Vaginal bleeding in early pregnancy

Dear ladies, being pregnant is a blessing and an exciting journey.

In general most pregnancy will be an uneventful journey.

However, up to 1 in 5 (20%) pregnant women experience some vaginal spotting or vaginal bleeding during the 1st trimester of pregnancy (also known as early pregnancy).

1st trimester vaginal bleeding is defined as per vaginal bleeding in the first 12 weeks of pregnancy.

In early pregnancy, you may experience some perfectly harmless light vaginal bleeding when the developing embryo implants itself in the wall of your womb (implantation bleeding). This often happens around the time when your 1st period after conception would have been due.

If you are NOT pregnant and having vaginal bleeding, please refer to my other article –abnormal vaginal bleeding.

Causes of vaginal bleeding in early pregnancy:

A) Miscarriage (Spontaneous abortion)

Miscarriage occurs when the pregnancy ends before the 24th week of pregnancy.

Miscarriages are relatively common and up to 1 in 5 pregnancies ends in a miscarriage during the 1st trimester.

Commonly this usually presents with vaginal bleeding and abdominal pain, except for missed miscarriages where the woman can have no symptoms.

Miscarriages can be further categorized as threatened, complete, incomplete or missed and also further classified as sporadic or recurrent (>3 miscarriages).

Threatened miscarriage:

Threatened miscarriages involve a viable foetus (one with a demonstrated heartbeat) but the mother experience vaginal bleeding +/- abdominal pain. About half of these cases may progress into actual miscarriages while the other half can continue on to a normal full term pregnancy.

Incomplete miscarriage:

This is when there are still retained products of conception during the ultrasound scan. The cervical os may be open with products of conception being passed out. The patient would have to undergo a surgical procedure to remove the rest of the products from the womb otherwise a serious infection can occur.

Complete miscarriage:

Patients may present with a history of bleeding, abdominal pain and passage of foetal products. By the time the miscarriage is complete, bleeding and pain usually have subsided. Observation of the aborted foetus with the complete placenta will aid in diagnosis but the woman should have an ultrasound scan done to ensure that the uterus is empty.

Missed miscarriage:

Patients may or may not experience any bleeding or abdominal pain. Usually a missed miscarriage is picked up during ultrasound scanning which identifies an absent foetal heartbeat, indicating foetal demise. This is usually one of the most distressing types of miscarriage as there are usually no warning signs.

Risk factors for miscarriages:

  1. Endocrine disorder

This includes medical conditions such as low progesterone levels, thyroid disease, and poorly controlled diabetes.

  1. Abnormality in the number of chromosomes of the foetus (genetic aneuploidy)

– number and configuration of chromosomes is incompatible with life.

  1. Infection (e.g.: Chlamydia, gonorrhoea, herpes, listeria, mycoplasma, syphilis, toxoplasmosis, and ureaplasma.)
  1. Maternal age: risk of miscarriage increases with age. The greatest increase occurs after 35 years of age.

Other less common risk factors include occupational chemical exposure or radiation exposure.

B) Ectopic pregnancy

Ectopic pregnancy occurs when a fertilised egg implants outside the womb – for instance in the fallopian tube, ovary, etc. This can cause vaginal bleeding but more commonly associated with abdominal pain.

All pregnant women with vaginal bleeding +/- abdominal pain should have an ultrasound scan performed to identify the location of the pregnancy. Early diagnosis of ectopic pregnancy is key to preserving fertility, and preventing complications, which may lead to death.

Risk factors for ectopic pregnancy:

  1. Having a current intrauterine device (IUD)
  2. Previous history of ectopic pregnancy
  3. History of genital tract infection, including pelvic inflammatory disease, Chlamydia, gonorrhoea, etc
  4. Previous history of any fallopian tube surgery
  5. Current pregnancy conceived via In vitro fertilization (IVF)
  6. Smoking


C) Local causes – cervical polyps, cervical cancer

The majority of cervical polyps are non-cancerous and are not uncommon during pregnancy. Most of the time they do not cause any symptoms and you would not know they existed. Occasionally, these polyps can start to bleed on their own or through physical contact such as during sex.

Usually, polyps will get smaller and resolve after delivery and surgery is not needed during pregnancy unless there is constant bleeding or significant symptoms of discomfort.

Rarely, vaginal bleeding can be caused by changes in the cervical cells (pre-cancerous –> cancerous changes). If this is suspected during examination, a pap smear test may be performed. In most cases this should not affect your pregnancy and can be delayed until after the birth.

D) Bleeding after sex

During pregnancy, the cervix softens and the blood supply to the cervix increases. As a result, sexual intercourse can cause light bleeding ranging from a few hours to several days after sex. However, you should always inform your doctor if you experience any bleeding during pregnancy as the episode of bleeding may be unrelated to the cervical changes.

E) Unexplained bleeding (normal pregnancy)

In approximately 1/3 of pregnant women, the cause of vaginal bleeding is unknown. All investigations including ultrasound scans appear normal and the baby appears healthy and growing well. The bleeding may or may not happen again during the pregnancy but if you start to bleed again, it is advisable to see your doctor for an evaluation.

In summary, if you are pregnant and you are experiencing any vaginal bleeding +/- abdominal pain, I would strongly advise you to see a doctor for further evaluation.

Some preconception advice to help reduce the risk of miscarriage or ectopic pregnancy include:

  1. To have a pap smear test performed before getting pregnant as it would make it easier for the doctor attending you to know your updated pap smear status.
  2. Screen for any sexually transmitted infection (STI) especially if you are at risk of any before getting pregnant.
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  1. Dr. I’m having a reddish discharge over a week start on the actual date I suppose to see my mentruation and stopped,after two days it started again very light discharge.It don’t feel pains and it doesn’t smell.I didn’t have any sexual intercourse.I haven’t had abortion before.please could be the cause?

    • Hormonal imbalance. Maybe DUB maybe a persistent CL. Both every benign. If you have every had sex before you should also rule out possible cervical pathologies like HPV infections, pre cancer etc

  2. I started my cycle 2 days late but it wasn’t a regular cycle it started out pink with white stuff in it then after a day and 1/2 almost 2 days of the pink stuff the blood came my cycles are always heavy but this was like a regular cycle well 6 days later and I’m still bleeding its turning into a brown color now with chucks of something in it and its stanky should I go to the hospital I’ve had a miscarriage before and I’m very afraid

    • I can think of 3 possibilities. Yes you are right that this could have been a spontaneous abortion. If this is the case, your body will normalize itself. In rare cases of retained products of conception, you could get infection complications. The second possibility is that you have an infection already. This is suggested by the fact that you noticed a bad smell in the discharge. Third, this could be something hormonal. I think your symptoms definitely merit a trip down to your doctor.

  3. lousomething

    Hi Drs.
    I have recently started nuvaring on July 22 the day of my “period” but this period was nothing like my other ones I have had before. Mine was started out being 7 days long and really heavy well them it started to decrease until it finally got down to two days and still slightly heavy. Well my last period 7/22 was so light I only had to wear panty liner and it lasted four days. Now I have had this ring in since then and now I have been spotting whenever I w wipe and it’s clotty and brown stringy and thick creamy discharge. I took a hpt but it came back neg, so I was just wondering if it is my body adapting to the nuvaring still or something more serious.


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