Repeat Pregnancy Loss Definition
Repeat Pregnancy Loss (RPL) is medically defined as three or more losses that occur after the pregnancy has been confirmed via a blood test. These losses are heartbreaking, and yet it is often the case that little is understood about what is causing them. We know that roughly half of all pregnancies result in a miscarriage, and a majority of these are due to chromosomal abnormalities. Statistically one should expect to carry a baby to full-term within 2 or 3 pregnancies. 3 or more miscarriages suggest there are other contributing factors.
What are those factors?
A thorough evaluation is essential. While an official diagnosis of Repeat Pregnancy Loss requires at least three losses, often a work-up will begin after only two miscarriages, especially in women over 35 or for any woman who has been trying to conceive for more than a year. It is imperative to have a comprehensive work-up done by a fertility expert who is knowledgeable about the many causes of pregnancy loss and can properly order labs, evaluate the results, and recommend effective treatment options.
1. Embryo quality issues and chromosomal abnormalities
In order for a baby to grow, the baby’s cells must multiply and divide without the DNA making mistakes. DNA issues may come from the egg or the sperm. Age is the one factor that affects every egg and sperm. As DNA gets older, it becomes “sticky”, and is more prone to making mistakes during the replication process.
Imagine a piece of chewing gum stuck in your hair. You try to pull out the gum, and many broken strands of hair are stuck to it. That’s what happens to the DNA strands: they get stuck together, and when it is time for the DNA to divide, some pieces of DNA break off resulting in too much DNA in one cell, and not enough DNA in another cell. One can assess the risk of chromosomal issues via an array of testing that can be done to evaluate the health of both eggs and the sperm.
Sperm quality issues
Above and beyond quantity and motility, sperm need to have healthy DNA. As a gentleman becomes older, his sperm may have DNA that is more prone to damage. It is possible to have sperm that look great in a standard semen analysis, yet upon more in-depth analysis the DNA is abnormal. A workup is done through a male fertility specialist, either a reproductive urologist or an IVF clinic.
Egg quality issues
As an egg gets older, it’s DNA will become more fragile. Levels of various reproductive hormones are correlated with the aging process of the egg, and testing can help screen for the risk of chromosomal issues. A blood test is done on a specific day in the menstrual cycle, cycle day 2 or 3, for the following hormones:
- FSH – follicle stimulating hormone
- AMH – anti-Mullerian hormone
- LH – luteinizing hormone
- Prolactin – prolactin
2. Thin uterine lining
If the uterine lining is too thin the embryo will not have enough soil in which to grow roots. Either the lining will be too thin for the embryo to implant, or if implantation does occur, the placenta will ultimately be unable to support the proper growth and development of the baby. A thin lining will be detected via ultrasound, preferably measured within a few days of ovulation.
The lining may be too thin for a variety of reasons:
- poor nutrition leading to insufficient blood production
- poor blood flow to the uterus
- scar tissue
- Structural issues
3. Structural issues with the uterus
The uterus may have structural abnormalities that will interfere with a healthy uterine lining, resulting in the improper development of a placenta, and leaving an embryo unable to receive sufficient nourishment.
Structural issues might include:
- uterine fibroids
Diagnosis is done via imaging, including an ultrasound, saline sonogram, or a hysterosalpingogram.
4. Low thyroid levels
Thyroid hormones are needed to support a healthy pregnancy, and low levels of thyroid hormone can lead to early miscarriage. The need for thyroid hormones increases significantly during pregnancy. Often thyroid issues go undiagnosed as the standard pre-conception screening of thyroid hormones, typically just a TSH (thyroid stimulating hormone), will look normal.
A more comprehensive thyroid panel will offer better insight into a lurking thyroid issue:
- TSH – thyroid stimulating hormone
- Total T4
- Free T4
- Free T3
- TPO Ab – Thyroid Peroxidase Antibodies
- TG Ab – Thyroglobulin Antibodies
5. Blood clotting issues
Blood clotting issues can inhibit proper blood flow to the baby, leading to intrauterine growth retardation (IUGR), or fetal death. Blood clots may also dramatically compromise the health of the mother. Diagnosed via blood testing, there are a large number of markers that need to be evaluated by specialist, such as a peri-natologist (someone who specializes in high-risk pregnancies). If properly diagnosed, blood clotting issues can be effectively treated.
6. Autoimmune diseases
The immune system plays a vital role in allowing an embryo (aka a foreign invader) to stay put in the uterus, and an autoimmune disease can disrupt a healthy pregnancy.
A partial list of conditions thought to have an autoimmune component:
- Hashimoto’s thyroiditis
- Premature Ovarian Insufficiency
- unexplained infertility
- Repeat Pregnancy Loss
- Type 1 diabetes
- Rheumatoid Arthritis
- Irritable Bowel Syndrome
- some blood clotting disorders
- celiac and non-celiac gluten sensitivity
Diagnosis is typically done via blood testing. In the case of autoimmune diseases, one needs to manage both the immune system and any issues directly related to the autoimmune disease, i.e. thyroid hormones with hashimoto’s disease. The most effective approach for managing autoimmune disorders is a collaboration between conventional health care, and holistic, functional medicine.
A healthy pregnancy is possible
The many causes of Repeat Pregnancy Loss, once properly diagnosed, can usually be resolved so that one may go on to have a healthy, full-term pregnancy. Treatments can range from surgery, prescription medication, acupuncture, and nutritional approaches. An effective treatment protocol may include a combination of the above strategies. I will go into more detail on treatment strategies in future blogs. The first step is a thorough evaluation by a fertility specialist.
We guide our patients through this diagnostic journey, both through our own clinical services and with appropriate referrals to other specialists. If you live in the San Francisco Bay Area and would like to make an appointment, please learn more about our services, contact us, or book online.