneous labor when all is healthy and well.

What happens if I go past my due date?

You’ll have more frequent visits with your pregnancy care provider, probably twice a week, to ensure you and baby are safe and healthy. You might have a:

  • Non-stress test with a fetal monitor to check baby’s heart beat and for contractions
  • Biophysical profile via ultrasound to check baby’s muscle tone, movement, breathing, and amniotic fluid

If either of these tests is abnormal, an induction of labor may be considered.

 Susan Peck, MSN, APN, is a nurse practitioner in New Brunswick, NJ.

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