Knowing the rates and risks of miscarriage can assist in better preparation for a planned pregnancy. The abortion of a pregnancy before the 20th week is known as miscarriage, also called spontaneous abortion or early pregnancy loss. The rate of miscarriage can differ significantly among women because of various factors.
This article on ‘Understanding Miscarriage Rates For Planning Pregnancy‘ examines data on miscarriage rates, taking into account factors such as age, length of pregnancy, likelihood of miscarriage during assisted reproduction, and recurrent miscarriage rates.
What is the number of pregnancies that result in miscarriage?
Approximately half of the pregnancies may result in spontaneous abortion or pregnancy loss before the woman even realizes she is pregnant. Around 10 to 15% of recognized pregnancies end in a miscarriage according to research.1
Approximately 15% of pregnancies may result in miscarriage or fetal loss during the second trimester, which occurs between 13 and 19 weeks of pregnancy.2 Late miscarriages are often referred to as second-trimester miscarriages or fetal demise. A stillbirth, which occurs after 20 weeks of gestation, is not categorized as a miscarriage and is not included in miscarriage statistics.
Having healthy pregnancies after experiencing a miscarriage is possible and is a natural occurrence. It is important to acknowledge and accept this without letting emotions take over. The miscarriage rates mentioned do not include medical termination of pregnancy (MTP) or self-induced abortions.
When Does Miscarriage Occur?
The majority of miscarriages typically happen during the initial three months of pregnancy, which is also known as the first trimester, making up about 80-85 % of all cases.3 Within this timeframe, the highest number of miscarriages occur within the first seven weeks of pregnancy.
The likelihood of experiencing a miscarriage may vary at different stages of pregnancy, influenced by various factors related to both the mother and the fetus. Genetic issues, like chromosomal abnormalities in the fetus, can be a factor in early pregnancy losses. These factors are typically not within a woman’s control.
What is the rate of miscarriage for each week of pregnancy?
The rate of miscarriage can differ based on various factors in women. The likelihood of miscarriage during each week of pregnancy may vary.4
- 3-4 weeks: At this point, implantation takes place following the most recent menstrual cycle, causing pregnancy tests to show positive results. Between 50-75% of pregnancy loss occurs before a positive test result, indicating a chemical pregnancy, often accompanied by symptoms of pregnancy and miscarriage.
- Dr. Verma, a gynecologist and obstetrician, states that chemical pregnancies make up around 75% of all miscarriages. It is common for women experiencing a chemical pregnancy to not be aware of their pregnancy due to a regular or slightly late menstrual cycle. Nonetheless, some women may notice symptoms such as bleeding, cramping, or nausea.
- In the fifth week of pregnancy, the likelihood of a miscarriage is approximately 21.3% as reported in a study conducted in 2013. It is important to note that the risk of pregnancy loss can vary depending on various factors related to both the mother and the fetus.
- Between six and seven weeks of pregnancy, there is a 5% likelihood of miscarriage, which occurs at this stage when the fetal heartbeat becomes detectable.
- Between 8 and 13 weeks of gestation, the incidence of miscarriage decreases to approximately 2-4%. Between weeks 14 and 20 of pregnancy, the risk of experiencing a late pregnancy loss or miscarriage is as low as 1%.
What is the statistical occurrence of miscarriage rates based on age?
The rate of miscarriage tends to rise as individuals grow older. One possible explanation for the greater likelihood of pregnancy loss in older mothers could be the deterioration in the quality of the egg. Genetic defects in the form of chromosomal abnormalities are often present in the ovum. Studies have shown that the likelihood of pregnancy loss in women is influenced by their age, regardless of their past pregnancies.
Generally, the risk is at its lowest for women under the age of 19 and highest for those 45 years old and older.5
Miscarriage rates increase as women age.
The risk of miscarriage mentioned above is primarily determined by the age of the mother. Nevertheless, various other factors like chronic diseases, lifestyle choices, pregnancy complications, and hormonal fluctuations could also impact the likelihood of miscarriage.
The likelihood of miscarriage is a concern for couples undergoing in vitro fertilization (IVF)
There is a possibility of experiencing early pregnancy loss in 10-25% of IVF-ET cycles, which can have emotional, physical, and financial impacts on individuals as the pregnancy does not progress and may necessitate another round of IVF. A miscarriage shows that the embryo has successfully attached to the uterus. Another positive sign of pregnancy is a biochemical pregnancy, which is confirmed by a positive pregnancy test. Abnormalities in chromosomes could be a major factor contributing to spontaneous miscarriages in clinical settings.
Rate of recurrent pregnancy loss
Recurrent miscarriage6, also known as habitual abortion or repeated pregnancy loss (RPL), is when a woman experiences the loss of three consecutive pregnancies before reaching 20 weeks from her last menstrual period.
Approximately 1-2% of women may face multiple miscarriages, leading to physical and emotional exhaustion for many couples. Recurrent perinatal loss may result from genetic issues, autoimmune disorders, infections, anatomical issues, or other unidentified causes. Consulting with a specialist can assist in determining the underlying reason and appropriate treatment to ensure a successful pregnancy in the future.
Risk of Miscarriage Following Detection of Fetal Heartbeat
The rate of miscarriage decreases after the fetal heartbeat is seen on an ultrasound. Research indicates that there is a 10% decrease in the rate of miscarriage when the baby’s heartbeat can be detected.7
Some women may not realize the presence of the fetal heartbeat until the first prenatal ultrasound is conducted around the 11th or 12th week of pregnancy. Nonetheless, women who have received fertility treatment may have early scans to monitor the fetal heartbeat for any signs of potential miscarriage.
When is the likelihood of a miscarriage reduced?
The rate of pregnancy loss or miscarriage decreases as the pregnancy advances. The chance of miscarriage may begin to decrease as soon as the fetal heartbeat becomes detectable, which usually happens around 7 weeks into the pregnancy. However, a notable decrease in the miscarriage rate occurs after 12 weeks of pregnancy. Various other risk factors may also influence the decrease in miscarriage rates.
One example is that chromosomal abnormalities may lead to early pregnancy loss, while maternal conditions such as fibroids could be a contributing factor in later miscarriages.
What actions should you take if you have a miscarriage?
If you have a miscarriage, you should seek advice from a gynecologist or another medical professional. They can provide the necessary care or assist in determining the cause of the pregnancy loss and finding a solution.
In certain instances, the entirety of the pregnancy tissue may not be discharged during a miscarriage. To ensure a complete miscarriage, an ultrasound may be necessary for confirmation. If any remnants of tissue remain in the uterus, your doctor may recommend treatment to eliminate them and prevent potential complications. The rates of miscarriage by week can differ based on various factors concerning the mother and fetus.
However, if you experience heavy bleeding and symptoms of infection while pregnant, it is crucial to promptly seek medical help. Your healthcare provider might recommend preventive actions like giving Rh immunoglobulin if you have Rh-negative blood type to minimize complications in future pregnancies.
Key Pointers of ‘Understanding Miscarriage Rates For Planning Pregnancy’
- The majority of miscarriages happen during the initial three months of pregnancy.
- It is advisable to see a gynecologist to determine the cause and receive prompt treatment.
- Recovering from a miscarriage requires patience, therefore it is important to consult with a doctor.
During pregnancy, it is important to know the necessary precautions and when extra care is needed. Watch this informative video to understand the common timing and causes of miscarriages.
