It is widely accepted that natural human embryo mortality is high, particularly during the first weeks after fertilisation, with total prenatal losses of 70% and higher frequently claimed. So losses prior to biochemical pregnancy confirmation are high and women are unaware that she was ever pregnant. It is also known that about 15-25% of all clinically recognized pregnancies end in miscarriage. This is when pregnancy is confirmed on ultrasound or pregnancy tissue is identified after pregnancy loss. Compared to other animals, human beings suffer very high pregnancy failure rates after conception.
In the UK, recurrent pregnancy loss (RPL) is defined by having 3 or more failed clinical pregnancies while in other countries, 2 or more losses qualify as RPL.
Many pregnancies ending in miscarriage, a loss of life causes grief, depression and mourning. In the vast majority, no serious attempt is made to ascertain the cause. I think having two consecutive miscarriages warrants a full evaluation and for women over 38, a thorough investigation should begin, even after the first clinically recognized miscarriage.
Causes of Recurrent Pregnancy loss
There are many potential causes of RPL. Conventional medicine generally can only detect the cause in a maximum of 50% of cases, leaving the rest unexplained.
Most pregnancy losses are due to chromosomal abnormalities, which may come from the egg or the sperm. This relates to egg and sperm quality. Older women tend to have eggs with more chromosomal abnormalities. Karyotyping (determining the genetic makeup) of the products of conception can be helpful to see if there are chromosomal abnormalities in the fetus. Rarely, in approximately 2-5% of the cases, RPL would be due to parental genetic abnormalities such as balanced reciprocal translocations. If this is a concern, karyotyping of both partners can be done. If balanced translocation is found, genetic counselling is recommended.
Inherited thrombophilias (clotting disorders) such as mutations in Factor V Leiden, prothrombin, protein C, protein S, and anti-thrombin genes can be screened IF there is a personal history of venous thromboembolism in a non-provoked setting (no trauma/surgery). But routine testing of women with RPL for these genetic mutations is not currently recommended.
Antiphospholipid syndrome (APS) is thought to contribute on average to about 15% of RPL. APS is diagnosed using a combination of clinical and laboratory criteria. Women with persistent, moderate-to-high titers of antiphospholipid antibodies (>40GPL or MPL, or > 99th percentile) can be treated with a combination of prophylactic doses of unfractionated heparin and low-dose aspirin.
Anatomic factors are likely to contribute to about 10-15% of RPL. These factors include the septate uterus, scar tissue, uterine intramural fibroid (>5cm) or any size submucosal fibroid; weak cervix (2nd trimester loss). Congenital uterine abnormalities are associated with second-trimester pregnancy loss, preterm labour, and an increased rate of C-section. These anatomic factors are evaluated by the use of hystosalpingograms, where x-rays are used to look at the fallopian tubes and uterus in conjunction with dye injected into the uterine cavity. Certain anatomic factors can be corrected surgically.
Hormonal & Metabolic Factors. Most conventional doctors will do a very basic screen for thyroid, diabetes, and prolactin problems. Some sources estimate these hormonal factors contribute to about 20% of RPL. This can be treated by correcting the hormonal imbalance.
Infections. This is an area that still requires more research. Ureaplasma urealyticum, mycoplasma hominus, chlamydia, and other pathogens have been identified more commonly in vaginal and cervical cultures from women with sporadic miscarriages. There is still controversy whether treatment of infection is clinically helpful.
Environmental / Toxins: Studies show that increased risk of pregnancy loss is associated with obesity, alcohol consumption, smoking and substantial coffee drinking more than 3 cups a day
Can IVF bypass the above factors of miscarriage and give you a baby?
- A common idea is that IVF will be the solution irrespective of the cause of infertility. However, the primary role of IVF is to fertilize the egg by sperm and transfer the embryo into the uterus.
- In women with recurrent miscarriages, the egg has been fertilized, conception took place but the cause of miscarriages has not been identified or addressed.
- In cases of recurrent miscarriage, many of the acknowledged causes respond to other treatments and IVF plays no significant role in increasing the likelihood of carrying the embryo to full term.
- Patients suffering from recurrent miscarriage have no problem conceiving, the problem may lie in the implantation and development of the embryo and neither of these is influenced by IVF.
- Undergoing ovarian hyperstimulation and embryo transfer and enduring a two-week wait does not promote the environment for sustaining the embryo.
- It is common for extra procedures to be suggested as additions to the basic IVF process.
- Then do IVF plus heparin, steroid, progesterone, endometrial scratching …. increase your chance of having a baby? Studies say not.
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Studies show that steroid treatment for IVF problems may do more harm than good.
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A 2015 paper showed that for patients with RPL associated with translocation, Pre-implantation genetic screening (PGS) performed alongside IVF showed no improvement in live birth rates or time to pregnancy compared to natural conception.
- Pre-implantation genetic screening (PGS) offered by reproductive endocrinologists to couples having in vitro fertilization (IVF), has not lived up to its promise of improving rates of implantation, pregnancy rate or live birth rates.
Most Women With RPL Will Eventually Have a Healthy Live Born Baby
It’s important to remember that most women with RPL have a good chance of eventually having a successful pregnancy, whether or not a cause is discovered and treatment initiated. In one study, the overall live birth rates after normal and abnormal diagnostic evaluations for RPL were 77 and 71 per cent, respectively. In another, eight of 17 women with six or more consecutive unexplained miscarriages subsequently had a successful pregnancy.
What people do not realize is men’s damaged sperm play a significant role in miscarriage and I always feel much can be improved/ modified in men’s health and lifestyle. So Commit to your self-care and keep trying with better sperms!
Links:
I really enjoyed the lecture by Lesley Regan on Recurrent miscarriage
How men’s damaged sperm could play a significant role in recurrent miscarriage
The male contribution to recurrent pregnancy loss
