Trial of the Efficacy of Intravenous Immunoglobulin for Treating Women With Unexplained Secondary Recurrent Miscarriage

Inclusion Criteria: * 4 or more miscarriages before the end of gestational week 14 in patients with secondary recurrent miscarriages. * At least three of these must be consecutive after the previous birth * At least two of the miscarriages with the present partner. Exclusion Criteria: * Age below 18 or above 41 years at conception * Significant uterine anomalies detected by hysterosalpingography, hysteroscopy or hydrosonography. * Significant chromosomal aberrations in the couple * Menstrual cycle \< 23 or \> 35 days * Presence of lupus anticoagulant or IgG anticardiolipin concentration \>= 40 GPL ku/l or plasma homocystein \>= 25 microg./l by repeated measurements at 8 weeks intervals * Tests positive for HIV or tests indicating carriage of hepatitis B or C * IgA deficiency * Allergy to albumin, IvIg or one of the substances added to preserve the drugs. * Presence of chronic disease, which necessitate permanent treatment with e.g. corticosteroids , non-steroidal antiinflammatory drugs, anticoagulation, simvastatin or imurel from the start of pregnancy. * Less than 2 of the previous pregnancy losses documented by ultrasound or uterine curettage. * Present pregnancy a result of donor insemination or egg donation. * Planned administration of gestagens or estrogens from the beginning of pregnancy. * 3 or more previous IVF/ICSI/FER attempts resulting in chemical pregnancy/miscarriage. * Previous participation in the trial.