Why do they say 9 months when it's 40 weeks?

People say pregnancy is 9 months because it's a simple, rounded estimate, but it's actually closer to 10 months (40 weeks) when calculated from the last menstrual period (LMP) due to months having more than 4 weeks, leading to about 9 months plus a few weeks. The medical standard of 40 weeks (280 days) from LMP is used for precision, but the common "9 months" shortcut arises from dividing 40 weeks by an average of 4 weeks per month, which doesn't account for the extra days in most months, making the total duration closer to 10 calendar months.

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When are you technically 9 months pregnant?

You might still be wondering how many weeks nine months pregnant is. There is no simple answer, as the weeks of pregnancy don't fit evenly within nine distinct months. This final month could start anywhere from 33 weeks to 36 weeks and "end" somewhere around 40 weeks with the birth of your baby.

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Why does it take 9 months for a baby to be born?

The prevailing explanation for why pregnancy doesn't last that long boils down to something called the "obstetrical dilemma." Humans walk upright. And the size and shape of our pelvises are constrained by our bipedal way of getting around in the world. If they got much bigger, mothers wouldn't walk as well.

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How many months am I if I'm 40 weeks pregnant?

A full-term pregnancy is about 40 weeks (or a little over 9 months) long.

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Why is pregnancy counted in weeks not months?

According to the NHS the average length of a full-term pregnancy is 280 days or 40 days. The reason it is counted in weeks and days, not months, is because it is a more precise way of ascertaining where a woman is in her pregnancy rather than calculating it in calendar months, which have varying lengths (i.e..

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Why do they say 9 months when it's 40 weeks?

44 related questions found

Why is pregnancy 40 weeks but only 9 months?

The rationale for this is that, from the medical viewpoint, gestational age is counted from the date of the last menstrual period (LMP). This adds about 2 more weeks to the total length of pregnancy, since ovulation and fertilization occur two weeks after the LMP.

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Is 31weeks 8 months pregnant?

At 31 weeks pregnant, you're still around seven months pregnant. You're getting closer to meeting baby each day! In fact, at 31 weeks pregnant, you only have around 60 days left before the big day!

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Is 40 or 41 weeks full term?

ACOG and SMFM use these definitions to describe term pregnancies: Early term: Your baby is born between 37 weeks, 0 days and 38 weeks, 6 days. Full term: Your baby is born between 39 weeks, 0 days and 40 weeks, 6 days. Late term: Your baby is born between 41 weeks, 0 days and 41 weeks, 6 days.

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What happens if you don't go into labor at 40 weeks?

If the pregnant woman does not go into labor within a week from the due date, the doctor may recommend the mother to undergo monitoring tests to record the fetal heart rate and a 40-week ultrasound to observe the baby's movements, ensuring that the baby is receiving enough oxygen and that the nervous system is still ...

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How many kg should a baby weigh at 40 weeks pregnant?

Babies usually weigh an average of 3 to 4 kg by this late stage of pregnancy.

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What makes a baby come early?

Babies born before 37 weeks are premature. A premature birth is more likely to happen when a mother has a health problem — like diabetes — or does harmful things during her pregnancy, like smoke or drink.

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Is 36 weeks exactly 9 months?

You're officially 9 months pregnant at 36 weeks, but you still have roughly four more weeks until you'll meet baby.

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What is the longest pregnancy ever recorded?

But other doctors at Los Angeles' Methodist Hospital found it incredible that Mrs. Hunter had been pregnant 375 days (instead of the normal 280) before her baby was born there last week; 375 days would be the longest pregnancy on record, topping the runner-up by about 58 days. The evidence as presented by Dr.

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Is the baby fully developed at 36 weeks?

At 36 weeks, a baby's body is nearly fully developed, and they are usually ready to survive outside the womb. At week 34, many of the baby's bodily systems are not yet fully mature, especially the lungs. The lungs do not reach full development until around 36 weeks.

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What is considered a high-risk pregnancy?

For example, women who have chronic health problems, such as high blood pressure or diabetes, who become pregnant may be considered to have high-risk pregnancies—even if the condition is well controlled. Other factors, such as infections, injuries, and disorders of pregnancy, can also put a pregnancy at high risk.

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What if my pregnancy lasts longer than 40 weeks?

If your pregnancy lasts more than 42 weeks, it is called post-term (past due). This happens in a small number of pregnancies. While there are some risks in a post-term pregnancy, most post-term babies are born healthy. Your health care provider can do special tests to check on the health of your baby.

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What is the quickest way to go into labor at 40 weeks?

How to induce labor: Natural ways to start the process

  • Exercise. Walking and exercise often make it to the top of the list of things to try. ...
  • Spicy foods. ...
  • Sexual intercourse. ...
  • Acupuncture and acupressure. ...
  • Nipple stimulation to induce labor – discouraged. ...
  • Castor oil to induce labor – highly discouraged and potentially dangerous.

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What causes the baby to be overdue?

It is usually not known why a baby is overdue. Sometimes it is because of a genetic predisposition (hereditary). Women who have already had a baby that came much later than their due date are more likely to have an overdue baby in future pregnancies.

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What are silent labor signs?

The signs of labor will vary for every pregnant person; some symptoms may be more subtle than others. Some early signs of early labor include nausea, vomiting, diarrhea, increased bowel movements, lower back pain, cervical dilation and effacement and the loss of the mucus plug.

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Why don't they let you go past 41 weeks?

Going past your due date

But once you reach 41 weeks, the risks, whilst still very small, do start to increase. These include: needing a caesarean birth. your baby needing care in a neonatal unit.

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Do most babies come at 39 or 40 weeks?

25% gave birth by 39 weeks and 5 days after the LMP. 50% gave birth by 40 weeks and 5 days after the LMP. 75% gave birth by 41 weeks and 2 days after the LMP. 90% gave birth by 44 weeks and zero days after the LMP.

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Why is 37 weeks no longer considered full term?

“Your baby's lungs, liver and brain go through a crucial period of growth between 37 weeks and 39 weeks of pregnancy. Waiting until 39 weeks, now called 'full term pregnancy,' gives your baby the best possible chance for a healthy start in life.”

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Which week does 9 month start?

Weeks 34-36: At the end of week 36, you will be nine months pregnant. Your baby will go through some final development, such as skin smoothing out and fully growing out their nails.

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Should my breasts be leaking at 32 weeks?

The first milk your breasts produce is called colostrum. This is produced from about sixteen weeks of pregnancy onwards and your breasts may leak colostrum from 28 weeks. This is not an indicator of whether there will be enough for the baby. The amount of colostrum will vary from woman to woman.

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Can I still sleep on my back at 31 weeks?

Research has shown that in the third trimester (after 28 weeks of pregnancy) going to sleep on your back increases your risk of stillbirth. As the link has now been shown in 6 separate research trials, our advice is to go to sleep on your side in the third trimester because it is safer for your baby.

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