Why miscarriages happen at 8 weeks

A history of recurrent miscarriage calls for evaluation and management. At the Washington University Fertility and Reproductive Medicine Center, we perform a range of tests on both the mother, the father and the fetal tissue, when applicable.

These tests may include:. While oftentimes the reasons for miscarriage are not obvious, many patients go on to have a successful third pregnancy. However, if a cause is discovered, it may be easy to fix, and finding the cause at this point may prevent further losses and emotional stress. After two miscarriages, you have what is known as recurrent pregnancy loss and you may benefit from the diagnostic testing noted above to see if there is a reason forwhy your are miscarrying.

However, there are times when some chromosomal abnormalities are repeatedly passed on which can contribute to multiple pregnancy losses.

If you have had two or more losses, you and your partner should consider a karyoptype to check for a balanced translocation. In some cases of recurrent pregnancy loss, in vitro fertilization with preimplantation genetic testing may be considered.

The logic being that the loss is likely due to a chromosomally abnormal embryo, therefore selecting a chromosomally normal embryo will increase my chances of live birth. This is highly individualized and should be considered in consultation with your physician.

For that reason, investigating products of conception after miscarriages is so important: If the products of conception demonstrate a normal female 45,XX or normal male 46,XY karyotype, one can practically automatically assume that the mother must have an immune-problem. Things are, however, a little more complicated with the opposite assumption: For decades it has been assumed that, once products of conception are diagnosed as chromosomal abnormal, that must be the reason for the miscarriage.

This can, however, be a wrong assumption. For two reasons, such a conclusion is not always appropriate: A placental biopsy, as noted before, does not always reflect the fetal cell lineage; a placental biopsy demonstrating aneuploid cells, therefore, does not necessarily automatically denote that the fetus, arising from the embryonic cell lineage, is also chromosomal abnormal. In addition, however, data in the immunology literature suggest that maternal autoimmunity, in itself, may increase aneuploidy risks in her offspring.

One, therefore, in those circumstances can never be certain what came first, the egg or the chicken; i. Correct differentiation between chromosomal and immunologic causes of miscarriages is, of course, of great clinical importance: Unless passed down from a parent, true chromosomal abnormalities in a pregnancy are random events and, therefore unless a patient experiences repeat miscarriages not predictive of future miscarriage risk.

Immunological miscarriages, however, do denote automatic repeat miscarriage risk. Moreover, true chromosomal abnormalities, in a large majority of cases cannot be prevented from miscarrying since miscarriages are a protective mechanism of nature to prevent abnormal births and must not be prevented. In the next portion, we explain how to identify women at risk of early miscarriages. A world-renowned specialist in reproductive endocrinology, Dr. Gleicher has published hundreds of peer-reviewed papers and lectured globally while keeping an active clinical career focused on ovarian aging, immunological issues and other difficult cases of infertility.

Follow on LinkedIn. So, what causes early miscarriages at weeks? Normally, the early miscarriages are blamed on chromosomal abnormalities that result in the arrest of embryo growth and while that may be correct in some situations, it is not so for all. Miscarriages are caused by various factors at different times in the pregnancy and not knowing the reason can be frustrating.

To check the embryos for any aneuploidy chromosomal imbalance , the doctors recommend preimplantation genetic testing for aneuploidy PGT-A before embryo implantation. While it has proven highly useful, this technique is not always accurate because the cells that are tested do not always represent the whole embryo. The placenta and its precursor the trophectoderm tend to have more aneuploid cells and those are the ones tested with PGT-A. So, sometimes, despite being declared aneuploid by PGS testing, an embryo turns into a perfectly normal baby.

Chromosomal abnormalities of the embryo remain the most common cost of pregnancy losses in women but what else could be the reason of early miscarriages? Read below:. In normal situations, during a pregnancy the immune system is reprogrammed to accept this embryo. Up to 70 percent of first trimester miscarriages and 20 percent of second trimester miscarriages occur because of a glitch in the fetus's genes, according to the March of Dimes. During fertilization, the sperm and egg each bring 23 chromosomes together to create perfectly matched pairs.

This is a complex process, and a minor glitch can result in a genetic or chromosomal abnormality. While some chromosomal abnormalities are compatible with life such as trisomy 21, the most common type of Down syndrome , other chromosomal disorders are simply not. Miscarriages caused by chromosomal abnormalities happen more often in women older than The frequency of miscarriage in women below age 20 is around 12 to 15 percent and doubles as the woman approaches age There is nothing that can be done to prevent miscarriage due to a chromosomal abnormality and once a miscarriage has begun there is nothing one can do to stop it.

Whether it be hypothyroidism too low or hyperthyroidism too high , thyroid disorders can lead to problems with infertility or cause recurrent miscarriages. The Malpani Infertility Clinic's website explains that in cases where a woman's thyroid function is low, her body will try to compensate by producing hormones that can actually suppress ovulation. Conversely, a thyroid that is producing too many hormones can interfere with estrogen's ability to do its job, and it may make the uterus unfavorable for implantation or lead to abnormal uterine bleeding.

Zobel says. A less common cause of miscarriage can be physical problems with the mother, reports Dr. Nowacki, adding that this usually occurs in the second or third trimester.

Here are some examples:. A doctor can determine uterine defects through specialized X-rays before pregnancy. Most cases can be treated, which may reduce the risk of miscarriage.