Recurrent Pregnancy Loss

Recurrent pregnancy loss refers to the loss or miscarriage of two or more consecutive pregnancies. This can occur at any stage in the first 20 weeks of pregnancy but most miscarriages happen before the end of the first trimester (first 12 weeks). Miscarriages are not uncommon. It is estimated that every woman has a 15 to 30 percent chance of having a pregnancy end in miscarriage.

For women who have had one or two miscarriages, their chances of carrying their next pregnancy to full term remain about the same as if they had never had one. The chance of miscarrying again after three miscarriages increases with each loss. The risk for recurrent miscarriage also increases with age. Women 40 years or older with previous recurring miscarriages have a much higher risk compared to younger women.

Miscarriage Causes

Causes of miscarriage can include:

Genetic factors - problems with the genes or chromosomes of the fetus are the most common causes of miscarriage. These are usually not problems inherited from parents, but occur spontaneously, by chance, in the embryo. Less common, one or both parents can carry a genetic mutation that causes miscarriage.
Hormonal imbalances
Abnormalities of the uterus - associated with both first and second trimester pregnancy losses.
Congenital abnormalities - include double uterus and uterine septum. Other abnormalities include uterine polyps, fibroids and scar tissue inside the uterine cavity.
Cervical incompetence - complicates about one percent of pregnancies. Women with an incompetent cervix often have rapid miscarriages between 16 and 18 weeks. This condition can be successfully treated with a stitch to help hold the cervix closed.
Immunologic problems - antiphospholipid syndrome is the cause for recurrent miscarriage in 3 to 15 percent of women. It is recommended that women with recurrent miscarriage be tested for lupus anticoagulant and anticardiolipin antibodies to determine if they have this problem.
Excessive blood clotting in the placenta.