During her third pregnancy, Vanessa Tay started spotting from the first week. “I took everything in my stride as my first two pregnancies were relatively smooth and incident-free,” Tay says.

Although the frequency of her light bleeding increased, Tay brushed it off as a natural side effect of pregnancy. Little did she know that it the precursor to something major.

When she was 16 weeks pregnant, her gynaecologist was concerned that she might be at risk of placenta previa as her placenta was too low. As the pregnancy was still in the early stages, they were hopeful that the organ might re-position itself after several weeks.

However, the situation seemed to deteriorate at every subsequent check-up, until at 20 weeks, Tay was officially diagnosed with placenta previa, followed by major placenta previa four weeks later.

“My bleeding was very severe — it was no longer just spotting but rather, gushes of blood. My doctor ordered me to have complete bed rest at home with extremely painful hormone jabs every week as I was bleeding too much!” Tay recalls.

Scary as it sounds, pregnancy bleeding or spotting is common and does not usually have a sinister connotation. However, in Tay’s case, it was a scary sign that something was wrong. Thankfully, Tay overcame her pregnancy difficulties and went on to deliver a healthy baby boy.

Causes of pregnancy bleeding

One in four pregnant women experience some form of spotting or bleeding during their pregnancy, according to a study by the National Institute of Environmental Health Sciences in the US. For most women, the incidents occur between the fifth and eighth gestational weeks and last less than three days.

One in four pregnant women experience some form of spotting or bleeding during their pregnancy.

What causes pregnancy bleeding at every trimester?

First trimester
First trimester bleeding is vaginal bleeding or spotting that happens in the first 12 weeks of a pregnancy. Most of these bleeds are not significant and the baby is not affected in anyway, explains Associate Professor Tan Thiam Chye, head and senior consultant (inpatient services), Department of Obstetrics and Gynaecology, at KK Women’s and Children’s Hospital.

However, if the bleeding is persistent or painful, it may indicate underlying problems such as a miscarriage or an ectopic pregnancy (the embryo is outside the womb). He cautions, “It is imperative that the expectant woman seeks medical attention, so that the necessary investigations can be performed.”

In an ectopic pregnancy, the embryo implants itself in the fallopian tube after fertilisation. More common when the fallopian tubes are already damaged, it can cause heavy internal bleeding and emergency surgery may be required.

Prof Tan adds, “In most cases of early pregnancy bleeding, the baby is unaffected and the scan shows the presence of the foetal heart. The prognosis is good in such cases of ‘threatened miscarriage’ — the baby will usually be fine. If an expectant woman is experiencing a threatened miscarriage, the doctor would likely prescribe progesterone to stabilise the pregnancy.”

Other possible factors that cause bleeding in the first trimester include:

• Implantation bleeding, which can occur anywhere from six to 12 days after possible conception. The severity differs between women.

• Urinary tract infection or an infection in the pelvic cavity.

• A tender or sensitive cervix Because of extra blood flow to the area, some women may bleed after intercourse or when getting Pap smears or vaginal checks.

Second and third trimesters
Bleeding during this period may pose a health threat to the pregnant woman and unborn foetus. However, Prof Tan notes that in most cases, the cause of the bleeding is unknown and baby is usually well.

“It is important to rule out other more serious conditions such as a low-lying placenta (placenta previa) or premature separation of the placenta from the womb (placental abruption),” adds Prof Tan.

Classically, placenta previa has painless bleeds while the latter condition has painful bleeds, notes Prof Tan.

“Both conditions can be life-threatening to either the expectant woman or the baby and may necessitate a Caesarean-section as a life-saving procedure. It is important to seek prompt medical attention should this symptom occur,” he adds.

Possible causes of bleeding in late pregnancy include:

• Placenta previa, which occurrs in about one in 200 pregnancies. This condition happens when the placenta sits low in the uterus and partially or completely covers the cervix. It is usually detected during the 20-week scan and requires emergency medical attention.

• Placental abruption, which is bleeding that occurs when the placenta detaches from the uterine wall before or during labour. The blood then accumulates between the placenta and uterus. It usually occurs during the last stage of pregnancy and can be life-threatening.

• Premature labour or bleeding when you’re about to deliver. It usually signals that labour is starting. A few days or weeks before labour begins, the mucus plug will pass out with small amounts of mucus and blood (bloody show). If this occurs before the 37th week of pregnancy, you might be experiencing preterm labour. Other signs include abdominal cramps and pressure, lower back pain, contractions and vaginal discharge.S

Seek medical help at once if you experience any abnormal symptoms including vaginal bleeding and strong labour contractions before 37 weeks of pregnancy.

What to do if you start bleeding...

If you experience any bleeding, check with your doctor as it can point to something serious. Record the type of bleeding and discharge and avoid wearing a tampon or having sex.

Prof Tan notes that pregnant women should monitor their health carefully during pregnancy, and go for antenatal check-ups regularly.

Seek medical help at once if you experience any abnormal symptoms including vaginal bleeding and strong labour contractions before 37 weeks of pregnancy, or a sudden decrease in foetal movements, and pain in the abdomen.

“These symptoms may indicate preterm labour, foetal distress, or even placental abruption. As these conditions are critical, the expectant woman would need immediate medical attention,” Prof Tan states.

Photos: iStock

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