- Pregnancy Week by Weeks
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The third trimester starts this week.
You have been building toward this for 28 weeks. The first trimester with its private nausea and exhaustion and the held breath of the early weeks. The second trimester with its returning energy, its visible bump, its anatomy scan and first unmistakable kicks and the gradual settling into the reality of the pregnancy. All of it has been preparation for this: the final stretch, the last trimester, the eleven weeks or so that stand between you and the birth.
The third trimester is a different experience from what came before it. More physically demanding. More emotionally complex. Closer to the birth in ways that make the practical preparation that felt optional in the second trimester feel urgent now. The countdown that existed abstractly in your head for the past several months becomes something with a specific and finite number of weeks remaining, and that changes how the pregnancy feels from the inside.
It also brings something that the second trimester did not: a daily awareness of your baby’s movements as a measure of her wellbeing. From week 28, and carrying forward into every week of the third trimester, your attentiveness to baby’s movement pattern is one of the most important things you can offer to your baby between appointments. More on this below.
But first, here is what is happening this week.
Your baby at 29 weeks
Your baby measures approximately 39.2cm from crown to heel and weighs around 1.37 kilograms this week. The weight gain that will characterise the third trimester is well underway, and from this point until birth your baby will gain approximately 200 grams per week on average, though the pace varies between weeks and between individual babies.
The brain is developing rapidly in ways that are directly visible at this stage of development. The characteristic wrinkled and folded appearance of the brain surface, the gyri and sulci that dramatically increase the neural surface area available for complex processing, is becoming more pronounced each week. The neural connections that will support everything your baby will ever think, feel, and do are being laid down with extraordinary efficiency.
The muscles and lungs are both continuing their progressive maturation. The muscle tone that will allow your baby to move with coordination in the months after birth is developing. The lungs are producing more surfactant with each passing week. A baby born at 29 weeks still requires intensive neonatal support, but outcomes at this gestational age are significantly better than at 24 or 26 weeks, and each additional week adds something measurable.
Your baby is accumulating fat at an increasing rate, filling in the skin that has been loose and translucent in the earlier weeks of the second trimester. The rounded appearance of a newborn is being built week by week through this third trimester fat accumulation. This fat is not cosmetic. It is the insulation your baby will need to regulate their own temperature outside the womb, the caloric reserve that will sustain baby through the first days, and the support for blood glucose stability in the newborn period.
The bones are continuing to harden progressively through the final trimester. Calcium from your diet is the building material. The skeleton that is forming now will carry your baby through their entire life.
At 29 weeks your baby can distinguish their mother’s voice from other voices. The sounds of your household, the cadence of your speech, the music you play, the rhythms of your daily life are as familiar to them as anything they have ever known. Baby will recognise them at birth.
Movement monitoring in the third trimester
From week 28, formal movement monitoring is part of how you care for your baby between antenatal appointments. The third trimester beginning this week means this is now an active part of your daily awareness rather than something approaching on the horizon.
The guidance that most gynaecologists follow is not a rigid kick count, not ten movements in two hours or any other specific number, but familiarity with your individual baby’s established normal and prompt action when that normal changes significantly.
By 29 weeks you know your baby’s movement patterns. You know the times of day they are typically most active. You know the types of movement they tend to make, the rolling and the sudden sharp kick and the rhythmic hiccup that repeats for several minutes. You know roughly how much movement to expect across a day. This knowledge, built across the second trimester, is now the baseline against which you monitor.
What to watch for: a significant, sustained reduction from what has been your baby’s normal pattern. Not a quieter hour, not a slightly different afternoon, but a change across the day that feels meaningfully different from ordinary variation.
What to do if you notice this: eat or drink something cold and sweet, lie on your left side, and pay close attention for the next hour. If your baby’s movements do not return to what feels normal for them, contact your gynaecologist the same day. Not tomorrow. Not in the morning if it is currently evening. The same day.
Your instinct about your own baby’s movements is a valid clinical signal. A gynaecologist would always rather hear from you when movement felt reduced and turns out to be fine than not hear from you when it mattered.
Your body at 29 weeks
The physical experience of the third trimester announces itself clearly at 29 weeks. The uterus now sits well above the navel and its effect on the surrounding organs and on your posture, breathing, and digestion is more pronounced than it has been at any point before.
Heartburn and indigestion are likely to be significant features of the third trimester from this point forward. The stomach is being compressed upward by the uterus while progesterone continues its relaxing effect on the oesophageal valve, producing acid reflux that is often worse in the evenings and when lying down. Smaller meals more frequently, eating slowly, remaining upright for at least an hour after eating, and raising the head of the bed for night-time heartburn are the most consistently effective approaches. Ask your gynaecologist which antacid formulations are safe if dietary adjustments alone are not providing adequate relief.
Shortness of breath during physical activity will likely worsen through the third trimester as the baby grows larger and the diaphragm has progressively less room to descend fully with each breath. This eases when the baby drops into the pelvis in the final weeks, releasing the pressure. Until then, slowing down when breathlessness arrives, choosing low-impact activity such as walking and swimming, and not pushing through significant breathlessness are the appropriate adaptations.
Back and pelvic pain is typically at its most significant from this point onward. The increasing weight of the baby, the progressive loosening of the pelvic ligaments by relaxin, and the shift in your centre of gravity forward as the bump grows all contribute to sustained musculoskeletal demand. Swimming continues to be one of the most effective forms of pain management because the water supports the weight of the bump entirely and allows full body movement without gravitational load on painful joints. A referral to a women’s health physiotherapist is worth requesting from your gynaecologist if pain is significantly affecting your daily functioning and sleep.
Braxton Hicks contractions are likely more frequent and more noticeable at 29 weeks than they have been in previous weeks. These practice contractions, a tightening across the front of the abdomen that typically lasts 30 to 60 seconds and then releases, are irregular, typically painless, do not intensify progressively, and ease with hydration and a change of position. Regular, intensifying, or painful contractions at 29 weeks warrant a same-day call to your gynaecologist rather than being attributed to Braxton Hicks without confirmation.
Swelling of the feet and ankles continues and may be worsening, particularly in the Mauritius heat. Elevation when sitting, avoiding prolonged standing, and consistent hydration are the practical management approaches. Sudden significant swelling involving the face and hands, particularly with headache or visual disturbances, is a warning sign for preeclampsia and requires same-day medical contact.
Sleep at 29 weeks is genuinely more difficult than at any previous point in the pregnancy. The combination of the growing bump limiting comfortable positions, the frequency of bathroom visits, the baby whose active periods do not consistently coincide with your sleep hours, heartburn worsening when lying flat, leg cramps, and the general physical discomfort of the third trimester all contribute to fragmented sleep that improving sleep habits alone cannot fully resolve. Left-side sleeping with a pillow between the knees and another supporting the bump is the most comfortable and clinically appropriate position. Rest when full sleep is not achievable.
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Antenatal appointments in the third trimester
From week 28 your antenatal appointments are typically scheduled every two to three weeks rather than monthly. Your gynaecologist will confirm the specific schedule for your pregnancy. These more frequent appointments monitor blood pressure, fundal height, fetal position, and the overall progression of the pregnancy more closely as the birth approaches.
Blood pressure monitoring is particularly important through the third trimester because preeclampsia most commonly develops in this period and is identified through a combination of elevated blood pressure and other signs. Each appointment includes a blood pressure check, and any reading your gynaecologist considers elevated will be addressed promptly.
Around week 32, most Mauritius gynaecologists schedule a growth scan to assess the baby’s size, position, and the placenta and amniotic fluid volume. This scan is not routine in all countries but is standard practice in many Mauritius clinics. Ask your gynaecologist at your next appointment when yours is scheduled.
Nutrition at 29 weeks
The third trimester is the period of highest nutritional demand, and the habits established through the second trimester need to be maintained and in some areas intensified.
Iron is the most critical priority. The blood volume expansion of pregnancy reaches its peak in the third trimester and iron demand is correspondingly highest. Anaemia at this stage affects your energy, your capacity to cope with delivery, and your baby’s own iron stores at birth. Continue pairing plant-based iron sources with vitamin C at every meal. If your most recent blood test showed low ferritin or haemoglobin, address it with supplementation as advised by your gynaecologist rather than through diet alone.
Calcium is drawn on most heavily in the third trimester as your baby’s skeleton grows at its most rapid pace. The calcium your baby needs comes from your diet or from your own bones. Including a calcium-rich food at least once daily is the minimum: milk, yoghurt, cheese, calcium-set tofu, tinned sardines with soft edible bones, and dark leafy greens are all accessible in a Mauritius kitchen.
DHA from oily fish is incorporated most actively into your baby’s brain tissue during the third trimester, when brain growth is at its most rapid. Including oily fish from the local market several times a week is one of the most directly beneficial dietary choices available for your baby’s neurodevelopment through the weeks ahead.
Protein at every main meal continues to be essential as the rapid tissue growth of the third trimester draws heavily on amino acid availability. Latest research shows a required iron intake during the third trimester of 1.5g/ body mass/ day. To ease up, a palm-sized serving of fish, chicken, eggs, lentils, beans, or dairy at each meal provides what is needed without requiring elaborate preparation.
Fibre alongside consistent hydration manages the constipation that tends to worsen in the third trimester as the uterus places further pressure on the digestive organs. Oats, lentils, beans, vegetables, and fresh fruit daily alongside adequate water are the most practical consistent sources.
Hydration in the Mauritius heat remains more important than standard guidance accounts for. Consistent access to water throughout the day, supplemented by the fluid content of soups, fresh fruits, and coconut water, together meet the elevated requirements of this final trimester.
Preparing for birth and the weeks ahead
The third trimester is the window for practical birth preparation, and week 29 is the right moment to begin in earnest if you have not already.
Your hospital bag should be assembled and ready by week 36. Beginning to gather items now, while the energy of the late second trimester is still partially available, prevents the alternative of a rushed assembly in week 37 when physical discomfort has increased significantly. The nutura.org hospital bag guide covers what each Mauritius clinic provides and what to bring specifically for the local context.
Breastfeeding preparation in the third trimester significantly improves outcomes in the critical first 48 hours after birth. Reading the nutura.org breastfeeding basics article, identifying a lactation consultant and saving the contact before the birth, and discussing your intentions with your gynaecologist so they are on your birth record are all achievable in the coming weeks.
Birth preferences are worth discussing with your gynaecologist in the coming weeks. Not a rigid plan, because birth does not always follow plans, but a clear understanding of what your preferences are around pain relief, intervention, and the immediate postpartum period gives you the vocabulary to communicate with your gynaecologist and the medical team rather than navigating these decisions for the first time in labour.
When to contact your clinic
The third trimester brings a lower threshold for contacting your gynaecologist, not because more is going wrong but because prompt attention matters more as the pregnancy approaches its end. Contact your gynaecologist the same day for heavy vaginal bleeding, significant or one-sided abdominal pain, regular or intensifying contractions, leaking fluid from the vagina, fever, sudden severe shortness of breath, severe headache with visual disturbances or swelling of the face and hands, a significant sustained change in your baby’s movement pattern, or any symptom that feels clearly wrong. Do not wait overnight.
The third trimester stretches from this week to birth, which is now approximately eleven weeks away for most women reading this at 29 weeks. The weeks ahead bring your baby’s most rapid weight gain, the final organ maturation that prepares every system for life outside the womb, the growth scan at week 32, the increasing physical demands of late pregnancy, and the birth preparation that becomes more urgent with each passing week.
The second trimester you have just completed was an extraordinary period of development. The third trimester you are entering now is where the final, decisive preparation for birth happens. Both for your baby and for you.
References: NHS — You and your baby at 29 weeks pregnant. nhs.uk. American College of Obstetricians and Gynecologists — Third trimester prenatal care. acog.org. World Health Organisation — Antenatal care recommendations. who.int. Tommy’s — 29 weeks pregnant. tommys.org. Ministry of Health and Wellness Mauritius — Antenatal care guidelines.
Disclaimer: This article is for informational purposes only. Always consult your gynaecologist or midwife for guidance specific to your pregnancy. In the third trimester, contact your clinic promptly for any concerns about reduced movement, unusual symptoms, or anything that feels wrong. Do not wait overnight.