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The process of nurturing a life inside you and giving birth puts great demands on your body. A pregnant woman undergoes drastic hormonal and physical changes, which reach their culmination in the third trimester.
Most people associate pregnancy with a belly bump and occasional nausea, but there’s more to it than just these changes. In fact, every pregnancy is different with every woman facing her own challenges. Some have it easier than others.
The third trimester refers to the last 3 months of pregnancy, which is a challenging but exciting time for the childbearing mother. It encompasses the final changes for both mother and child before birth.
Duration of the Third Trimester
As defined by the American College of Obstetricians and Gynecologists, the third trimester begins at week 28th and lasts until the birth of the fetus. (1)
What Changes Happen to the Fetus During the Third Trimester?
During these last weeks, the fetus is already formed, and the majority of changes happen in size rather than development. It is a phase of growth, where all organs go through volume changes and become adaptable to extrauterine life.
The brain and lungs finish their physiologic changes last, which is why a preterm birth might compromise the functionality of any of these organs.
There is an average of 30gr/day of fetal weight gain, and it ends with the body composition the baby will have at birth. Genetics and environmental aspects might play an important role in the growth rate.
Common Discomforts During the Third Trimester of Pregnancy
Each pregnancy is different. It’s safe to say the majority of, if not all, moms feel complex and bothering adjustments during the last weeks, even months, of the gestation.
A bigger baby, more amniotic fluid, higher fluid retention (what doctors call third spacing), weight gain on mom, and physiologic changes in different organs including the uterus, breasts, skin, and vascular system – they all contribute to a heavier body and a shift in the center of gravity.
Also, the mother is getting ready for birth and nursing, which alters the way organs function, temporally.
The most common complaints include frequent urination, repeated falls, fatigue, tiredness, insomnia (most of the time due to increased fetal movement, anxiety, unexplained), heartburn, skin tone changes and discoloration, vaginal discharge, abdominal pain and sensation of stretching, and genital and breast engorgement.
Insomnia During the Third Trimester
Unfortunately, insomnia is quite common during pregnancy, especially at the end of the third trimester. (2)
Several factors are to blame for this: increased fetal movement, a heavier body, justified anxiety due to several upcoming changes, and discomfort with a bigger/fuller belly. Sometimes, it might be inexplicable.
Important attention is given to diabetic moms and certain populations who need to get up in the middle of the night for snacks (to prevent low sugar levels) or medications at odd hours. Reconciling sleep after these breaks might be challenging as well.
Do All Pregnant Women Suffer From Braxton Hicks Contractions?
Yes! Whether they feel it or not.
Braxton Hicks contractions are benign, innocuous movements of the uterus, more specifically of the smooth muscle layer called the myometrium, which lacks the ability to take the mother to the following step: real labor.
It’s a way for the reproductive system to practice for birth, and as long as no progress on cervical dilation is made, they represent no danger. Some factors, such as dehydration and strenuous exercise, might trigger more frequent and painful contractions.
Safe Ways to Relieve Pregnancy-Related Back Pain
Back pain during the third trimester is common due to a shift in the center of gravity. (3) Factors contributing to pain include excessive weight gain, comorbidities, multiple gestations, false labor, and previous skeletal conditions.
Training the back for these new changes and abrupt responsibilities can be accomplished through different methods. One of them is relaxation and breathing techniques.
Many mothers use yoga and swimming as a workout because it’s friendly and safe for both the mother and baby while improving elasticity and cardiovascular conditions.
Ice packs, special pillows, topical pain-relief lotions, bedtime devices, and improving postural hygiene have been all proven to help control pain. (4)(5)(6) It is very important to avoid anti-inflammatory and other medications that might compromise fetal well-being. For treatment and a more invasive approach, speak with your provider.
Fatigue and Shortness of Breath During the Final Trimester of Pregnancy
Remember, there is an increase in the weight of both mom and fetus as well as fluid retention during the third trimester.
While the demand for keeping up with a whole new body is constantly challenged, it is at the end of the day, the same heart, lungs, and muscles that take all the extra work. There is also an increase in abdominal content, which might translate into less space for the diaphragm (major respiratory muscle) to expand.
Factors such as polyhydramnios (an excessive amount of amniotic fluid), (7) macrosomia (bigger fetus than expected for gestational age), (8) cardiac or respiratory preconditions, maternal obesity, and many others might worsen the problem with breathing.
Heartburn in Pregnant Women
Heartburn or acid reflux happens when the acidic content of the stomach backs up to the esophagus. Some symptoms might include a burning sensation in the throat or chest, abdominal pain, nausea or/and vomiting, and distension. (9)
Changes in some hormone levels during pregnancy, specifically progesterone, cause disruption in the normal motility of the gastrointestinal tract and relaxation of the esophageal sphincter, resulting in heartburn.
It might be a good idea to avoid triggers such as tea, coffee, citrus, and fatty foods, as well as leaning back or going to bed within 3 hours of eating.
Early Symptoms of Labor to Watch Out For
Let’s start revising the definition of labor first. A modern yet clinically relevant explanation of the concept would be regular and effective uterine contractions strong enough to cause progressive dilation of the cervix, accompanied by descent and eventual expulsion of the fetus. (10)
Unfortunately, labor is a clinical diagnosis, which means it has to be identified through a physical exam by a trained provider; no tests are available.
Some signs to be on the lookout for include crampy abdominal pain, on and off, or intermittent in nature, which doesn’t go away after some time (an hour or so) or with changing positions. Excessive leakage of fluid and decreased or exaggerated fetal movements might also help with the diagnosis.
Lifestyle Changes to Ease Your Discomfort During the Third Trimester
The following measures can help ease the last phase of your pregnancy without causing any undue complications:
- Frequent exercise, comfortable enough to have a conversation without shortness of breath
- Light and small portions of food every 3–5 hours if possible
- Wearing comfortable shoes
- Practicing breathing and relaxation techniques as early in pregnancy as possible
- Strict weight gain to avoid unnecessary increases, which might be extra challenging postpartum
Keep Your Ob-Gyn in the Loop
It is crucial to have an effective, open, and bidirectional communication with your doctor. It is very important to be receptive to suggestions and directions during the whole process.
There should be no fear of embarrassment or intrusion when it comes to talking to your obstetrician about ideas and plans of action or bothersome symptoms.
Most, if not all, providers have several options to keep an open and honest conversation with their patients. Portals and office coordinators, whose job is to make that communication effective and fluent, are also a useful tool.
The final goal should be to bring the baby and mom to a happy, healthy ending of pregnancy.
Childbearing women are at their heaviest during the third trimester when the fetus becomes a fully developed baby.
As the delivery date nears, it might be a good idea for you and your partner to enroll for coaching, such as provided by Lamaze classes. This coaching will offer the right tools to prepare you for childbirth. This is particularly true for first-time parents.
The final few months can be quite discomforting, but seek comfort in the fact that it will all be over soon, and you will have a beautiful, healthy baby by the end of it.