In a series of 61 patients with the relapsing variety of chronic inflammatory demyelinating polyneuropathy, there were 16 women of childbearing age, 9 of whom became pregnant. In 4 of these women, the onset of neuropathy occurred in pregnancy and in the other 5 relapses occurred during pregnancy. There was a significant increase in the number of relapses during the year of pregnancy, and a tendency for symptoms to worsen during the third trimester or immediate postpartum period. It is concluded that there is an increased risk of relapse of chronic inflammatory demyelinating polyneuropathy in pregnancy.

Alpha-1 Antitrypsin, the major circulating protease inhibitor, has more than thirty alleles that can be identified by electrophoresis. In addition to its role as a protease inhibitor, alpha-1 antitrypsin may regulate the immune response. As there is evidence that both the inflammatory polyneuropathies and multiple sclerosis have an immune basis, and that genetic factors influence susceptibility, we have determined the alpha-1 antitrypsin phenotypes (protease inhibitor types) of 63 patients with Guillain-Barré syndrome, 52 patients with chronic inflammatory demyelinating polyneuropathy, and 178 patients with multiple sclerosis. In all 3 groups there was a significant increase in the proportion of patients with the protease inhibitor type M3 allele.

A large family with autosomal dominant inheritance of peroneal muscular atrophy, associated with extensor plantar responses in some cases, has been studied. Onset was usually in the first two decades and spasticity was not a feature. Nerve conduction studies in 21 cases and light and electron microscope findings on six sural nerve biopsies were similar to those in hereditary motor and sensory neuropathy type II. (7 Neurol Neurosurg Psychiatry 1994;57:1343-1346 Hereditary motor and sensory neuropathy (HMSN; peroneal muscular atrophy; Charcot-Marie-Tooth disease) is a heterogeneous group of genetically determined, slowly progressive disorders of the peripheral nerves that may be associated with extensor plantar responses in about 5% of cases.' 2 Dyck and Lambert3 described eight patients in two kinships who had hereditary spastic paraplegia associated with peroneal muscular atrophy and this condition was subsequently classified as HMSN Type V.4 Harding and Thomas2 in describing 25 cases from 15 families, preferred the term peroneal muscular atrophy with pyramidal features.In the present report we describe the clinical, genetic, electrophysiological, and nerve biopsy features in a large kindred with peroneal muscular atrophy and extensor plantar responses. and stained in 1% osmic acid for 24 hours after which single fibres were teased out. Another section of nerve was prepared for electron microscopy by fixing in 3% glutaraldehyde in a 0 1 %-M cacodylate buffer for three hours, followed by 2% osmium tetroxide for one hour. Specimens were dehydrated in graded concentrations of ethanol and embedded in epoxy resin (Spurrs). Semithin sections, 0-5-10 ,um in thickness, were stained with toluidine blue. Ultrathin sections were mounted on copper mesh grids, stained with lead citrate and uranyl acetate, and examined in a Philips 201 electron microscope.Morphometric studies of myelinated fibres were performed on photomicrographs of toluidine-blue stained sections of two to three fascicles of each sural nerve; the numbers and diameters of the myelinated fibres were counted by a digitiser linked to a personal computer with a Sigma Scan software package programme. The numbers of unmyelinated fibres were counted and their diameters measured on electron micrographs at magnification x 7300 with the same system. The numbers of denervated Schwann cell subunits and collagen pockets were also counted.6 MOLECULAR GENETICSThe CMT1A region D17S122 locus duplication was determined as previously described.7

SUMMARY The effect of pregnancy on the relapse rate of multiple sclerosis has been investigated. Obstetric and relapse histories of 52 women with clinically definite multiple sclerosis were obtained; there were 101 pregnancies of which 85 were at risk of a multiple sclerosis relapse. By comparing the number of relapses in the pregnancy period (9 months of pregnancy and 6 months immediately post partum) with the number in non-pregnancy periods for the same women, no increased risk of relapse during the pregnancy period was demonstrated. However, of the relapses that did occur during the pregnancy period, there was a significant reduction in the number of relapses in the first and second trimesters.The propensity for the onset of multiple sclerosis to occur in the reproductive years and for the disease to affect a greater proportion of females implies that many people who have multiple sclerosis will also have pregnancies. Consequently questions arise from the concermed patient regarding the effect of pregnancy on disease course and the effect of the disease on the course and outcome of pregnancy. The present study addresses the effect pregnancy has on the course of multiple sclerosis and looks specifically at the effect of pregnancy on relapse rate. Methods