Engagement of your Baby’s Head

What does engagement of my baby’s head mean?

Your baby’s head is engaged when the widest diameter of your baby’s head is below the brim of your pelvis.

A pregnant woman will often know her baby “has dropped” (is engaged) because of a very intense feeling of fullness in her pelvis. She also aware the height of uterus is less and there is now a gap between the bottom of her rib cage and her uterus. As a consequence she will be aware she has less indigestion and heartburn and it is easier to eat and even to breath.

engagement_thumb_thumbSometimes a baby’s can be engaged one day and not the  next. It all has to do with the relationship between the size and position of your baby’s head, the size and shape of your pelvis and how firm your uterus is in pushing your baby’s head into your pelvis in pregnancy.

In your second and subsequent pregnancy the uterus is often “looser” and so there is often no reason for your baby’s head to be engaged before you are in labour.

When does engagement happen?

In your first ongoing pregnancy I don’t worry whether your baby’s head is engaged until the end of pregnancy (36 weeks on). Engagement from 36 weeks is a positive sign that labour could start soon, and that you will have a good labour. Your baby’s head will usually remain engaged.

Before 36 weeks the baby’s head can be engaged for a time and then not be engaged. This is because your baby is smaller and so there is no reason why your baby’s head has to remain low in your pelvis.

Your baby’s head does not need to be engaged for you to go into labour. For the majority of who have had a vaginal delivery this is usually the case – baby’s head is not engaged in the pelvis at the onset of labour.

If your are in your first ongoing pregnancy and your baby’s head remains high (not engaged) at 40 weeks it is a concerning sign that you will go overdue and that your baby’s head may not fit easily through your birth canal during labour. It is suggestive of an occipito-posterior position (baby looking up rather than down) and a more difficult and prolonged labour. It also indicates you are at greater risk of an obstructed labour and Caesarean section in labour may be needed as your baby doesn’t fit through your birth canal.

Close application of the foetal head to the cervix will help the cervix to ripen for the onset of labour. Alternatively if the foetal head is high and not well applied to the cervix then it is more likely for a woman to go overdue with an unfavourable cervix.

Posted by Dr Gary Sykes on -