What is it?
Any labour and birth that occurs before the 40th week of pregnancy is considered to be premature or preterm. Usually a pregnancy lasts around 40 weeks. If labour and delivery happen between the 20th and 37th week of gestation, it is considered premature.
There are several kinds of premature birth:
- Moderate to late premature birth: between the 34th and the 37th week of pregnancy;
- Very premature birth: between the 25th and the 33rd week of pregnancy;
- Extremely premature birth: before the 25th week of pregnancy.
What are the symptoms of a premature birth?
Babies born before full term tend to have a low birth rate and other symtoms depending on how early they are born.
It is important that the foetus stays in the uterus as long as possible, so that the organs will develop correctly (especially the lungs, brain and heart). The earlier the baby is born, the more severe the consequences will be. The baby, once born, may have respiratory problems, heart conditions, neurological conditions, gastrointestinal tract conditions, metabolic or immune system disorders.
From the 37th week on, the baby has everything he or she needs to be considered a fully developed foetus. However, this doesn't exclude the possibility of complications.
What causes premature birth?
The possibility of premature birth is linked to some elements in your pregnancy and medical history:
- having had a previous premature birth
- being pregnant with twins
- an interval of less than six months between pregnancies
- conceiving through in vitro fertilisation
- any problems or conditions in your uterus, placenta or cervix;
- smoking, alcohol or drugs consumption during the pregnancy
- amniotic fluid infections
- hypertension and diabetes
- being underweight before getting pregnant
- previous history of miscarriage
- physical injury or trauma
- uterine anomalies
How can it be prevented?
It is important to go to all your scans and checks during the pregnancy - especially those during the 31st and 32nd week, such as the transvaginal ultrasound, which can detect whether you have cervical insufficiency (your cervix is smaller than 2.5 or 2 centimetres). Cervical insufficiency is one of the main causes for spontaneous premature birth.