title: Amnifiltration in the first trimester: feasibility, technical aspects and cytological outcome.
abstract: An amnifiltration system has been developed which allows collection of cells from the amniotic sac in the first trimester of pregnancy whilst only removing 1 ml of amniotic fluid in total. The cells can be cultured and harvested, using the same methods as early amniocentesis, to enable prenatal diagnosis of fetal karyotype. A range of filters constructed from different materials and of differing pore sizes were examined for their ability to trap and subsequently release a maximum number of amniotic fluid cells. The best filter membrane was found to be a cellulose acetate filter of 0.8 micro m pore size. To achieve the same cytogenetic outcome as a 10 ml amniocentesis, a minimum of 20 ml amniotic fluid must be filtered and recirculated through the system.
authors.affiliation: Department of Obstetrics and Gynaecology, United Medical and Dental Schools, St. Thomas' Campus, London, UK.
authors.forename: D L
authors.initials: DL
authors.lastname: Byrne
authors.forename: K
authors.initials: K
authors.lastname: Marks
authors.forename: P R
authors.initials: PR
authors.lastname: Braude
authors.forename: K H
authors.initials: KH
authors.lastname: Nicolaides