unable to recruit in suitable time frame

This study is recruiting two groups of women over the age of 18; those who are pregnant and who have pre-eclampsia; and those who are pregnant but do not have pre-eclampsia. The aim is to test a new method of diagnosing and monitoring pre-eclampsia and thus prevent the long-term damage it can cause to the baby's health. Untreated, pre-eclampsia can lead to seizures in pregnancy (eclampsia) and may prove fatal for mother and child.

Currently the only effective treatment for pre-eclampsia is control of the mother's blood pressure until it is safe to deliver the baby. The timing of delivery is kept under constant review by the medical team, who must balance the risk to the mother of developing eclampsia against the risk to the baby of being born too early (premature).

If pre-eclampsia can be diagnosed early, there is a greater chance of being able to treat it effectively. We know that women with pre-eclampsia often have exaggerated reflexes in their limbs (hyperreflexia) and that this may be linked to the risk of seizures. Measuring these reflexes might therefore be a useful way to diagnose and monitor pre-eclampsia, but doing this is not easy, so we want to assess whether measuring other reaction times might similarly help assess the risk of seizures. One possibility is by measuring the reaction time as we flick our eyes to follow a moving target, using an instrument called a saccadometer, which is worn on a head-band, a little like a head-torch.

By comparing the results between these groups and the non-pregnant women, we will be able to see if reaction times from the saccadometer are altered in women with pre-eclampsia, and, if so, whether saccadometry might be useful in helping doctors decide the best time for safe delivery.

Prospective feasibility study with two arms; (i) case-control comparisons of saccadic reaction time distributions between patients with preterm pre-eclampsia, age- and gestation-matched pregnant controls and age-matched female non-pregnant controls [cross-sectional analysis]; (ii) intra-individual comparisons of antenatal and postnatal saccadic reaction time distributions of patients with preterm pre-eclampsia [longitudinal analysis].

Inclusion criteria for cases:

1. Age ≥ 18 years
2. Confirmed diagnosis of pre-eclampsia, as defined by the International Society for the Study of Hypertension in Pregnancy (ISSHP)
3. Gestational age < 35+0 weeks
4. Participant is willing and able to give informed consent

Inclusion criteria for controls:

1. Age ≥ 18 years
2. Absence of essential hypertension and pre-eclampsia or pregnancy-induced hypertension in current and previous pregnancies
3. Gestational age < 35+0 weeks
4. Participant is willing and able to give informed consent

Exclusion Criteria:

1. Maternal neurological or psychiatric disorder (e.g. epilepsy, migraine, multiple sclerosis, depression, etc.)
2. Use of medication (other than vitamin supplements [cases and controls] and those for treatment or prevention of pre-eclampsia [cases]) during pregnancy

Pregnant patients with preterm pre-eclampsia diagnosed earlier than 35 weeks gestation (cases) and healthy age- and gestation-matched pregnant patients (controls)