Why do some women keep having miscarriages? Causes, tests and treatments explained

Ayesha, a 32‑year‑old schoolteacher from Kochi, still remembers the smell of chalk dust on the morning her world shifted. She had just finished her first class when a familiar cramp tightened her abdomen. By afternoon, she was in the hospital — facing her third miscarriage in four years. “I keep doing everything right,” she told me, “but every time I get pregnant, I’m scared to breathe.”

Her story is heartbreakingly common, yet rarely spoken about openly.

Miscarriage is one of the most emotionally difficult experiences a woman can face. When it happens repeatedly, the grief deepens, and so does the fear of trying again. This column aims to gently walk you through why recurrent miscarriage happens, what tests are useful, and what treatments can genuinely help — in clear, practical language.

What exactly is recurrent miscarriage?

A miscarriage is the loss of a pregnancy before 24 weeks. When this happens three or more times, usually in the first three months, it is called recurrent miscarriage. These losses do not need to happen consecutively — many women have healthy pregnancies in between. Recurrent miscarriage affects 1 in 100 women.

In India, people often use the words 'abortion' and 'miscarriage' interchangeably. Medically, abortion refers to an intentional termination of pregnancy, while miscarriage is a spontaneous loss.

Why do miscarriages happen repeatedly?

Most miscarriages — single or recurrent — happen for reasons outside your control. Here are the major contributors:

1. Genetic factors

Half of all miscarriages occur because the embryo develops with abnormal chromosomes. This becomes more common as parents age. In about 6 per cent of couples with recurrent miscarriage, one partner carries a chromosome arrangement that is harmless to them but risky for the embryo.

2. Age

Egg quality declines with age. Risk of miscarriage rises sharply after 35 and even more after 40.

3. Lifestyle factors

Weight matters. A BMI above 25 or below 19 increases miscarriage risk. Smoking, excessive alcohol, and high caffeine intake also raise the chances.

4. Blood clotting problems

A condition called Antiphospholipid Syndrome (APS) can cause recurrent miscarriage and later pregnancy complications. Inherited clotting disorders are less clearly linked, and routine testing is not recommended.

5. Uterine shape

Around 5–6 per cent of women are born with a uterus that has an unusual shape. Among women with recurrent miscarriage, this rises to 13 per cent. A septate uterus or bicornuate uterus can make miscarriage more likely. Fibroids or scar tissue may also play a role depending on their size and location.

6. Hormonal conditions

Poorly controlled diabetes, thyroid abnormalities, PCOS, and abnormal prolactin levels can increase miscarriage risk.

7. Immune and sperm factors

Some theories suggest immune system involvement, but evidence is unclear. Abnormal sperm DNA may contribute, but testing is not routinely offered.

What tests are usually recommended?

Your doctor will aim to identify treatable causes. Investigations may include:

Blood Tests

• APS testing — two positive tests, 12 weeks apart, and at least 6 weeks after a miscarriage.

• Thyroid function and antibodies

• Diabetes screening

• Hormone tests if PCOS or prolactin imbalance is suspected

Genetic testing

If the pregnancy tissue shows chromosomal problems, or if testing wasn’t possible, both partners may be offered genetic tests.

Ultrasound of the uterus

A pelvic scan checks the shape of the uterus. If something unusual is seen, more detailed imaging may be advised.

What treatments can help?

Treatment depends entirely on the cause — and sometimes, no clear cause is found.

Lifestyle changes

• Achieve a healthy weight

• Stop smoking

• Limit caffeine to under 200 mg/day (about two cups of tea or instant coffee)

• Avoid regular or heavy alcohol

These changes alone can significantly improve pregnancy outcomes.

APS treatment

If APS is confirmed, low‑dose aspirin and heparin injections during pregnancy can improve success rates. You will be monitored closely throughout pregnancy.

Inherited clotting disorders

Routine treatment does not improve outcomes, but in selected cases, heparin may be offered depending on your clotting risk.

Genetic counselling

If either partner has a genetic abnormality, counselling helps you understand future risks and options.

Surgery for uterine shape

A uterine septum can be corrected surgically.

For fibroids or other structural issues, the decision depends on size, location, and symptoms.

Hormone treatment

Diabetes and thyroid disease should be well controlled before pregnancy.

Progesterone does not help prevent recurrent miscarriage — unless you have bleeding in early pregnancy, in which case it is recommended.

When no cause is found

This is very common — and surprisingly, the outlook is still good.

Most women with unexplained recurrent miscarriage go on to have a successful pregnancy with supportive care, reassurance scans, and close monitoring.

Emotional well‑being matters

Repeated pregnancy loss can trigger anxiety, depression, and even post‑traumatic stress. Partners often grieve differently, and both may need support. Talking to your doctor, counsellor, or support groups can make a meaningful difference.

Recurrent miscarriage is devastating, but it is not the end of your story.

Most women — including many like Ayesha— eventually carry a healthy pregnancy. With the right investigations, thoughtful care, and emotional support, hope often finds its way back.

The opinions expressed in this article are those of the author and do not purport to reflect the opinions or views of THE WEEK.