Miscarriages Explained: What Causes Pregnancy Loss?

Miscarriages can feel completely devastating, no matter the date your pregnancy ended. It’s important to give yourself grace during this difficult period, but it’s also important to understand the causes and commonality of miscarriages, as part of your healing process.

Miscarriages occur in about 15-25% of all clinically recognized pregnancies — that’s almost 1 in 4!

It’s a deeply personal topic that isn’t often discussed — which does a disservice for those who experience miscarriage — because while it can feel isolating and lonely, it is very common.  Also, in actuality and for the majority of the time, it does not indicate a significant issue!

Want to hear some encouraging news? The likelihood of your next pregnancy being a perfectly healthy one is 76%! Now those are some great odds!

What are miscarriages?

Miscarriages are defined as the spontaneous loss of a pregnancy, often for unknown reasons. The embryo will stop developing, due to various issues, ranging from genetic abnormalities to abnormal hormone levels.

There are three different types of miscarriages: pre-embryonic, embryonic, and fetal.

• Pre-embryonic miscarriages occur from the date of conception until about the end of week 4, around implantation. Often times these are associated with implantation issues, perhaps from a thin uterine lining or low progesterone.
• Embryonic miscarriages occur weeks 5-9 during the beginning of organ generation and as oxygen and nutrients begin crossing the placenta. The causes of this tend to generally be genetic issues or low progesterone issues.
• Fetal miscarriages occur from weeks 10 until delivery, when maternal blood contact is fully established. These can occur for a variety of reasons, typically being anatomical issues, autoimmune attacks, or due to blood clotting issues.

The majority of miscarriages occur during the pre-embryonic and embryonic stages and commonly are associated with a genetic mismatch, often having little to no correlation with issues in future pregnancies.

What causes a miscarriage?

Miscarriages can occur for a variety of reasons. Often it’s hard to know what actually caused the miscarriage, but below are common causes:

• Progesterone Deficiency: for the first 6 weeks of pregnancy progesterone is only secreted by the corpus luteum (the ovarian remnants after ovulation) and is secreted in response to the pregnancy hormone hCG. Sometimes, if progesterone levels are not sufficient, it could result in a miscarriage. However, it’s important to note that supplemental progesterone will only assist in preventing miscarriages due to low progesterone levels.
• Antiphospholipid antibody syndrome: This is something your doctor can test your blood for, should you experience multiple pregnancy losses.
• Luteal Phase Insufficiency: When the luteal phase (second half of your cycle) is less than 10 days, a period can begin before a fertilized egg has a chance to implant in the endometrium. This can be corrected. Consider working with an OB/GYN or naturopathic doctor to improve your luteal phase length if this is an issue for you.

Other causes of miscarriage may include chromosomal structural abnormalities, issues with sperm quality, infection, uterine abnormalities that impede implantation, diabetes mellitus (uncontrolled), anatomic abnormalities, immunologic issues, and other unknown causes.

Signs of Miscarriage

Miscarriages are different for each person. For some it may begin with mild to severe cramping or bleeding and passing of tissue; others may not know they have miscarried until a heartbeat is not seen on an ultrasound. Because pregnancy hormones, such as progesterone, begin to decrease when a miscarriage occurs, some may notice a decrease in their BBT due to the absent thermal effects of progesterone.

When To Seek Help

While you should always go see your doctor if you think you are having a miscarriage, the following cases are considered “recurrent pregnancy loss” and should definitely be investigated by your doctor:  if you’ve experienced 2 miscarriages without a live birth or experienced 3 losses and had a live birth. Your doctor may begin with some genetic testing and blood testing to see if you have an autoimmune or clotting disorder that can be corrected, so you can successfully sustain a pregnancy.  Either way, it’s a great time to seek out some extra help and support!

TTC After a Miscarriage

Pregnancy loss can throw your hormones for a loop! Depending on how far along your pregnancy was before you experienced a miscarriage, this can affect how your body recovers. Those that were further along or had to have a D&C procedure, for example, may take a longer time for their hormones to regulate and begin cycling regularly again.

When you’ve taken time to recover both physically and mentally, starting ovulation testing and BBT testing back up is a great idea! You can keep an eye on what your body is doing while your hormones re-regulate. Many women tend to wait one full menstrual cycle at least before TTC again, but it’s completely up to you and your doctor!

Keep in mind, it may take weeks to months for your body to re-regulate. Utilize this time to practice good self-care, replenish your nutrient stores, get lots of rest, and take time to implement stress reduction practices such as yoga, therapy affirmations or meditations! Focus on being patient with your body as it finds its rhythm again, and log as much information about your cycles as you can in your Premom app!

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