Progressive chronic hypoxia is a phrase that often appears in clinical negligence claims where an individual has acquired cerebral palsy as a result of mismanagement of his or her delivery.
When this situation arises in the uterus, the usual sequence of events is:
When a pregnant woman reports reduced fetal movements, it is very important to act on these findings, ideally with a period of CTG monitoring, to ensure that the baby is not ‘quiet’ due to any distress.
If the CTG shows extreme distress, or the terminal fetal heart rate pattern referred to above as the final stage of progressive chronic hypoxia, then an immediate caesarean section delivery is likely to be required.
If there are less severe problems identified on the CTG, then often the treatment plan will be to carry out an ultrasound scan and Doppler flow studies to look for the above-mentioned changes in umbilical artery resistance, loss of end-diastolic flow and reducing amniotic fluid. In the event that these investigations raise concerns and the baby is term (37 weeks gestation or more), it is extremely important to expedite delivery, either by induction of labour or caesarean section, depending on how extreme the presenting picture is.
Helen Hammond, associate in Penningtons Manches' clinical negligence team, comments: “Women in the late stages of pregnancy are urged to get to know their unborn baby’s normal pattern of movement, as this is different for every child, and to report any change. However, far too frequently reports of reduced fetal movements, or, just as importantly, a change in the pattern of fetal movements, are overlooked, potentially with life-shattering consequences. We urge treatment providers to be vigilant about this issue to ensure that as many unborn babies as possible are safely delivered into the world.”