You’ve made it to week 33 pregnancy, 31 weeks from conception. You will be holding your baby before you know it! Let’s check in on how you and baby are growing, talk about symptoms you may be feeling, and learn about what it would be like if baby were to be born this week.
Week 33 Pregnancy: How Big is Baby?
Your baby continues to gain weight quickly. He’s gaining about 1/2 pound a week as he gets ready for birth. He now weighs in at around 4 1/4 pounds. He’s about 12 inches long from crown to rump, or 17 1/4 inches from crown to heel (1).
What else can we learn about your cute, tiny one?
- He closes his eyes when asleep and opens them when awake.
- He drinks up to a pint of amniotic fluid a day. This is practice for his gastrointestinal system.
- You likely have more baby than amniotic fluid now, making his movements feel stronger and sharper (2).
Week 33 Pregnancy: Baby Bump
Your bump continues to grow steadily, right along with your baby. You can now feel the top of your uterus about 5 1/4 inches above your belly button. When your doctor or midwife measures the distance from pubic symphysis to fundus, it’s now about 13 1/4 inches.
If your pre-pregnancy weight was in the range of normal, and if you’ve gained the recommended amount along the way, you’ve probably gained between 20 and 27 pounds. You’ll continue to gain a pound or two a week until baby is born.
Week 33 Pregnancy: Symptoms
Progesterone, Estrogen, Oxytocin, Relaxin
We’ve talked about hormones throughout your entire pregnancy, as they’re responsible for nearly every symptom we’ve covered. You’re currently right at the point where estrogen and progesterone are at their highest. Estrogen levels are now six times what they were before your pregnancy.
All the hormones that have worked together to change your body and support your baby will soon begin shifting to prepare for the onset of labor. Near the time labor starts, progesterone will drop, oxytocin levels will rise to produce contractions, and relaxin will also increase to loosen ligaments and help relax the cervix.
Hormone changes can make you feel like you’re on an emotional roller coaster. This is especially true when those hormones are paired with exhaustion, lack of sleep, and fears and excitement about huge life changes. Take time to rest, relax, and recharge as often as you can; this will help with the non-hormone components. As for the hormones, you’ll just have to hold on and ride it out. Be gentle with yourself. Sometimes just recognizing that there’s a reason behind your emotions makes them easier to cope with.
You probably hoped you were done with nausea when morning sickness passed, but may have discovered that you’re feeling sick again. Nausea and heartburn are not unusual, and in fact, some women even lose a few pounds right at the end of their pregnancies (4). As with almost every symptom we’ve discussed, changing hormones may play a role. The other factor is that your baby has grown so much that your stomach is running out of room.
You may find that it helps to eat multiple smaller meals throughout the day rather than three larger ones. Just be sure that you are eating regularly. Having an empty stomach can make both nausea and heartburn worse. Even more importantly, both you and baby need the energy for the stress of labor and birth.
What if Baby is Born at 33 Weeks?
If you were to deliver your baby now, you would likely be scared and worried and overwhelmed, and all of those feelings are understandable. However, the great news is that a baby born at 33 weeks gestation has a great chance of not only surviving, but doing so without long-term complications. Premature babies born at 33 weeks are considered moderately preterm. They will likely have only a short NICU (Neonatal Intensive Care Unit) stay and few complications (5).
The main concerns for a premature baby are:
- Immature lungs. Baby may need a little help with breathing at first.
- Body temperature regulation. Baby may need to spend some time in a temperature-controlled isolette until she is able to maintain her own body temperature.
- Feeding. A preterm baby sucks weakly and her swallow and gag reflexes are unreliable. Eating on her own and gaining weight is usually the last hurdle a premature baby overcomes before being discharged from the hospital.
You can find more great information about premature babies on the March of Dimes website. If you find yourself parenting a premature child, the March of Dimes may be a valuable resource for you.
(1) Glade, B.C., Schuler, J. (2011). Your Pregnancy Week by Week, 7th edition. First Da Capo Press.
(2) What to Expect. “Watch Your Baby’s Growth at Week 33.” What to Expect, 17 Jan. 2019, www.whattoexpect.com/pregnancy/week-by-week/week-33.aspx.
(3) Daley, Kate. “How Pregnancy Hormones Affect Your Body in Each Trimester.” Today’s Parent, 19 Dec. 2018, www.todaysparent.com/pregnancy/pregnancy-health/how-pregnancy-hormones-affect-your-body-in-each-trimester/.
(4) The American College of Obstetricians and Gynecologists. (2010). Your Pregnancy and Childbirth Month to Month, 5th edition.
(5) Bird, Cheryl. “The Different Stages Premature Babies Can Be Born.” Verywell Family, www.verywellfamily.com/premature-babies-week-by-week-2748606.