Low dose weekly methotrexate in early pregnancy. A case series and review of the literature.
OBJECTIVE
To assess the teratogenic risk of low dose weekly pulses of methotrexate (MTX) inadvertently taken during the first trimester of pregnancy.


METHODS
We assessed pregnancy and neonatal outcome of 4 patients with rheumatic disease treated with weekly pulses of 5 to 15 mg of MTX for a mean duration of 4 years.


RESULTS
The 4 patients had continued MTX treatment from one to 6 weeks of gestation. One patient miscarried at Week 6, the other pregnancies ended with the delivery of healthy children. Chromosome analysis of one child was normal.


CONCLUSIONS
In spite of the absence of congenital anomalies in our cases, safe contraception in fertile patients who start low dose weekly MTX is mandatory.
Ostensen
M
M
Center for Mothers with Rheumatic Disease, Department of Rheumatology, University Hospital of Trondheim, Norway. oestensen@aol.com
Hartmann
H
H
Salvesen
K
K
D000014:Abnormalities, Drug-Induced / Q000209:etiology; D000022:Abortion, Spontaneous / Q000139:chemically induced; D000328:Adult; D018501:Antirheumatic Agents / Q000008:administration & dosage* / Q000009:adverse effects; D001172:Arthritis, Rheumatoid / Q000188:drug therapy*; D004305:Dose-Response Relationship, Drug; D005260:Female; D005493:Folic Acid Antagonists / Q000009:adverse effects*; D005865:Gestational Age; D006801:Humans; D008431:Maternal-Fetal Exchange; D008727:Methotrexate / Q000008:administration & dosage* / Q000009:adverse effects; D011247:Pregnancy; D011256:Pregnancy Outcome
D018501:Antirheumatic Agents; D005493:Folic Acid Antagonists; D008727:Methotrexate