RECURRENT PREGNANCY LOSS

RECURRENT PREGNANCY LOSS

Recurrent pregnancy loss is a disease* distinct from infertility, defined by two or more failed pregnancies. When the cause is unknown, each pregnancy loss merits careful review to determine whether specific evaluation may be appropriate. After three or more losses, a thorough evaluation is warranted.Although approximately 25% of all recognized pregnancies result in miscarriage, less than 5% of women will experience two consecutive miscarriages, and only 1% experience three or more.
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Couples who experience recurrent pregnancy loss may benefit from a medical evaluation and psychological support.
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Genetic/Chromosomal Causes

A chromosome analysis performed from the parents’ blood identifies an inherited genetic cause in less than 5% of couples. Translocation (when part of one chromosome is attached to another chromosome) is the most common inherited chromosome abnormality. Although a parent who carries a translocation is frequently normal, their embryo may receive too much or too little genetic material..
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When this occurs, a miscarriage usually occurs. Couples with translocations or other specific chromosome defects may benefit from pre-implantation genetic diagnosis in conjunction with in vitro fertilization..
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In contrast to the uncommon finding of an inherited genetic cause, many early miscarriages are due to the random (by chance) occurrence of a chromosomal abnormality in the embryo. In fact, 60% or more of early miscarriages may be caused by a random chromosomal abnormality, usually a missing or duplicated chromosome..
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Age

The chance of a miscarriage increases as a woman ages. After age 40, more than one-third of all pregnancies end in miscarriage. Most of these embryos have an abnormal number of chromosomes..
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Hormonal Abnormalities

Progesterone, a hormone produced by the ovary after ovulation, is necessary for a healthy pregnancy. There is controversy about whether low progesterone levels, often called luteal phase deficiency, may cause repeated miscarriages. Treatments may include ovulation induction, progesterone supplementation or injections of human chorionic gonadotropin (hCG), but there is no evidence to support the effectiveness of these treatments..
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Metabolic Abnormalities

Poorly controlled diabetes increases the risk of miscarriage. Women with diabetes improve pregnancy outcomes if blood sugars are controlled before conception. Women who have insulin resistance, such as obese women and many who have polycystic ovarian syndrome (PCOS), also have higher rates of miscarriage. There is still not enough evidence to know if medications that improve insulin sensitivity lower miscarriage risks in women with PCOS..
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Uterine Abnormalities

Distortion of the uterine cavity may be found in approximately 10% to 15% of women with recurrent pregnancy losses.Diagnostic screening tests include hysterosalpinogram, ultrasound, or hysteroscopy..
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Congenital uterine abnormalities include a double uterus, uterine septum, and a uterus in which only one side has formed. Asherman’s syndrome (scar tissue in the uterine cavity), uterine fibroids, and possibly uterine polyps are acquired abnormalities that may also cause recurrent miscarriages. Some of these conditions may be surgically corrected..
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