The investigators want to test whether infusions of intravenous immunoglobulin - a blood product known to modify immune responses - in early pregnancy will increase the chance of a subsequent live birth in women with three or more miscarriages after a birth and a total of at least four miscarriages. This will be done in a trial where 82 patients will be randomly allocated to infusions with intravenous immunoglobulin or placebo during pregnancy.

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.