RECURRENT PREGNANCY LOSS
By Richard Taavon, MD, FACOG of Wendover OBGYN
Recurrent early pregnancy loss, occurring before the 20th week of gestation, is an emotionally traumatic experience, similar to stillbirth or neonatal death. Couples experiencing such a loss need empathy and understanding. Recurrent pregnancy loss (RPL) is also one of the most frustrating areas in obstetrics because as many as 50 percent of cases may not present a clearly defined cause and there are few diagnostic and treatment strategies. Approximately 15 percent of pregnant women experience sporadic loss of a clinically recognized pregnancy. Just 2 percent of pregnant women experience two consecutive pregnancy losses and only 0.5-1 percent have 3 consecutive pregnancy losses.
Although a frequent patient concern, there is no high quality evidence showing a relationship between RPL and stress. OB/GYNs and reproductive experts recommend a thorough evaluation to rule out treatable causes, which can be divided into six categories.
Previous Pregnancy Loss
RPL is often due to advancing maternal age and poor egg quality. The risk of pregnancy loss in a first pregnancy is 11-13 percent. After one pregnancy loss, this rate rises to 15-20 percent. After two or three miscarriages, the rate is 24-29 percent and 31-33 percent, respectively.
Your skilled reproductive or gynecologic surgeon can correct many anatomic abnormalities, whether acquired or congenital. These uterine abnormalities are responsible for 10-50 percent of RPLs, including fibroids, endometrial polyps, cervical insufficiency and uterine septum. Common tests for these conditions include ultrasound, hysterosalpingogram and saline sonogram.
Maternal production of antibodies, which can increase the formation of blood clots in the placenta, causes some pregnancy losses. Antiphospholipid Antibody Syndrome (APS) has been linked to poor obstetric outcome. 5-15 perecent of patients with RPL may have APS, which can be diagnosed through a series of blood tests. Treatment includes medications to prevent blood clots during pregnancy
Chromosome number and structure abnormalities accounts for at least 50 percent of early pregnancy loss. 3-5 percent of with couples have a chromosomal rearrangement, usually a balanced translocation.
This defect occurs when a portion of one chromosome attaches to a different chromosome. Because it’s balanced, the parent appears normal. When the genetic material is passed to the egg or sperm, the embryo has too much or too little genetic material, resulting in an abnormal embryo and subsequent miscarriage.
Chromosome abnormalities can be diagnosed through a karyotype blood test. Thrombophilias and fibrinolytic factors, blood clotting defects that can be inherited, are associated with increased formation of blood clots in women. The formation of these blood clots can affect both placental function and blood flow.
One treatment option to avoid recurrent miscarriage is In Vitro Fertilization (IVF) with chromosome embryo testing before placement in the uterus.
Endocrine factors may account for 15-60 percent of RPLs. Polycystic Ovarian syndrome (PCOS), poorly controlled thyroid disease and diabetes, and Hyperprolactinemia can lead to RPL. It’s important to diagnose and treat these disorders prior to conception as it can take several months to obtain normal hormone levels. Luteal phase defect is another hormonal disorder. Progesterone is required for successful implantation and pregnancy maintenance; therefore, disorders related to impaired progesterone production will likely affect pregnancy success. This condition is diagnosed by measuring the progesterone in the blood after ovulation. If levels are low, supplemental progesterone is prescribed.
RPLs can also be caused by lifestyle choices and other environmental factors, such as smoking, obesity, alcohol use, caffeine consumption, and exposure to anesthetic gases (nitrous oxide), arsenic, pesticides, lead and mercury. Women with a diminished ovarian reserve may have poor quality eggs that fail to develop after fertilization. Untreated Celiac Disease has also been associated with pregnancy loss. Certain organisms, including mycoplasma, ureaplasma, CMV, chlamydia, rubella, HPV, Toxoplasma, gondii and Listeria are more prevalent in women experiencing RPL. However, there is no evidence that these infections cause RPL and routine screening is not recommended. It’s important for couples with a history of RPL to see an OB/GYN specialist for proper evaluation.