AMERICAN SOCIETY FOR REPRODUCTIVE MEDICINE …

                      AMERICAN SOCIETY FOR REPRODUCTIVE MEDICINE
          1209 Montgomery Highway · Birmingham, Alabama 35216-2809 · TEL (205) 978-5000 · FAX (205) 978-5005 · E-MAIL asrm@asrm.org · URL www.asrm.org



                                               PATIENT'S FACT SHEET
                                             Recurrent Pregnancy Loss
Recurrent pregnancy loss is the miscarriage of two or three con-                pregnancy losses. Diagnostic screening tests include hysterosal-
secutive pregnancies in the first or early second trimester.                    pingogram, sonohysterography (See Fact Sheets "Hysterosalpin-
Although approximately 25% of all recognized pregnancies result                 gogram," and "Saline Infusion Sonohysterography"), ultrasound,
in miscarriage, less than 5% of women will experience two con-                  or hysteroscopy. Congenital uterine abnormalities include a double
secutive miscarriages, and only 1% experience three or more.                    uterus, uterine septum, and a uterus in which only one side has
Couples who experience recurrent pregnancy loss may benefit                     formed. Asherman's syndrome (scar tissue in the uterine cavity),
from a medical evaluation and psychological support.                            uterine fibroids, and possibly uterine polyps are acquired abnor-
                                                                                malities that may also cause recurrent miscarriages. Some of these
Genetic/Chromosomal Causes. A chromosome analysis performed                     conditions may be surgically corrected.
from the parents' blood identifies an inherited genetic cause in less
than 5% of couples. Translocation (when part of one chromosome is               Antiphospholipid Syndrome. Blood tests for anticardiolipin anti-
attached to another chromosome) is the most common inherited                    bodies and lupus anticoagulant may identify women with
chromosome abnormality. Although a parent who carries a translo-                antiphospholipid syndrome, a cause for 3% to 15% of recurrent
cation is frequently normal, their embryo may receive too much or               miscarriages. A second blood test performed at least 6 weeks later
too little genetic material. When this occurs, a miscarriage usually            confirms the diagnosis. In women who have high levels of
occurs. Couples with translocations or other specific chromosome                antiphospholipid antibodies, pregnancy outcomes are improved by
defects may benefit from pre-implantation genetic diagnosis in con-             the use of aspirin and heparin.
junction with in vitro fertilization.
                                                                                Thrombophilias. Inherited disorders that raise a woman's risk of
In contrast to the uncommon finding of an inherited genetic cause,              serious blood clots (thrombosis) may also increase the risk of fetal
many early miscarriages are due to the random (by chance) occur-                death in the second half of pregnancy. However, there is no
rence of a chromosomal abnormality in the embryo. In fact, 60% or               proven benefit for testing or treatment of women with throm-
more of early miscarriages may be caused by a random chromoso-                  bophilias and recurrent miscarriage in the first half of pregnancy.
mal abnormality, usually a missing or duplicated chromosome.
                                                                                Male factor. Increasing evidence suggests that abnormal integrity
Age. The chance of a miscarriage increases as a woman ages.                     (intactness) of sperm DNA may affect embryo development and
After age 40, more than one-third of all pregnancies end in mis-                possibly increase miscarriage risk. However, these data are still
carriage. Most of these embryos have an abnormal number of                      very preliminary, and it is not known how often sperm defects
chromosomes.                                                                    contribute to recurrent miscarriage.

Hormonal Abnormalities. Progesterone, a hormone produced by                     Unexplained. No explanation is found in 50% to 75% of couples
the ovary after ovulation, is necessary for a healthy pregnancy.                with recurrent pregnancy losses.
There is controversy about whether low progesterone levels, often
called luteal phase deficiency, may cause repeated miscarriages.                Tests with no proven benefit for recurrent miscarriage include
Treatments may include ovulation induction, progesterone supple-                cultures for bacteria or viruses, tests for insulin resistance, antinu-
mentation or injections of human chorionic gonadotropin (hCG), but              clear antibodies, antithyroid antibodies, maternal antipaternal anti-
there is no evidence to support the effectiveness of these treatments.          bodies, antibodies to infectious agents, and embryotoxic factors.

Metabolic Abnormalities. Poorly controlled diabetes increases                   Treatments with no proven benefit include leukocyte (white blood
the risk of miscarriage. Women with diabetes improve pregnancy                  cell) immunization and intravenous immunoglobulin (IVIG) therapy.
outcomes if blood sugars are controlled before conception.
Women who have insulin resistance, such as obese women and                      Conclusion. A couple may be comforted to know that the next
many who have polycystic ovarian syndrome (PCOS), also have                     pregnancy is successful in 60% to 70% of those with unexplained
higher rates of miscarriage. There is still not enough evidence to              recurrent pregnancy losses. A healthy lifestyle and folic acid sup-
know if medications that improve insulin sensitivity lower miscar-              plementation is recommended before attempting another preg-
riage risks in women with PCOS (see Fact Sheet "Insulin                         nancy. Smoking cessation, reduced alcohol and caffeine consump-
Sensitizing Agents").                                                           tion, moderate exercise, and weight control may all be of benefit.
                                                                                Counseling may provide comfort and help cope with the grief,
Uterine Abnormalities. Distortion of the uterine cavity may be                  anger, isolation, fear, and helplessness that many individuals exper-
found in approximately 10% to 15% of women with recurrent                       ience after repeated miscarriages.

     The American Society for Reproductive Medicine grants permission to photocopy this fact sheet and distribute it to patients.
Created 2/2005