At week 29, the fetal weight is just over 1.1kg and fetal length is approximately 39cm from crown to heel, showing a steady growth. Fetal weight is likely to triple between this week and birth, although fetal length will only increase by a relatively small amount. The head also continues to grow to accommodate the ever-developing brain and the muscles and lungs continue to mature throughout this week. Bones are also continuing to harden and approximately 200mg of calcium are deposited into the skeleton each day. Fetal movement is now becoming more restricted as there is less available space to move. The fetus is now less able to turn easily and movements tend to be somewhat smaller than in previous weeks.
Genitals are now fully developed. If the baby is male, the testicles will now have descended from the abdominal cavity –near the kidneys – and now rest in the scrotal sac. If the baby is female, the clitoris is clearly visible, as it is not yet covered by the labia, which are still developing. The labia will grow and cover the clitoris during the last few weeks of pregnancy.
Hair on the head continues to grow, as do eyebrows and eyelashes. Most babies respond to both external sound and light by the end of this week. The eyes now have pigmentation in the irises and are a grey/blue colour.
During the third trimester nutrition continues to play an important role in both your own, and your baby’s health. It is important to eat foods that are high in protein, vitamin C, iron and calcium. Your midwife can advice you on a healthy diet during pregnancy and can also prescribe any additional supplements that you may require.
Back ache is a common pregnancy-related symptom during the third trimester. If you are suffering from back pain, you may find it helpful to sit on the floor with your back straight against a wall and your shoulders pressed back. Many women also find massage beneficial. You should check that any massage oils you use are safe for use during pregnancy. Varicose veins are also common during this stage of pregnancy and are simple swollen blood vessels that can appear anywhere on the body but are most commonly seen on the legs. Some women experience only mild swelling and achiness while others report pain and bulging blue veins. Maintaining good blood flow by drinking plenty of water and taking gentle exercise can both help to alleviate the symptoms but you should consult your midwife if you have any concerns about varicose veins. Most women find that their varicose veins disappear after they give birth.
Many women also find that digestive discomfort, such as heartburn and trapped wind become more frequent during this stage of pregnancy. Eating small amounts of food throughout the day, as opposed to a couple of large meals, can help. Your midwife, Doctor or pharmacist will also be able to advise you about which antacids are safe to take during pregnancy. Digestive problems can also lead to problems sleeping. Avoiding eating too close to bedtime may help with this. You may also find that taking gentle exercise such as going for a walk during the day helps to promote a more restful night’s sleep.
Symptoms to watch out for
Pre-eclampsia, vaginal bleeding, premature birth and obstetric cholestasis are important complications in late pregnancy. Pre-eclampsia manifests as headaches, disturbances of vision, swelling particularly of the legs and face and upper abdominal pain. It can result in a small baby and the tummy being smaller than it should be. Bleeding form the vagina is abnormal in late pregnancy. Painful contractions can result in premature birth. Itching of the palms of the hands and the soles of the feet may be due to obstetric cholestasis which is a threat to the baby. More generalized itching is common and usually harmless.
What is routinely offered on NHS
Visits to the midwife or GP become more frequent in later pregnancy. The midwife or GP will ask about symptoms; taking the blood pressure and checking the urine. Referral will be made to the consultant as necessary.
What other care is available
In a private self referral clinic additional blood tests and ultrasound scans can be done at short notice with rapid reporting of results. The woman and her partner can see a consultant for opinion and advice. This is done at a convenient time and with plenty time for discussion.
Pregnancy-safe massage and reflexology are available. You can arrange to have a consultation with a pregnancy nutritionist.