How is the due date calculated? Is it dangerous to be pregnant past the due date?

This is an automatically translated article.

The article was professionally consulted by Specialist Doctor II Pham Thi Tuyet Mai - Obstetrician and Gynecologist - Department of Obstetrics and Gynecology - Vinmec Hai Phong International General Hospital.
Pregnancy beyond the expected due date is a case where a pregnant woman is pregnant for more than 40 weeks without any signs of giving birth. Fetal overdue may seem normal, but in fact can greatly affect the health of the fetus.

1. What is your due date?

Your due date is the date your doctor predicts your baby will be born, based on the first day of your last menstrual cycle. The due date is used as a guide to monitor pregnancy and monitor fetal growth. A pregnancy past the due date can lead to serious health problems in the unborn baby.

2. How to calculate due date

Ultrasound is often used to determine due date. Your doctor will predict your due date through ultrasound results and when your last menstrual period occurred. Once determined, your due date will not change throughout your pregnancy no matter how many ultrasounds you have.

3. The fetus is past the expected date of birth

The average gestation period is 280 days, or 40 weeks, calculated from the first day of your last menstrual period. When a pregnancy lasts from 41 to 42 weeks (1 week after the due date) it is called a late pregnancy. For a pregnancy that lasts more than 42 weeks from the first day of the last menstrual period, it is called a preterm pregnancy, or a preterm pregnancy.

4. Causes of overdue fetus

The cause of a preterm pregnancy isn't known, but there are a number of factors that can increase the chances of a baby being past due. These factors include:
First child birth. Bring son son. A previous pregnancy that occurred past the due date. Pregnant women are obese.

5. Is pregnancy past the due date dangerous?

The risk to health for both the mother and the fetus can be increased if the fetus is past due but has not yet been born. However, this problem usually only occurs in a few cases of pregnancy past the due date. Most women who give birth after their due date have normal labor and give birth to healthy babies. Possible risks associated with pregnancy beyond the due date include:
Stillbirth. The baby is too big. Excessive pregnancy. There is stool in the lungs of the fetus, causing the baby to experience severe breathing difficulties after birth. The amount of amniotic fluid decreases, causing the umbilical cord to be compressed and limiting the flow of oxygen to the fetus. Other risks include an increased chance of a woman having to be assisted during a vaginal delivery or having a cesarean section. In addition, the risk of infection and postpartum bleeding is often higher when the pregnancy is past the due date.

6. When should you do a pregnancy test to confirm pregnancy beyond the due date?

When pregnant women are from 40 to 41 weeks pregnant, it is not necessary to have a test. But by the time the fetus is 41 weeks old, the doctor will usually recommend the pregnant woman to take a test to check the status of the pregnancy past the due date. These tests may be done weekly or twice weekly. Sometimes it is necessary to repeat the same tests or do another one. In some cases, your doctor will recommend induction.

7. Tests that need to be done when the fetus is past the due date

7.1. Monitor to monitor fetal response

To check the health of the baby when the pregnancy is past the due date, the doctor will prescribe the use of a monitor to monitor the fetal response and sometimes use the ultrasound method. During the procedure, two belts are placed around the pregnant woman's abdomen to monitor the sensor current. These sensors will measure the fetal heart rate and the frequency of contractions of the uterus.

7.2. Non-stress Test

The Non-stress Test (NST) measures the fetal heart rate over a specific period of time, usually 20 minutes. The results of the Non-stress Test are recorded as either reactive (good outcome) or no response (bad outcome). A bad outcome does not mean the fetus is unhealthy. In case the Non-stress Test results are unresponsive, it is often necessary to perform other tests to have enough information to accurately diagnose the condition of the pregnancy past the due date.

7.3. Biophysics

Biophysics (BPP) is a test that involves fetal heart rate monitoring as well as fetal ultrasound. This test checks the baby's heart rate, breathing, movement and muscle tone, thereby determining the current health status of the fetus. The amount of amniotic fluid will also be assessed by the test results.

7.4. CST . test

The Contraction Stress Test (CST) is used to monitor the response of the fetal heart to uterine contractions. To perform the CST test, the doctor injects the hormone oxytocin into the body through a vein to induce uterine muscle contractions like during childbirth. The test results can help the doctor know how healthy the baby will be when uterine contractions appear during delivery. Results may also be ambiguous or unsatisfactory (when there are not enough uterine contractions needed to produce a meaningful result).

8. What is labor induction?

Induction of labor, also known as induction or induction, may be recommended by your doctor if your baby has reached 41 weeks of gestation or is past the due date. Induction of labor is accomplished using medication or another method. To induce labor, the mother's cervix needs to soften in preparation for childbirth. This is called cervical maturation.

9. Measures to induce labor when the pregnancy is past the due date

When a woman is past her due date, the following methods can be considered by the doctor to induce labor:
Amniotic fluid removal: With this method, the doctor will wear gloves and use his fingers to separate amniotic fluid out of the uterine wall. Breaking the amniotic sac: The doctor will make a small hole in the amniotic sac to break the water, thereby inducing labor. Oxytocin: A medication that induces labor contractions, given intravenously into a pregnant woman's arm. The dosage may be gradually increased over time but must be carefully monitored. Prostaglandin analogs: These are drugs that are placed in the vagina to ripen the cervix. Cervical dilation: Your doctor may place a catheter with a very small balloon attached to the end of your cervix. Then water will be pumped into the ball. Once the balloon is inflated, it applies pressure, which helps the cervix open and labor begins.

10. Risks encountered when inducing labor

Possible risks when performing labor induction for the fetus past the due date, including: Changes in fetal heart rate, infection and too strong uterine contractions. Both mother and baby need to be monitored during induction. On the other hand, there is a risk that induction of labor will not work. At that time, it is necessary to repeat the induction method again. Some cases lead to the risk of having to have a cesarean section or to have a normal delivery.
When the pregnancy is past the due date, the doctor will most likely recommend the use of induction methods. You should discuss possible complications carefully to make sure it's the best decision for your own health and that of your baby.
Vinmec International General Hospital offers a Package Maternity Care Program for pregnant women right from the first months of pregnancy with a full range of antenatal care visits, periodical 3D and 4D ultrasounds and routine tests to ensure that the mother is healthy and the fetus is developing comprehensively.
In particular, the hospital applies non-morphine epidural techniques and nerve anesthesia to help pregnant women reduce pain during labor. During the birth process, the mother will be guided by the midwives on how to push and breathe properly, the baby will be born in just 10-15 minutes. After birth, the baby will be cared for in a sterile room before being returned to the mother.
Pregnant women will rest in a high-class hospital room, designed according to international hotel standards, 1 mother 1 room with full facilities, modern, airy and comfortable like at home. Mothers will be consulted by nutritionists on how to feed the baby before being discharged from the hospital. Postpartum follow-up with both mother and baby with leading Obstetricians and Pediatricians.
For detailed information, please contact the hospitals and clinics of Vinmec health system nationwide.

Please dial HOTLINE for more information or register for an appointment HERE. Download MyVinmec app to make appointments faster and to manage your bookings easily.

Articles refer to Acog.org source