Pregnancy Second Trimester

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(Week 13-26)

Week 13 The woman’s uterus is becoming larger and is starting to rise out of the pelvis. The foetus can move its head quite easily.

Scan at 13 weeks gestation

Week 14 You’re a third of the way through your pregnancy! i The average pregnancy lasts 266 days or 280 days from the first day of last period.

Week 15 Screening for Downs syndrome is offered about now. A simple blood test is carried out first then further tests may be offered. On the basis of the blood test results the woman may opt for a Chorionic Villus sample or an amniocentesis which would diagnose Down's syndrome or other chromosomal abnormalities. However these diagnostic tests have a small risk of subsequent miscarriage. An alternative to blood tests is a nuchal translucency scan – a new type of scan which is offered by some larger hospitals. But again an amniocentesis would be required for firm diagnosis.

Week 16 The foetus now has toe and finger nails eyebrows and eyelashes. It is also covered with downy hair.The hair that will cover the baby until the last week or so of pregnancy - called lanugo - starts to form. This hair is very fine more like down and it probably serves as some form of insulation and protection for the skin.

Week 17 The foetus can hear noises from the outside world. It is very likely that by this stage the mother is visibly pregnant and the uterus is rising. It’s a secret no more!

Week 18 By this stage the foetus is moving around a lot - probably enough to be felt. The first movements are sometimes described as ‘butterfly’ or ‘bubble’ sensations, and get progressively stronger as pregnancy progresses. Towards the end they are more ‘footballer’ and ‘rugby player’.

Week 19 The foetus is now about 15-20cm long and weighs about 300g. Milk teeth have formed in the gums.

Week 20 You’re half-way through pregnancy now! Almost all mothers are offered a routine scan which is carried out between week 20 and 24 depending on your local hospital’s procedures. The foetus also now begins to develop a waxy coating called vernix. It has been hypothesised that it protects the baby's skin from dehydration in the womb. Without the vernix, the baby would have very wrinkled skin from constant exposure to the watery amniotic fluid that surrounds it.The scan can show the foetus in fine detail and often reveal if the baby is a boy or a girl. However not all hospitals offer to tell parents the sex of the child - and not all parents want to know.

Week 21 The mother may feel short of breath as her uterus pushes against her diaphragm leaving less space for the lungs.The mother may be offered another ultrasound scan around this time. The scan can check the baby´s spine internal organs and growth are normal.

Week 22 Senses develop: taste buds have started to form on the tongue and the foetus starts to feel touch.

Week 23 The skeleton continues to develop and bones that form the skull begin to harden - but not fully.

Week 24 You will probably be asked to attend an Antenatal check up and scan to check the babies’ position. At week 24 your baby born this early does sometimes survive. A baby born at 24 weeks may possibly survive but it would have severe breathing difficulties as its lungs would not be strong enough to cope. It would also be very thin lightweight and susceptible to infections.

Week 25 All organs are now in place and the rest of the pregnancy is for growth. Preeclampsia is a risk from here onwards.This potentially fatal condition causes high blood pressure protein in the urine and swelling caused by fluid retention. The causes are unclear but research suggests it may be linked to an immune reaction to the foetus or the placenta. If the condition is serious women may be advised to take drugs to lower their blood pressure and in some cases an early caesarean or induction may be performed. Serious complications of pregnancy

Week 26 The skin of the foetus is gradually becoming more opaque than transparent. Those kicks will be really strong now!