Recurrent miscarriage, habitual abortion, or recurrent pregnancy loss (RPL) is the occurrence of three or more consecutive pregnancies that end in miscarriage of the fetus before viability (for example 24 weeks gestation in the United Kingdom). About 1% of couples trying to have children are affected by recurrent miscarriage. There are various causes for recurrent miscarriage, and some are treatable. Some couples never have a cause identified, often after extensive investigations. A uterine malformation is considered to cause about 15% of recurrent miscarriages.
The most common abnormality is a uterine septum, a partition of the uterine cavity. The diagnosis is made by MRI or a combined laparoscopy hysteroscopy of the uterus. Also uterine leiomyomata could result in pregnancy loss. In the second trimester a weak cervix can become a recurrent problem. Such cervical incompetence leads to premature pregnancy loss resulting in miscarriages or preterm deliveries. A balanced translocation or Robertsonian translocation in one of the partners leads to unviable fetuses that are miscarried.
This explains why a karyogram is often performed in both partners if a woman has experienced repeated miscarriages. About 3% of the time a chromosomal problem of one or both partners can lead to recurrent pregnancy loss. Although patients with such a chromosomal problem are more likely to miscarry, they may also deliver normal or abnormal babies. Aneuploidy may be a cause of a random spontaneous as well as recurrent pregnancy loss. Aneuploidy is more common with advanced reproductive age reflecting decreased germ cell quality.