First and Second Trimester Miscarriage Differences

A young woman looking concerned during a visit to the doctor.
PeopleImages/Getty Images

Miscarriage is the spontaneous loss of a pregnancy before 20 weeks. It occurs in 10% to 20% of all pregnancies, most often before the 13th week of gestation. Many of these miscarriages may happen before women even know they're pregnant. It's estimated that around 10% of known pregnancies are lost in the first trimester. Fewer than 4% of pregnancies miscarry in the second trimester.

Overview

The physical and emotional experience of a miscarriage can vary significantly based on the cause and timing of the loss and other individual factors. Those that occur in very early pregnancy can be quite different from those that happen in the second or third trimester. In some cases, miscarriage can happen almost invisibly, as with so-called missed or silent miscarriages that have no outward symptoms.

The exact risk of miscarriage in the first and second trimesters is challenging to calculate as many miscarriages are not reported and others occur before a woman knows she's pregnant.

Below, we take a look at what typically happens in first-trimester, threatened, and second-trimester miscarriages. Knowing more about causes, signs to look for, and what to expect can help you cope if pregnancy loss happens to you.

First Trimester Miscarriage

Miscarriages happen most often in the first trimester, with many happening before 10 weeks gestation. For the most part, nothing can be done to prevent or stop these pregnancy losses.

Causes

In most first trimester miscarriages, the embryo or fetus stops developing early on, often due to chromosomal or placental problems. In these cases, the woman's body will recognize that the pregnancy is no longer viable and begin to shed the uterine lining. This is the process that causes the tell-tale signs of miscarriage, namely cramping and vaginal bleeding.

Symptoms

In some cases, the bleeding may be light, similar to a regular period. Other women may experience more subtle signs, such as the sudden loss of pregnancy symptoms like morning sickness or breast tenderness. In other instances, weeks may pass before any signs or symptoms appear.

Not all women will have typical miscarriage symptoms or experience them as profoundly.

Confirmation and Treatment

If pregnancy loss occurs during the first trimester, an ultrasound and/or blood tests may be used to confirm the diagnosis. Depending on the timing or cause, the woman may choose to complete the miscarriage naturally or seek assistance to speed up the process in the form of medications or a surgical procedure called dilation and curettage (D&C).

Threatened Miscarriage

In most miscarriages, the baby's heart will have stopped beating before the outward symptoms of miscarriage appear. However, in some cases, vaginal bleeding will occur when the heartbeat is still detectable and the cervix remains closed. This is called a threatened miscarriage.

In many instances, the bleeding will stop and the pregnancy will remain viable. In others, the threatened miscarriage will end in a loss of the pregnancy. There is really no way to predict the outcome. While some doctors will recommend rest and the avoidance of sex, exercise, tampons, and heavy lifting, there is little evidence that these interventions help to preserve the pregnancy.

There’s often little rhyme or reason as to why some threatened miscarriages end in loss and others remain viable to term.

Second Trimester Miscarriage

Early second trimester miscarriages are treated in much the same way as those in the first trimester. However, as the fetus will be further along in its development, the loss will typically be confirmed by the lack of a fetal heartbeat. This is often done via ultrasound.

Common causes of miscarriage in the second term include cervical insufficiency (the premature dilation of the cervix) or preterm labor (also known as premature birth).

Causes

There are multiple reasons for second-trimester miscarriage, including genetic abnormalities in the fetus, drug use (such as cocaine), physical issues with the uterus (such as fibroids), trauma, or maternal medical issues, including diabetes, pre-eclampsia, lupus, or thyroid issues. Sometimes, the cause of pregnancy loss may be uncertain.

With cervical insufficiency (also known as an incompetent cervix), the baby may be born too early to survive. Doctors can sometimes delay delivery with a cervical cerclage (a stitch used to hold the cervix closed). With preterm labor, doctors can sometimes halt the process with anti-contraction medications and bed rest, if the condition is detected early—before miscarriage occurs.

Women who note possible signs of labor should contact their medical practitioner right away.

Pregnancy loss in the second trimester can also be the result of maternal infection (such as bacterial vaginosis or an amniotic infection), congenital conditions (such as uterine structural malformation), uncontrolled chronic illness (including diabetes or hypertension), or placental problems, such as placental abruption or placenta previa.

Symptoms

Symptoms of miscarriage in the second trimester tend to be similar to those in the first trimester—bleeding, cramping, and loss of pregnancy symptoms. These signs may be experienced to a greater magnitude than in the first trimester or may be completely absent.

Some mothers do not notice any signs of pregnancy loss at all until their next prenatal visit when their practitioner fails to detect a fetal heartbeat during a routine ultrasound check. Other women notice the cessation of regular fetal movements.

After 20 Weeks

Pregnancy loss after 20 weeks is considered a stillbirth. In this event, the baby will have died in utero, for any of the above reasons, and the mother will no longer feel any movement. More often than not, the woman will require a D&C procedure to remove the fetal tissue rather than waiting for the process to happen naturally.

A Word From Verywell

Miscarriage can be an emotionally wrenching experience for many women. It can help to know that in most cases, there was no chance of bringing the baby to term and miscarriage is not anyone's fault. If this happens to you, be sure to tend to your emotional wellbeing as well as the physical recovery from pregnancy loss.

Was this page helpful?
Article Sources
Verywell Family uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.