What can prenatal diagnosis tell us and what are the options afterwards

90% Termination Due to Positive New Prenatal Diagnosis

"90% Termination Due to Positive New Prenatal Diagnosis"

You may have heard this phrase before. It’s a shocking statistic, but since the introduction of the new prenatal diagnosis in Japan in 2013, more than 65,000 pregnant women have undergone the test over five years, and data shows that about 90% of the approximately 900 women who were confirmed positive chose to terminate the pregnancy.

What can be determined by the test? How is termination actually performed? Is there care available after an induced abortion? These are questions that many people have.

The following provides a detailed explanation for your reference.

When considering the incidence rate of Down syndrome for a first pregnancy, as shown in the table, the rate increases with age. While male aging also has an impact, the influence of female aging is greater. This is because, as women age, their eggs also age. Eggs are formed during the fetal stage and are ovulated once a month. The longer the eggs remain in the ovaries, the more damage is done to chromosomes that create genetic information, leading to a higher likelihood of chromosomal abnormalities.

What Can Be Determined by the Test

Prenatal tests diagnose whether there are any abnormalities in the fetus. There are genetic tests that examine chromosomal abnormalities and ultrasound tests that examine organ abnormalities. Since 2013, the new prenatal diagnosis (NIPT) has been added, allowing for more accurate testing.

Genetic Testing

Genetic testing is divided into non-diagnostic tests that assess the likelihood of diseases and diagnostic tests that confirm diagnoses. Non-diagnostic tests, which involve minimal sampling or abdominal ultrasound, pose less burden on the mother and have a low risk of miscarriage, whereas diagnostic tests involve inserting a needle directly into the mother, carrying a low risk of miscarriage.

Non-Diagnostic Testing

Ultrasound Testing

Performed around 11–13 weeks of pregnancy, ultrasound testing examines NT (Nuchal Translucency) thickness at the back of the neck, heart rate, and blood flow. NT can be seen in normal fetuses, but an increase in thickness may indicate a risk of Down syndrome or other chromosomal abnormalities.

Additionally, a mid-term ultrasound is performed around 18 weeks of pregnancy, providing more information compared to the initial ultrasound, including the size of the cerebellum and the position of the ears.

Quadruple Test (Maternal Serum Marker Test)

Performed around 15–17 weeks of pregnancy, this test analyzes four components in the pregnant woman’s blood to determine the likelihood of Down syndrome, trisomy 18, and open neural tube defects.

New Prenatal Diagnosis (NIPT)

This test can be performed between 10 and 22 weeks of pregnancy, analyzing the mother’s blood to examine the fetus’s chromosomal abnormalities. The DNA from the placenta mixed with the fetus’s DNA is tested for trisomy 13, trisomy 18, and trisomy 21 (Down syndrome). The criteria for testing include being 35 years or older at the expected delivery date or having a family history of chromosomal abnormalities within two degrees of kinship.

Diagnostic Testing

These tests target all chromosomal abnormalities and are conducted to obtain more accurate information if non-diagnostic tests are positive or if abnormalities are found in the ultrasound. Both tests generally provide definitive results.

Chorionic Villus Sampling

This test can be performed around 10–13 weeks of pregnancy. Depending on the fetus's position, a needle or tube is inserted through the abdomen or vagina to collect chorionic villi, confirming chromosomal abnormalities. Results may take up to three weeks.

Amniocentesis

This test can be performed around 16–17 weeks of pregnancy. A needle is inserted directly into the abdomen to extract amniotic fluid and examine it for chromosomal abnormalities in the fetus. Results may take up to four weeks.

Due to the technical requirements, amniocentesis is more widely available than chorionic villus sampling.

Induced Abortion

If termination is chosen, it must be performed by a doctor designated under the Maternal Health Act (an act to protect the health and life of the mother) before 22 weeks (21 weeks and 6 days) of pregnancy. The methods differ between early pregnancy (before 12 weeks) and mid-pregnancy (12 to 22 weeks).

In the Early Stages

Suction Method

This method involves using a machine to suction the contents out. The procedure is quick, but sterilization takes time to prevent infection.

Curettage Method

This method involves scraping out the contents with a special scissor-like instrument. The simplicity of the equipment and the low risk of infection make this the most commonly used method in Japan.

Both methods take only a few hours, allowing for same-day discharge.

In the Mid-Stages

After 12 weeks, the procedure is treated as an induced stillbirth, where labor is induced similarly to a regular delivery. The procedure involves inducing labor to terminate the pregnancy, requiring 3–5 days of hospitalization for monitoring and ensuring the uterus returns to normal.

Additionally, after 12 weeks of pregnancy, a stillbirth certificate must be submitted to the local government within seven days, and cremation is required.

In most cases, induced abortion is not covered by health insurance and is paid out-of-pocket.

• Under 10 weeks: approximately 130,000–150,000 yen
• 10–11 weeks: approximately 150,000–200,000 yen
• 12–15 weeks: approximately 210,000 yen
• 16–21 weeks: approximately 440,000 yen

In addition, mid-term procedures incur costs for reporting and hospitalization, which vary depending on the gestational week and the size of the fetus.

If Termination is Chosen

Since the implementation of NIPT, the number of people opting for the test has increased each year due to its high accuracy and minimal blood sample requirement. As mentioned earlier, over 60,000 people have undergone the diagnosis since 2013, and approximately 90% of those who tested positive chose to terminate the pregnancy.

Many choose termination due to discrimination and prejudice against disabilities, economic and psychological burdens after birth, and anxiety stemming from a lack of knowledge about Down syndrome.

Women may face emotional and physical burdens from the rapid decisions required and the lack of support from medical institutions not performing termination surgeries, leading to severe emotional distress and prolonged depression.

Nowadays, voices of people in similar situations can be heard through social media. Ultimately, the decision is up to the individual or with their partner, but seeking help from doctors, counselors, and people in similar situations is crucial.

Conclusion

As more facilities offer prenatal diagnosis like NIPT and the accuracy of tests improves, it has become easier to detect fetal abnormalities early. However, some medical institutions may only send results by mail and lack aftercare if abnormalities are found or if termination is chosen. This can leave individuals unsure of where to seek advice, potentially missing the period for termination or suffering from guilt and mental health issues from choosing termination.

Additionally, society still lacks adequate acceptance of people with disabilities.

NIPT is sometimes criticized for encouraging termination, but no one has the right to make decisions for others. Society should aim to create an environment where people can live comfortably regardless of choosing termination or childbirth.

References

• Ritariko Development Navi - Can Down Syndrome Be Diagnosed During Pregnancy?