Blood tests and Pregnancy go hand in hand. From the initial pregnancy test to childbirth, pregnant mothers must undergo several periodic Blood tests and check-ups. These pregnancy tests (blood tests) are for the benefit of the mother as well as the child.

The second trimester of pregnancy, spanning from weeks 13 to 28, is a crucial period in the journey to motherhood. During this time, both the expectant mother and her developing baby undergo significant changes. Blood tests during this period help detect complications, allowing for necessary interventions.

This article will explore some essential 2nd-trimester blood tests and emphasise their medical significance.

What happens during the second trimester of Pregnancy?

Major developments in the fetus take place during the second trimester. The brain undergoes its most crucial period of growth from the fifth month: eyelids begin to open, eyebrows and lashes start to form, and fingernails start to grow.

Hence, getting a blood test for pregnancy at this stage is crucial. Most prescribed blood tests during this stage check for genetic conditions and track the progress of the development of the foetus.

Here are the various blood tests for pregnancy you will be required to undergo during your second pregnancy trimester

1. Multiple Markers Test

A multiple marker test is a blood test for pregnancy that is always carried out during the pregnancy’s 16th to 18th week. They are used to examine chromosomal disorders and neural tube defects.

The tests are three in number and usually measure specific substances that pass from the foetus to the mother in the body.

The AFP test, also known as alpha-fetoprotein screening, is the test that measures the amount of alpha-fetoprotein in the mother’s blood. When the baby makes alpha-fetoprotein, it passes from the baby to the mother’s blood.

If the AFP is less or more than usual, either of these three things can happen

i. Down’s syndrome: A genetic disorder where the baby has one more copy of chromosome 21, which affects how the baby develops physically and mentally. It is also known as trisomy 21.

Pregnant women should take the AFP test during their second trimester between the 16-22 weeks of pregnancy. However, it is especially recommended for people who are:

• Above 35
• Have a family history of genetic defects
• Have diabetes

ii. The estimated delivery date is wrong: AFP falls and rises in the body based on time in pregnancy. A higher-than-expected or lower-than-normal level of AFP in the body can also mean your previously estimated delivery date is wrong.

iii. You are carrying more than one baby: If you carry more than one baby, you will likely have a higher AFP because each baby will produce its own AFP.

The HCG test and the estriol test also test for the same thing. HCG is also a hormone produced in pregnancy. A higher than typical beta HCG could mean incorrect estimated delivery dates, detection of Down’s syndrome, or multiple gestations. If the HCG is lower than usual, then trisomy 18 is detected.

Estriol is another hormone produced during pregnancy that rises and falls at certain times. Low estriol levels can be associated with the wrong estimated delivery date, Down’s syndrome, and trisomy 18, among other congenital syndromes.

2. Glucose Challenge Test

To check your blood glucose level, take a blood test for pregnancy. The essence of this test is to detect gestational diabetes.

Gestational diabetes symptoms can come from fatigue, excessive hunger, and thirst. If you do not carry out the glucose challenge test, you can easily dismiss it as one of your pregnancy symptoms.

The blood glucose test is in two steps: the glucose challenge test and the Glucose tolerance test.

The glucose challenge test is the first step to test your sugar level after taking food. This test is done within an hour and involves the following procedures.

1. You will be asked to drink a liquid high in glucose.
2. An hour later, your blood sample will be taken to check your blood glucose level.

If the glucose level in your blood is higher than expected, you will be required to take the second test, which is the glucose tolerance test.

Here, your blood sugar levels are measured after a meal. The procedure requires you to follow these guidelines:

1. You should not eat anything when coming for the test.
2. You must drink up to 3 ounces of a glucose solution containing about 100g of sugar.
3. Your blood sugar level post-meal will be tested after the 1st, 2nd, and 3rd hour.

After the results, you will receive an improved diet to help you control your sugar levels.

The second trimester is a crucial time to take blood tests for pregnancy because of the significant developmental changes within that period.

If you are in your second trimester and have yet to carry out your blood tests, book the pregnancy tests with Dr Lal PathLabs after consulting your doctor to ensure your and your baby’s health today!

FAQs

1. What is a multiple marker test?

It is a blood test during the 16th-18th week of pregnancy to check chromosomal disorders and neural tube defects.

2. What is Down’s syndrome?

Down’s syndrome is a genetic disorder caused by an extra copy of chromosome 21, leading to developmental and physical changes.