This about making sure that the foetus is OK. This basically consists of cardiotocography (CTG) and if foetal distress is suspected, foetal blood sampling. It is also important to look after babies after birth. Mothers tend to get annoyed if you let them die. So some clever chap came up with something called an APGAR score which is detailed at the bottom of this page.
Foetal distress is a poorly defined term but essentially means signs that the foetus's life is compromised unless something is done soon.
All mothers who have babies in hospital have periodic foetal heart rate monitoring. This is using a Doppler ultrasound. Continuous fetal heart rate monitoring is NOT indicated in normal labour with no associated risk factors and is only used when there is a reason to. It is only an indirect guide to the health of the foetus but since it is one of the few ways of being able to tell, many treat it as a direct monitor.
Having said this, there are a variety of indications for CTG and they can be split into three different sections: risks in the mother, risk to the foetus and risks during labour.
- Foetus - IUGR; prematurity; multiple pregnancy; breech presentation; meconium
- Labour - augmentation; epidural; vaginal bleeding; fever; meconium
Classification of findings
Obviously, management is affected by CTG findings. The findings are classified into reassuring, non-reassuring and abnormal which in turn are used to describe the CTG as normal, suspicious or pathological The following table classifies CTG findings:
|Baseline Heart Rate||Heart Rate Variability||Decelerations||Accelerations|
|Non-reassuring||100-109/161-180||<5 for 40-90 mins||Early/variable/single prolonged <3mins||Absence in presence of other findings|
|Abnormal||<100/>180/sinusoid (S-shaped) >10 minutes||<5 for >90mins||Late/atypical variable/single prolonged >3mins||As above|
Essentially, a normal CTG means that all four categories are normal. Suspicious CTGs have 1 non-reassuring feature and pathological is anything else i.e. >1 non-reassuring/1 or >1 abnormal.
Suspicious CTGs have four main causes: poor quality, uterine hypercontractility, infection and other maternal adverse factors. These factors have to be considered before deciding that the foetus is distressed. A pathological CTG requires the following:
Foetal Scalp Blood Sampling
Essentially, blood is taken from the presenting head of the foetus. I can't put a copyrighted image on the website but I can link to it and this one gives you and idea of what's going on. The tube is called an amnioscope which gives access to the foetal scalp. The value that you get is a pH measurement which is normally >7.25.
- pH <7.20 - deliver
- pH 7.20-7.25 - repeat in 30 minutes. If still abnormal, deliver.
The APGAR score is a set of criteria to measure a newborn's wellbeing and was developed over 50 years ago. It is done at 1 minute and 5 minutes following birth.
|Score of 0||Score of 1||Score of 2||Component of Acronym|
|Skin color||blue all over||blue at extremities
body and extremities pink
|Reflex irritability||no response to stimulation||grimace/feeble cry when stimulated||sneeze/cough/pulls away when stimulated||Grimace|
|Muscle tone||none||some flexion||active movement||Activity|
|Breathing||absent||weak or irregular||strong||Respiration|
The score is (and you'll have figured this out already if you're sharp on your arithmetic) out of 10.