Bleeding during pregnancy can be shocking and worrying for many expectant mothers. Especially in the first weeks of pregnancy, bleeding is not uncommon and, fortunately, usually not a cause for concern. Nevertheless, it should always be taken seriously to rule out more serious causes. In this article, you’ll learn about potential triggers behind bleeding during pregnancy and when you should see your doctor.

What are the causes of bleeding during pregnancy?

The possible causes vary throughout pregnancy, which is why a distinction is made between bleeding in early and late pregnancy. In the first trimester, about one in four women experiences light spotting. The pulling sensation can resemble menstrual cramps, and some women may not even realize they are pregnant. As a result, bleeding in early pregnancy is often mistaken for a period—however, a period cannot occur during pregnancy.

Possible causes in early pregnancy:

Even though it can be scary, bleeding in early pregnancy is often caused by harmless reasons:

• implantation bleeding ( Nidationsblutung ): Between the 7th and 12th day after fertilization, you may notice brief, light red bleeding. At this time, the fertilized egg implants in the uterus and may cause small blood vessel injuries.

• Hormonal change: Some women experience temporary corpus luteum insufficiency at the beginning of pregnancy, meaning the level of the corpus luteum hormone progesterone is too low. As a result, spotting may occur. If hormone levels do not regulate themselves after some time, your doctor may prescribe supplemental progesterone. Corpus luteum insufficiency is one of the most common causes of spotting in early pregnancy and can be treated easily and effectively with progesterone.

• Cervical polyp: This benign growth on the cervix can cause bleeding during (early) pregnancy. A cervical polyp is usually harmless but should be monitored throughout pregnancy.

• Infections of the vagina or cervix: Bleeding caused by infections is usually harmless for the pregnancy and your baby at first. However, you should still have it treated, as it can, in the worst case, lead to premature labor.

• Ektopie: An ectopia is a protrusion of the uterine lining onto the cervix. It is painless, and any bleeding it causes is also harmless. If you have an ectopia, it is usually known before pregnancy. Because the mucous membrane is more richly supplied with blood during pregnancy, the protrusion is often more pronounced.

• Contact bleeding: During pregnancy, your tissues are more richly supplied with blood. During Sexueller Kontakt or vaginal examinations, small blood vessel injuries can therefore occur more easily, which may show up as red or slightly brownish spotting.

• Blasenentzündung oder Hämorrhoiden: Burst Hemorrhoids or a bladder infection can lead to blood in the stool or urine and may sometimes be mistaken for vaginal bleeding. However, they have nothing to do with pregnancy and do not affect it. Nevertheless, you should always consult your doctor if you notice blood in your stool or urine. Bladder infections, in particular, should be treated during pregnancy to prevent a vaginal infection from developing as a result.

In other cases, serious causes can also be behind bleeding in early pregnancy:

• Ectopic pregnancy: The fertilized egg mistakenly implants in the fallopian tube (in the vast majority of cases), in the ovary, in the abdominal cavity, or, in very rare cases, in the cervix instead of the uterus. The surrounding tissue is damaged by the growing embryo, leading to painful, sometimes stabbing spotting. In an ectopic pregnancy, internal bleeding into the abdominal cavity can also occur, which can become extremely dangerous and should be treated medically as quickly as possible.

• Ovarian cyst: If a cyst bursts, surrounding blood vessels can be damaged. This can cause severe internal bleeding, which is not only painful but can also endanger the pregnancy.

• Miscarriage: A Miscarriage can have various causes. Some of them, but not all, can lead to more or less severe bleeding and/or lower abdominal discomfort.

Since bleeding during pregnancy always requires caution and can raise medical suspicion of a (threatened) miscarriage, you should always see a doctor if you notice bleeding.

Possible causes in the second half of pregnancy (after the 20th week of pregnancy):

In the second half of pregnancy, bleeding occurs significantly less frequently than in the first. Even after the 20th week of pregnancy, relatively harmless triggers can be behind the bleeding:

• Contact bleeding: For example, after sexual intercourse or a vaginal examination.

• Blasenentzündung oder Hämorrhoiden: Even in the second half of pregnancy, blood in the urine or stool can be confused with bleeding from the vagina. They do not directly affect the pregnancy, but should still be treated by a doctor in any case. A bladder infection, for example, can lead to an infection if left untreated.

• Cervical polyp: Even later in pregnancy, this harmless growth on the cervix can cause bleeding.

However, bleeding in the second half of pregnancy more often has a serious cause than in the first half:

• Premature placental abruption: If the placenta detaches prematurely from the uterine wall, for example as a result of severe abdominal trauma, it can lead to heavy, painful bleeding. Depending on the extent of the detachment, the baby's supply may no longer be guaranteed, and a cesarean section may be necessary.

• Uterine rupture: A tear in the uterine wall (uterine rupture) also causes painful bleeding and can be life-threatening for both mother and child. However, this does not happen spontaneously; it usually occurs during labor when the uterus is already weakened, often due to previous surgeries.

• Late miscarriage, early or stillbirth: The probability of a Miscarriage decreases significantly over the course of pregnancy. Unfortunately, in rare cases, a miscarriage, preterm birth, or stillbirth can still occur in the second half of pregnancy. These bleeding episodes are accompanied by strong, labor-like pains and loss of amniotic fluid.

• Placenta previa: If the placenta is positioned over the cervix, it can lead to painless, sometimes heavy bleeding and mild contractions, for example after exertion or sexual intercourse. Depending on whether the bleeding persists, a cesarean section may be necessary. In other cases, the expectant mother may be admitted to the hospital for monitoring or advised to rest as much as possible at home.

• Drawing bleeding: This is light bleeding that can indicate an upcoming birth—possibly accompanied by the loss of the mucus plug. After the 37th week of pregnancy, when your baby is considered full term, this bleeding is completely harmless. However, before this time, it can indicate preterm labor.

When should you see a doctor for bleeding?

Most often, the cause of bleeding during pregnancy is not immediately apparent. Therefore, you should seek a medical examination as quickly as possible to determine whether the bleeding is caused by harmless factors or by more serious issues that require treatment. It’s best to contact your doctor or hospital, or go directly to the emergency room in an urgent situation.

How are bleeding episodes treated?

First, the cause of the bleeding will be investigated. Your doctor will ask you about the amount of bleeding, when it occurs, and any pain you may have. During a vaginal (ultrasound) examination, they will check whether the blood is actually coming from the uterus. Next, the placenta will be examined with another ultrasound to assess its location and any possible hematomas. From the second trimester onward, cardiotocography may also be performed to monitor your baby's heartbeat and circulation over a longer period.

If it turns out that harmless causes are triggering the bleeding and your pregnancy is not affected, be sure to give yourself and your body plenty of rest and avoid stress. If your doctor advises it, you should also refrain from sexual activity for the time being.

If more serious reasons are behind the bleeding, further treatment depends on the exact diagnosis. If the bleeding persists or is very heavy, it must be stopped first. This helps prevent the blood loss from compromising your baby’s supply, as well as your own. During an examination at your gynecologist's practice, she/he may arrange immediate transport (lying down) to the nearest hospital, where you and your baby can be closely monitored and further measures can be taken. If a miscarriage is imminent, this may involve administering labor-inhibiting medications and bed rest. In the case of complications in the second half of pregnancy, such as placenta previa, premature uterine rupture, or premature placental abruption, an emergency cesarean section may also be necessary.

More than half of all pregnancies with light bleeding in the first trimester develop normally afterward. However, the likelihood of preterm rupture of membranes and preterm labor is slightly increased after previous bleeding. But don’t let that unsettle you: your doctor will monitor you even more closely if you experience bleeding during pregnancy, so you can hopefully experience and enjoy the rest of your pregnancy without further scares. We wish you all the best!