Childbirth - Future Prospects

There are many aspects of childbirth that as yet are poorly understood. For example, why do women miscarry?

To understand this it is essential to investigate the role of the placenta and the various hormones that maintain pregnancy. Research in this field will often involve large animals, particularly sheep and monkeys. Measuring hormone release in small rodents is extremely difficult. This does not mean that mice can not be used in studies of reproductive mechanisms - only that they will be used in a different way. Monkeys are particularly helpful when trying to paint a picture of all the bodily changes that occur during pregnancy because they are one of the few mammals that visibly menstruate.

The Hammersmith & Queen Charlotte's hospital in London is trying to understand one cause of stillbirths. Abnormal liver function is the cause of as many as one in five cases. Cholestasis of pregnancy (obstetric cholestasis), for example, occurs when the mother's liver fails to secrete bile salts properly, causing itch - usually during the second half of pregnancy. The itch may be particularly annoying on the palms of the hands and soles of the feet. If it is persistent and there is no associated rash, women should have their liver function checked. The greatest risk is to unborn babies: they are unable to tolerate bile salts in their bloodstream. Studies on rat heart muscle cells suggest the bile causes irregular heartbeats. Delivering the baby early, at around 37 or 38 weeks helps prevent stillbirth. Several gene mutations have been linked to the cholestasis. The scientists now need to find out what the gene does by using mouse models with abnormalities in the same gene. Then they can look for treatments.

Symptoms of pre-eclampsia include high blood pressure [BMJ].

A number of important human studies are being carried out too. One is a collaborative project to study the genetics of pre-eclampsia (GOPEC). Funded by the British Heart Foundation, 1000 families affected by pre-eclampsia have provided DNA samples. The goal is to find the gene or genes linked to the condition. Once a gene connected with pre-eclampsia is found, it will be necessary to identify what that particular gene does - this will involve the use of animals.