The Third Trimester: What's happening in your body?

You are in your third trimester between weeks 27 and 40+ of your pregnancy and as you progress closer to your due date, you will start to see (and feel!) lots of growth! It's very common tiredness to kick in again, possibly just like your first trimester, but what exactly is happening in your body during this time?



Approaching due date, your uterus lies just below your diaphragm, so space gets more limited leading to more shallow breathing and breathlessness. Late-pregnancy specific exercise, helps create space in your torso and alleviates the pressure of your growing baby on diaphragm and organs.


The space between your six-pack muscles (rectus abdominus) has likely widened by this point. It's important to point out here, that you may read in some sources that the abdominal muscles "separate", or "divide", or "split". This isn't accurate terminology! The tissue that lays between the rectus muscles is called the linea alba and this "separation" is merely the linea alba stretching. Interestingly, 100%, yes 100% of women have Diastasis Rectus Abdominus (DRA) by the end of their pregnancy. The degree of stretch (and how well this DRA heals) depends on many many different factors including posture, muscle balance through the rest of the body, nutrition, hydration, digestive health, how your breathe, and performing appropriate core exercises through pregnancy. As a general guide, it's important to avoid any curl-up type movements, planks or rolling back movements during this time as well as taking care doing any loaded twists or side bends. Pregnancy core exercises should integrate what I call, Core Breathing and also pelvic floor contraction as well as relaxation in preparation for the birth itself!


Due to hormonal changes, your digestion can also become more sluggish and you may experience heartburn, constipation and bloating. Staying active and again prioritising exercise to create space in your body and improve your posture and alignment is really important.


Your posture is really affected by your growing baby and heavier breasts. Your lower back will become more arched and your pelvis will tip forwards. You may start to subconsciously try to counteract this by shifting your whole pelvis forwards. Again, appropriate pregnancy exercise will help offset postural shifts during your pregnancy, which will help your baby navigate into an optimal position ready for birth.



Hormonal changes, increases in blood volume and fluid retention, weight gain, and slower digestion may mean you begin to suffer with swelling, especially in your calves and ankles. This is more common through the Summer months. It's important to start hydrated and stay active to encourage blood circulation.


If this is your first pregnancy, your baby may "engage" a few weeks before birth. This means their head will descend into the pelvis in preparation for birth. It's not uncommon for this to happen later in subsequent pregnancies, even during labour. At this point, there will be more demand on the pelvic floor and it's important that you include specific pelvic floor exercises. This doesn't mean endless clenches all day long, but an equal mix of pelvic floor contraction and relaxation built into functional movements and exercises.


What can be very hard during this trimester, is recognising the need to rest. If you're on the go a lot of the time, have a family already, have a full-time job etc., it's not a sign of weakness if you need to recognise the need to slow down, at any point during our pregnancy! Take a look at your weekly commitments. Can you identify any areas that aren't currently serving you and your pregnant body?



Many women experience pelvic pain during their pregnancy. This pain can be felt around the pubic bone across the front of the pelvis, in the back of pelvis region or lower back (maybe on one side) or even spreading down into the thighs. Pregnancy-related pelvic pain is more common in subsequent pregnancies and it is thought that this is because of the already demanding role of being a parent already. Pelvic pain can of course occur in first time pregnancies too, but generally it is very much related to psychological and emotional factors as well as posture shifts. The pain felt ISN'T indicative of damage around your pelvis. The pelvis is an incredibly stable structure in your body, but due to hormonal changes, it is totally normal for the ligaments around pelvis to become more supple, which is EXACTLY what we need for birth! This change in the body though is sometimes detected as a "danger" by our brain and pain is the result.


This pain can be incredibly debilitating and emotionally draining, plunging you into a vicious cycle. It's important to seek help with pelvic pain, reduce stress and busyness, build in self-care to your routine, and undertake an exercise regime to improve alignment and appropriately strengthen and release certain muscles around the pelvis. Ultimately, there is hope, so please don't suffer, becoming more inactive and more in pain.


Your blood pressure is also an important factor in the later stages of pregnancy. High blood pressure can be a sign of pre-eclampsia, which can become a serious complication for mother and baby. Take steps to control your blood pressure by staying active (getting slightly breathless a few times a week), controlling your weight gain by eating a diet based on vegetables, quality protein, good fats and fruit, and prioritise self-care activities such as relaxation classes, taking breaks from work, getting support, removing draining commitments (and people) from your life.


A sign of carpal tunnel syndrome (CTS) is a tingly, numb feeling in the wrists and hands. This is again, due to a build up of swelling squeezing on the median nerve in your wrist. CTS can be worse if you have weakness in your upper body or if you've gained a lot of weight, but you can receive treatment to ease the symptoms of CTS. It should go away completely after pregnancy.


It's very common for the skin on your bump to become itchy as your baby grows, but itching around your body especially on your hands and feet could be a sign of obstetric cholestasis, which is a liver condition which would require medical attention. Please ask your midwife for advice without delay.


Based on what's happening in your body, choose exercise that is not depleting your energy, but rather keeping you energised and active. Keep sessions regular but short. Move from one position to another with care and reduce the amount of time doing exercise laying on your back. Prioritise movement and exercise that is going to prepare you for late-pregnancy, labour, and birth. A programme that is conscious of pregnancy posture, the demands of labour and how to optimise baby positioning.


For more information on pregnancy exercise, birth preparation, pregnancy-related pain, please get in touch. I offer a range of services specifically for pregnant women including:

  • Birth Ready - a pelvic-health focused birth preparation course,

  • Therapeutic and Relaxation Pregnancy Massage,

  • 121 Antenatal Private Coaching, and

  • Group classes to support and active and strong pregnancy.