Non-Luer Butterfly Needle With One-way Valve for the Epidural Blood Patch: Does it Alter Blood Clotting?

Inclusion Criteria: * Participant is willing and able to give informed consent for participation in the study. * Male or Female. * Aged 18 years or above. * Within first 2 days postnatal for postnatal group * Healthy participants must be in good health. * Able (in the Investigators opinion) and willing to comply with all study requirements. * Willing to allow his or her General Practitioner and consultant, if appropriate, to be notified of participation in the study. Exclusion Criteria: * Any medical condition * In postnatal group, women with haemorrhage greater than 1L * In postnatal group, less than 12 hours post prophylactic dalteparin * Any clotting abnormality * On any medication including herbal medication (vitamins taken during pregnancy are acceptable) * Age less than 18 years at recruitment * Adults who are not capable of giving valid consent * Adults with learning disabilities/ difficulties * Adults in emergency situations * Unable to speak or read English * Prisoners * Adults unable to consent for themselves * Any person considered to have a particularly dependent relationship with investigators * Any others deemed to belong to a vulnerable group. * Any other significant disease or disorder which, in the opinion of the Investigator, may either put the participants at risk because of participation in the study, or may influence the result of the study, or the participant's ability to participate in the study. * Participants who have participated in another research study involving an investigational product in the past 12 weeks