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At 4 weeks pregnant, your future baby has finally found his home for the next eight months. The blastocyst has arrived from a fallopian tube to your uterus. You can get a positive pregnancy test result at this stage.
By week 5, you should have missed your period, which is one of the most obvious signs you're expecting. Under the influence of hormonal changes, you can feel the first signs of pregnancy: breast swelling, fatigue, headache, and back pain.
Starting from pregnancy week 6, you may experience morning sickness. This is the result of hormonal changes occurring in your body. Malaise, breast swelling, darkening of the nipple areola, and frequent urination can bother you, too. In case of bleeding, you should consult your doctor.
At 7 weeks pregnant, symptoms start kicking in and your uterus almost doubles in size. Be prepared for a possible increase in nausea, fatigue, heartburn, and other pregnancy symptoms. Morning sickness may give a lot of trouble. Try to find some ways to cope with it.
At 8 weeks pregnant, you need to plan your first visit to the gynecologist. The doctor will prescribe the necessary tests and examinations for the first trimester of pregnancy. You may feel the growing discomfort of morning sickness. Try to be patient; it usually lasts until the 14th week only.
At 9 weeks pregnant, your baby is already about 0.6–0.7 in (16–18 mm) and weighs about 0.11 oz (3 g). The tail has disappeared; human features are becoming more distinct. The joints of his/her hands and legs can flex; the nipples and hair follicles are developing. Taste buds are beginning to form on the tongue, as well as primary tooth buds in the gums.
Week 10 of pregnancy is the time when almost all vital organs and tissues of your baby have formed. Now, they are beginning to function and grow rapidly. He or she can swallow amniotic fluid and move their arms and legs. The skin is getting covered with small hair and the fingers have tiny nails. Testes in boys already start to produce testosterone.
At 11 weeks pregnant, your baby has already reached 2 in (5 cm) in size. Now, his/her head is half the length of the body, but in the coming weeks, the body will grow enough to make up for it. The fetus skin is so thin and translucent that through it you can see an extensive network of vessels. Placental vessels are expanding to provide the fetus with necessary nutrients and oxygen.
At 12 weeks pregnant, your baby weighs about 0.49 oz (14 g). His/her vocal cords are forming, and kidneys are starting to produce urine, filling the bladder. Although you cannot feel it yet, you can see the baby during a sonogram screening (ultrasound).
Welcome to the last week of the first trimester! Most early pregnancy symptoms will soon be left behind. At 13 weeks pregnant, your baby is constantly growing. Now, he/she is more than 2.8 in (7 cm) from the top of his/her head to the coccyx.
At 14 weeks pregnant, your baby is developing rapidly. In a while, you will be able to feel them moving and kicking. Your body starts actively gaining weight. This occurs due to an increase in blood and lymph volume.
At 15 weeks pregnant, your baby is actively drawing in amniotic fluid through his/her nose. Very soon you'll start looking pregnant indeed as your uterus has risen from your pelvic region to your lower abdomen. Time to plan pregnancy shopping!
You’re on week 16 of your pregnancy, and things are really starting to gear up! Your tiny baby is not so tiny anymore, and it most definitely looks like a human baby now. By week 16 of your pregnancy, you’re 4 months in. That means you’re nearly halfway there and only have 5 more months to go!
If you’ve been enjoying a relatively subtle pregnancy with very little belly to show for it, that’s probably over now! Your waist will gradually disappear as your uterus moves upwards and out of your pelvis.
If you’ve been astonished by your baby’s rapid growth and weight gain over the last few weeks, by week 18 this will start to level off a little — but there’s still lots of big news in your little one’s early life! At this stage, he or she can yawn, stretch, and even make facial expressions like frowning. The baby’s sense of taste is developing, and taste buds can now distinguish between sweet and bitter.
At 19 weeks pregnant, your rounded belly is very noticeable. The first hair appears on the baby's head, and the brain areas responsible for the senses — tactile, gustatory, olfactory, visual and auditory — are developing rapidly.
Congratulations! You are halfway to meeting your baby. The baby's legs have almost straightened, so from now on, he/she will be measured from head to toe.
As a 21 week pregnant woman, you have crossed the halfway line on your journey to becoming a mother. Your baby is getting bigger. You can now definitely feel her presence as she explores the real estate that you’ve prepared for her.
If you are entering the 22nd week of your pregnancy, without doubts it is getting crowded in there! Your baby is growing and invading your space. And your uterus stretches to about 2 cm (0.8 in) above your belly button to fit your growing baby.
For many women, being 23 weeks pregnant is an exciting time because you may finally be showing your baby bump! Among other things, your baby’s eyes and lips are taking shape. They will begin to gain weight more weight which will eventually fill out their wrinkly skin.
At 24 weeks pregnant, your baby is almost a foot long. You could be experiencing a tingling sensation in your joints, which is known as carpal tunnel syndrome. It is a common condition during pregnancy which occurs due to fluid build-up in your joints which results in compression of the median nerve.
Once you reach week 25 of your pregnancy, you’ll be nearing the end of your second trimester. It can feel like times flies! At 25 weeks pregnant, you’re approximately 5 months and 2 weeks along. Your baby has been growing steadily and even though it’s still not ready, it won’t be long before it comes into the world.
You’re likely to put on between 16 and 22 pounds by now. At one point during this week, your baby will open his or her eyes for the first time. He or she is not yet able to see anything inside of the uterus but will blink closing and opening his or her eyes when falling asleep and waking up.
The 27th week of the pregnancy marks the final two weeks of the second trimester. If your baby is more active at night you might suffer from insomnia and have trouble sleeping. Compensate for the lack of sleep time during the night by napping during the day more when the baby is sleeping.
At 28 weeks you are now entering the third trimester of your pregnancy. At this stage, your baby is pretty well-developed. Her organs, tissues, and nerves continue to grow, but she already has all of the systems necessary for survival outside the uterus. Towards the end of the pregnancy, babies start to recognize familiar sounds and voices.
At 29 weeks pregnant, you're likely to develop varicose veins like 40 percent of expectant moms. It's also a good time to start doing a kick count. Let your doctor or midwife know if you notice that your baby is becoming less active.
At 30 weeks pregnant, you are likely to experience shortness of breath. Your baby is still up high near your rib and is waiting a bit – it is soon expected to drop down into your pelvis.
At 31 weeks pregnant, your breasts can get leaky producing the first baby’s food – colostrum. This is one of the symptoms that your body is getting ready for the big day. You are likely to experience shortness of breath. This week your baby is going through major nerve and brain development.
At 32 weeks pregnant, your body may start flexing its muscles preparing for the big day. Your baby is also preparing for her debut mastering the skills she’ll need to thrive outside your womb: swallowing, breathing, sucking.
At 33 weeks pregnant, you may notice that your baby’s movements are affected by your daily routine. Your belly continues to grow and it’s getting even more troublesome to find a comfortable sitting or sleeping position.
At 34 weeks pregnant, your breasts could start leaking small amounts of yellowish colostrum. Your baby is already the size of a school bag and weighs as a melon. If you’re worried about your safety at work, time to talk to your employer about maternity benefits.
At 35 weeks pregnant, you may know how your baby’s moving in your womb just by looking at your bump. It can you give you some discomfort and make you a bit breathless. At this point, many moms can’t wait for the baby to get here, while others are feeling a bit anxious about giving birth. Both feelings are completely normal!
At 36 weeks pregnant, your baby is sleeping between 60 and 80% of the time. It has finally moved into your pelvic cavity, the pressure on your diaphragm is released, and lightening happens. Your baby can now open its eyes, suck its thumb, breathe, and recognize voices!
Welcome to your 37th week of pregnancy, and congratulations! The baby moves further into the pelvis. It is considered to be ‘at-term’ and can actually arrive any day now. Make sure you are ready for the arrival of a new family member.
At 38 weeks pregnant, you can find yourself spending the whole life peeing. The pressure on your bladder is tremendous. Your baby is a fully functioning little human and your placenta is fully grown.
Welcome to the week 39 of pregnancy! Your baby is full term, meaning that it is fully developed and is only waiting for the right time to make an entrance into the world. Have you prepared everything that is needed to welcome your baby?
At 40 weeks pregnant, you may feel disappointed that your due date has come and gone. Don’t panic and make the last preparations for a new human who’ll soon join the world.
At week 41 of pregnancy, you might be dying out of the desire to give birth and see your baby. But rest assured that plenty of moms-to-be go past their due date and everything turns out just fine.
When a pregnancy lasts for 42 weeks or more it is referred to as a post-term pregnancy. While not many studies exist that prove why some women’s pregnancy lasts for 42 weeks, medical experts believe that factors such as hormones, genetics, and even obesity can be the cause.
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How many weeks pregnant are you?
Typically, pregnancy lasts for about 40 weeks, or 280 days. If you conceive naturally, the estimated due date is usually determined based on the first day of your last period, not from the date of conception. Why is this?
The reason is that most people don’t know exactly when they ovulated or conceived. Someone with a regular 28-day menstrual cycle usually ovulates around day 14.
However, this date isn’t 100-percent accurate, as ovulation can occur earlier or later. This is why a due date is just a rough estimate of the day the baby is likely to arrive.
Due date calculation for IVF pregnancies
In-vitro fertilization (IVF) is the only case in which your health care provider will know exactly when you conceived. Enter this date in the “Date of transfer” field of the calculator.
You can calculate your due date by using different formulas depending on the type of IVF you had. Choose your IVF type in the “Type of transfer” field of the calculator.
This is how Flo’s calculator formulas work based on your IVF type (these formulas are set automatically in the calculator for each option you choose):
- IVF with own eggs (with or without ICSI) — Egg retrieval date + 266 days (or 38 weeks)
- IVF with fresh donor egg cycle (with or without ICSI) — Egg retrieval date + 266 days (or 38 weeks)
- Fresh donor embryo cycle — Egg retrieval date + 266 days (or 38 weeks)
- 3 day FET — Transfer date + 266 days (or 38 weeks) – 3 days (for embryos)*
*Sometimes your embryos’ age is more than 3 days, so it’s important to subtract the exact age of the embryos.
- 5 day FET — Transfer date + 266 days (or 38 weeks) – 5 days (for blastocysts)*
*If the blastocysts’ age is more than 5 days, you need to subtract their exact age.
How accurate are IVF due dates?
Due date calculations may vary regardless of whether you conceived naturally or via IVF. Even with IVF and ultrasound measurements, no due date is a guarantee. It’s just a way to provide a window of time in which you are likely to go into labor.
Try some of Flo's other online tools, including our due date calculator (for non-IVF pregnancies), hCG calculator, our pregnancy test calculator, and our period calculator.