What is a miscarriage
The medical term for a miscarriage is "spontaneous abortion" (SAB). A miscarriage (or spontaneous abortion) is a pregnancy that ends without intervention, without surgery or medication, before the 20th week of pregnancy. A "stillbirth" is the death of a fetus after 20 weeks of the pregnancy. A spontaneous abortion (SAB), or miscarriage, is the most common type of pregnancy loss.
Studies show that up to 50% of pregnancies end in miscarriage before the mother realizes she was pregnant and experts estimate that about half of all fertilized eggs die and are miscarried, usually even before the woman knows she is pregnant. Between 10-25% of all clinically recognized pregnancies will end in miscarriage, and most miscarriages occur before the 7th and 12th weeks of pregnancy.
Abortion versus miscarriage
An "abortion" is commonly used to describe the intentional ending of a pregnancy, though medically speaking an abortion could be the unintentional ending of pregnancy (miscarriage or spontaneous abortion) or the intentional ending of pregnancy (induced abortion).
A chemical pregnancy is a pregnancy with a positive pregnancy test but no visible pregnancy on ultrasound, and a chemical pregnancy may account for 50-75% of all miscarriages. A chemical pregnancy occurs when a pregnancy is lost shortly after implantation, resulting in bleeding that occurs around the time of or shortly after her expected period. Unless there was a positive pregnancy test the woman may not realize that she conceived when she experiences a chemical pregnancy.
Miscarriage symptoms and signs
No woman or couple wants to think about the chance of a miscarriage, but a large percentage of pregnancies end before full gestation. Understanding the most common miscarriage symptoms is the best way to be prepared for the chance of miscarriage. Pregnancies are different for every woman and as such, miscarriage symptoms may also be different. There are some women who know from the start that the pregnancy is just “not right” and others who are taken by complete surprise by the miscarriage symptoms.
Lower Abdominal Cramping
Women who are experiencing miscarriage symptoms may feel pain in the lower abdomen similar to menstrual cramping. The pain may stay the same during the miscarriage or could increase in intensity to the point where medical attention is sought. Any form of cramping during pregnancy especially if it's associated with red bleeding should be immediately reported to the obstetrician.
Bleeding More Than Just Spotting
Spotting is common during the first month of pregnancy, but spotting is different from bleeding. Miscarriage symptoms are commonly combined so the cramping may start at the same time as vaginal bleeding. If blood is bright red and flowing like a menstrual cycle, immediately head to the emergency room. Active bleeding from the vaginal during pregnancy is not normal at any time.
Septic Miscarriage Symptoms
Not every miscarriage starts with bleeding and cramping. In some cases, the miscarriage starts an infection in the uterus which leads to vaginal discharge. The vaginal discharge will be thick, possibly yellow or greenish and have a strong smell. Other septic miscarriage symptoms include a fever, lethargy, fatigue and chills. Even if you think the symptoms are associated with the flu or common sinus infection, they can be life threatening is attributed to a septic miscarriage so seek emergency medical attention right away.
Loss of Pregnancy Symptoms
The most difficult miscarriage symptoms to notice are a lapse of pregnancy symptoms. During the first few weeks of pregnancy, breasts will be tender and morning sickness may begin. If these symptoms suddenly stop, they could be considered miscarriage symptoms. Pregnancy symptoms are attributed to estrogen levels in the body and when a miscarriage starts, estrogen levels may quickly return to normal. When this happens, the body no longer “feels” like it is pregnant.
Not all pregnancy losses have symptoms. A missed abortion is a loss of pregnancy without any symptoms, no bleeding or cramps. The diagnosis is usually made by ultrasound when the fetus is found to be non-viable, usually without a heart beat.
Women should not spend the first trimester of pregnancy thinking about miscarriage symptoms, but that does not mean being prepared is wrong. Understanding the common miscarriage symptoms can be life saving.
Most miscarriages occur during the first trimester or before 12 weeks of pregnancy. There can be many confusing terms and moments that accompany a miscarriage, as well as different types of miscarriage, different treatments for each, and different statistics for what your chances are of having one.
The following information gives a broad overview of miscarriage. This information is provided to help you understand what is going on in the body during a miscarriage and be better equipped to cope with the situation. As with most pregnancy complications, remember that the best person you can usually talk to and ask questions of is your doctor.
The different categories and types of miscarriages
Miscarriage is often a process and not a single event. There are many different stages or types of miscarriage. There is also a lot of information to learn about healthy fetal development so that you might get a better idea of what is going on with your pregnancy. Understanding early fetal development and first trimester development can help you to know what things your health care provider is looking for when there is a possible miscarriage occurring.
Most of the time all types of miscarriage are just called miscarriage, but you may hear your health care provider refer to other terms or names of miscarriage such as:
Some degree of early pregnancy uterine bleeding accompanied by cramping or lower backache. The cervix remains closed. This bleeding is often the result of implantation.
Inevitable or Incomplete Miscarriage
Abdominal or back pain accompanied by bleeding with an open cervix. Miscarriage is inevitable when there is a dilation or effacement of the cervix and/or there is rupture of the membranes. Bleeding and cramps may persist if the miscarriage is not complete.
A completed miscarriage is when the embryo or products of conception have emptied out of the uterus. Bleeding should subside quickly, as should any pain or cramping. A completed miscarriage can be confirmed by an ultrasound or by having a surgical curettage performed.
Missed miscarriage or missed abortion
Women can experience a miscarriage without knowing it. A missed miscarriage is when embryonic death has occurred but there is not any expulsion of the embryo. Signs of this would be a loss of pregnancy symptoms and the absence of fetal heart tones found on an ultrasound.
Many people are confused by the word 'abortion' in the term 'missed abortion'. As a result, the term is no longer commonly used. A missed abortion is more frequently referred to today as a delayed or silent miscarriage. This means that the embryo is no longer living (or was never fully formed), though the body has not yet shown signs of miscarriage. It is only classified in this manner, however, if it occurs before the 20th week of pregnancy.
There are a few reasons that a missed abortion may happen. The majority of cases are thought to be due to abnormalities during cell division, though not much is known as to why this happens. A blighted ovum, which is where an egg is fertilized with placenta and no embryo, is another cause for this condition. The other cause is molar pregnancy, which is where the cells in the placenta grow out of control, creating a massive cyst. In both of these cases, the embryo cannot survive.
There are a few ways that a missed abortion (missed miscarriage) will be handled. One is to allow it to run its course and allow the body to naturally expel the embryo or fetus. The other option is to have a D&C procedure to get rid of the tissue.
How to Recognize a Missed Abortion
Since the placenta stays intact, a women will still feel all the signs of pregnancy despite a missed abortion. There are usually no signs of bleeding or cramping that indicate a miscarriage. Some women notice that their pregnancy symptoms start to decrease and they may even have a dark red or brownish spotting. This is known as a silent abortion for. Often, the only way to diagnose this is through regular prenatal exams. The doctor will look for the heartbeat and if this cannot be found, they will be able to diagnose this with an ultrasound. This is one of the many reasons to see your OB/GYN on a regular basis and let them know of any changes you feel.
Recurrent miscarriage (RM) or pregnancy loss (RPL)
Defined as 3 or more consecutive first trimester miscarriages. This can affect 1% of couples trying to conceive.
Recurrent pregnancy loss (RPL), habitual or recurrent abortions or miscarriages are diagnosed when three or more miscarriages occur in a row. About 5% of couples have two miscarriages in a row, and up to 2% have three miscarriages or RPL in a row.
"Primary recurrent pregnancy loss" refers to couples that have never had a live birth, while "secondary RPL" refers to those who have had repetitive losses following a successful pregnancy.
There are many known causes for RPL, however, there is a significant number of couples in whom even after a thorough workup, no specific cause is found.
In a couple with RPL, many doctors usually perform most, if not all, of the following procedures:
- Evaluation of ovarian reserve (LH, FSH, estradiol on CD 3)
- Evaluation for uterine anomalies (Sonogram, hysterosalpingogram)
- Genetic evaluation of both partners (Chromosome karyotyping)
- Hormone evaluation (Progesterone after ovulation, endometrial biopsy)
- Evaluation of autoimmune problems (Lupus screen, ANA, anticardiolipin antibody, factor V Leiden, APPT)
According to the American College of Obstetricians and Gynecologists, cultures for bacteria and viruses, glucose tolerance testing, thyroid tests, antibodies to infectious agents, antithyroid antibodies, paternal human leukocyte antigen status, or maternal antiparental antibodies are not beneficial and, therefore, are not recommended in the evaluation of otherwise normal women with recurrent pregnancy loss.
Also called an anembryonic pregnancy. A fertilized egg implants into the uterine wall, but fetal development never begins. Often there is a gestational sac with or without a yolk sac, but there is an absence of fetal growth.
A fertilized egg implants itself in places other than the uterus, most commonly the fallopian tube. Treatment is needed immediately to stop the development of the implanted egg. If not treated rapidly, this could end in serious maternal complications.
The result of a genetic error during the fertilization process that leads to growth of abnormal tissue within the uterus. Molar pregnancies rarely involve a developing embryo, but often entail the most common symptoms of pregnancy including a missed period, positive pregnancy test and severe nausea.
Why Does a Miscarriage Occur?
A miscarriage, also referred to as a spontaneous abortion, occurs in many pregnancies. Typically, a miscarriage happens before the end of the first trimester, but it can happen at any time in the pregnancy up to 20 weeks. After 20 weeks, the loss of pregnancy is considered a preterm birth.
Studies show that up to 50% of pregnancies end in miscarriage before the mother realizes she was pregnant. Between 10-25% of all clinically recognized pregnancies will end in miscarriage, and most miscarriages occur before the 7th and 12th weeks of pregnancy.
Genetic History, Health and Pregnant Miscarriage
In some cases, women are genetically predisposed to pregnant miscarriage. Women who have multiple miscarriages in pregnancy may fall into this category. The root cause of the pregnant miscarriage may remain unknown or a health related issued may be revealed.
Lower than average HCG or progesterone levels may cause pregnant miscarriage. Progesterone is released by the corpus luteum during ovulation to thicken the uterine wall and prepare the uterus for implantation of the fertilized egg. If the egg is not fertilized, the corpus luteum dies off after 14 days and the elevated progesterone levels return to normal. The menstrual cycle follows shortly after. If a fertilized egg is implanted in the uterus, HCG is released. The HCG keeps the corpus luteum alive and progesterone levels stay high throughout pregnancy.
If there is a health condition that limits HCG or progesterone released, the pregnancy will likely end in a pregnant miscarriage and progesterone and HCG are both needed to carry a pregnancy to term. Even with genetic and health issues, there are times when pregnant miscarriage occurs with no known cause.
What are the odds of a miscarriage
Here are the odds of a miscarriage with different scenarios:
- No increased risk if just one prior miscarriage
- 1 in 4 after 2 consecutive clinical losses
- 1 in 3 after 3 consecutive clinical losses
- 1 in 2 of all (including 'subclinical'=chemical) pregnancies
- 1 in 5 in clinical pregnancies (early pregnancy seen on ultrasound)
- 1 in 10 after 7 weeks with a positive fetal heartbeat
- 1 in 25 after 12 weeks with a positive fetal heartbeat
- 4 in 5 miscarriages happen before 12 weeks
- There is a 2 in 3 risk that a miscarriage is due to chromosome problems
- There is a 4 in 5 risk that a miscarriage is due to chromosome problems if the prior miscarriage was due to chromosome problems
- Less than 1 in 20 chance that a miscarriage is due to a hormone deficiency (for example, progesterone problems)
Predicting a Miscarriage
Successful pregnancy can be predicted with up to 94% accuracy between days 33 and 36 using transvaginal ultrasound to detect 3 markers:
- gestational sac diameter,
- yolk sac size, and
- fetal cardiac activity.
According to new findings presented at the American College of Obstetricians and Gynecologists (ACOG) 57th Annual Clinical Meeting in May 2009. Successful pregnancy can be predicted with up to 94% accuracy between days 33 and 36 after conception using transvaginal ultrasound to detect 3 markers:
- Yolk Sac (2-6 mm over 90% success)
- Gestational Sac (over 12 mm: 92% success)
- Fetal Heartbeat (over 90% success)
The findings were presented by lead author Soyoung Bae, MD, from the Department of Obstetrics/Gynecology, University of Toledo Medical Center in Ohio. Dr. Bae's study was awarded ACOG's third-place prize.
Signs of Miscarriage in Second Trimester
In most cases the signs of miscarriage will appear in the first trimester. The common belief is that if a woman makes it through the first trimester she is safe with a small chance of miscarriage. This does not mean miscarriage will not occur later in pregnancy. Signs of miscarriage in the second trimester may include some of the early signs of miscarriage, but there are a few that are specific to late stage miscarriage.
Early and Late Signs of Miscarriage
When miscarriage occurs during pregnancy, there are some symptoms that present in both early and late miscarriage. These signs of miscarriage include bleeding and cramping. Spotting may occur in the early months of pregnancy, but by the second trimester, the cervix is closed and no spotting should occur. In the latter part of the second trimester, cramping can occur as Braxton Hicks contractions. The uterus must prepare for childbirth so mild cramping is not normally something to worry about, but should be reported to the attending obstetrician.
Other signs of miscarriage that are common in the first and second trimester include lower back pain, pain in the abdomen and pressure in the area of the uterus. These symptoms are similar to those of labor.
Second Trimester Specific Signs of Miscarriage
By the second trimester, the membranes protecting baby are in place. If a woman feels fluid leaking from the vagina or her bag of waters ruptures, this is a clear sign of miscarriage or early labor. It may not be a gush of fluid as is represented in Hollywood movies. Instead, women more commonly feel just a small trickle of fluid similar to urination. If any tissue or grayish material is passed, collect it and immediately take the tissue to the hospital.
Missing Heart Beat - Missed Abortion
If the doctor cannot find a heart beat in the second trimester during a regular doctor’s visit or as part of an emergency visit it could be one of the signs of miscarriage. At times, the heart beat can be difficult to find with a Doppler hand held unit, but an ultrasound will verify the missing heart beat.
Recognizing the signs of miscarriage in the second trimester is important for the health of the pregnant woman. Many of these symptoms will appear after the fetus has stopped growing and thus there is no medical intervention that can be done to save the pregnancy. Doctors will often perform a medical procedure to remove the fetus if the signs of miscarriage lead to a diagnosis of miscarriage.
Pregnancy - Can I get pregnant again after miscarriage?
Yes, many women can conceive after a pregnant miscarriage. About 95% of women who have one pregnant miscarriage will conceive again and give birth. Even women who have more than one pregnant miscarriage have a 75% chance of achieving a full-term pregnancy. In some cases, increasing viability of full-term gestation may require medications to boost HCG or progesterone, but this is not always the case.
Women are most fertile in the time immediately following a pregnant miscarriage, but most obstetricians and gynecologists will suggest waiting until the first normal menstrual cycle has passed before trying to conceive again. In some cases, doctors suggest waiting six months or more before trying to conceive, but this depends on the reasons for the pregnant miscarriage and the common practices of the attending physician.
Pregnant miscarriage is more common than many women understand. Just because a pregnant miscarriage occurs, women are not necessarily less likely to conceive and achieve motherhood. It is best to work with the attending gynecologist or obstetrician to maximize the chance of carrying the fetus to term after a pregnant miscarriage.
Pregnancy after Miscarriage
After a miscarriage, chances of getting pregnant may improve or remain unchanged. The number of miscarriages may decrease chances of getting pregnant over time, but there is also the chance that miscarriages will have no affect on the chances of getting pregnant, just on the chances of carrying the baby to term. The chances of getting pregnant after a miscarriage will greatly depend upon the reasons for the miscarriage(s) in the first place.
How Long Should a Woman Wait After a Miscarriage for Better Chances of Getting Pregnant?
The female body is ready to conceive again immediately after a miscarriage. Hormone levels are at their highest, so infertility is reduced and fertility increased. However, for the sake of the female body and reducing the chance of a second miscarriage, many doctors will suggest waiting at least one regular menstrual cycle to increase chances of getting pregnant and maintaining the pregnancy. Other doctors will suggest waiting up to six months to increase chances of getting pregnant without complications.
What are the Chances of Getting Pregnant After Miscarriage?
The chances of achieving pregnancy after miscarriage are often the same as they are before miscarriage. Women, who try for a second pregnancy, tend to be successful 95% of the time. Women with two or more miscarriages have a success rate of 75% on subsequent tries. Health, illnesses, disease processes and other contributing factors will affect chances of getting pregnant, more than a miscarriage. However, it is important to note that some women are more likely to have miscarriages for unknown reasons. Testing does not always determine a cause for miscarriages.
Chances of getting pregnant after a miscarriage are good, in general. Eating a healthy menu rich in folic acid before attempting a second pregnancy is one of the most important factor increasing chances of getting pregnant. Some experts believe miscarriages are more likely in women with reduced folic acid levels before becoming pregnant. The fetus requires folic acid during the first weeks of development; before a woman even knows she’s pregnant. Taking a prenatal vitamin after having a miscarriage and through the time between the miscarriage and trying again, can boost folic acid levels.