At 4 weeks pregnant your period is just late. Implantation was about a week ago and your hCG is now doubling every two to three days. Most women still feel little at this point.
A sensitive urine test is usually positive by now. A blood test additionally shows a number, and two days later whether that number is rising. In week 4 that difference is the whole reason to think about a blood test.
Week 4 counts from the first day of your last period. So you are about two weeks past ovulation, and only a week past implantation.
I think that is worth saying out loud. Almost everything you read now is about a baby the size of a poppy seed. That is no use to you at this moment.
What do you feel at 4 weeks pregnant?
At 4 weeks pregnant most women feel little more than a missed period. Sometimes mild cramps or tender breasts come with it. Nausea arrives on average only after week 5. Having no symptoms in week 4 is normal.
That last point comes from diary research among 341 women. They recorded daily what they felt from their positive test onwards.
Across the whole period from week 2 to 7 after conception, 85 percent had mild cramping. Nausea occurred in 48 percent (PMID 26936888). Those percentages cover the whole period, not week 4 alone.
In a British study nausea began on average on day 39 after the last period (PMID 8373648). That is halfway through week 6. If you are not nauseous in week 4, you are simply on schedule.
What you may notice: your breasts feel heavier and you are tired for no reason. You also urinate slightly more often. They are the same complaints progesterone gives every cycle. This time they just have not gone away.
Can you test positive at 4 weeks?
Yes, at 4 weeks pregnant a sensitive urine test is usually positive. Your hCG has been climbing for a week by then. A test with a high threshold can still be negative. A blood test measures the hormone as a number and has no such threshold.
How much a strip must be able to detect has been measured precisely. Cole and colleagues determined urinary hCG on the day the period failed to arrive. To find 95 percent on that day, a test had to see 12.5 mIU/ml (PMID 14749643).
Of the 18 brands tested, one managed that. A test with a 100 mIU/ml threshold found roughly 16 percent that day. A few days later that figure is far higher, because hCG has doubled in the meantime.
So a negative strip on the first day your period is late says little. Test again with morning urine. Or read our article on a negative pregnancy test while you are pregnant after all.
What is your hCG doing in week 4?
In week 4 your hCG rises fast. It is that rise that tells you something, not the single number.
Barnhart and colleagues followed 287 women with a healthy ongoing pregnancy. They found a median rise of 124 percent per two days (PMID 15229000). The slowest rise still consistent with a healthy pregnancy was 53 percent per two days.
The absolute value varies enormously in week 4. One woman is at 30 IU/l, another at 300, and both can be perfectly pregnant. That is why one number says so little. Two numbers two days apart say so much more.
| Week 4 in numbers | What it means |
|---|---|
| Day 14 to 20 after ovulation | Your period is 0 to 6 days late. Implantation was a week earlier. |
| hCG doubles every 2 to 3 days | Median rise 124 percent per two days; at least 53 percent in a healthy pregnancy (PMID 15229000). |
| Urine test, sensitive (12.5 mIU/ml) | Finds 95 percent of pregnancies on the day your period is due (PMID 14749643). |
| Urine test, 100 mIU/ml threshold | Finds about 16 percent on that day. Far more a few days later. |
| Blood test | Measures hCG as a number in IU/l. A second measurement after two days shows the trend. |
| What the number does not say | Exactly how far along you are, or whether all is well. The scan tells you that later. |
Say you have blood drawn on Monday and your hCG is 120 IU/l. Using Barnhart's figures, you would expect somewhere between 180 and 270 IU/l on Wednesday. That holds for a healthy ongoing pregnancy.
If you are well below that, it is not a diagnosis. It is a reason to discuss it with your midwife.
You can compare a number with what is usual per week in our hCG calculator. How that rise works in detail is in our article on hCG doubling time.
What is the chance of a miscarriage after 4 weeks?
In week 4 the chance of a miscarriage is still relatively high. The earliest losses fall in these weeks. After that the chance drops quickly week by week.
A precise figure for week 4 does not exist. Many early losses are never recognised as a pregnancy.
Wilcox followed 198 pregnancies that were visible only through urinary hCG. Of those pregnancies, 22 percent ended before the woman herself had noticed anything. In total that was 31 percent (PMID 3393170).
The same researchers also looked at late implantation, after day 10. It was linked to a higher chance of early loss (PMID 10362823).
Those are figures about large groups. They say nothing about you. The figures per week are in our article on the chance of miscarriage per week.
What do you arrange in week 4?
In week 4 there is still little to arrange. You register with a midwife, who usually plans a first appointment around week 8 to 10. Advice on folic acid and what to avoid is available from Thuisarts and your midwife.
What you do watch for: severe pain on one side, pain in your shoulder or dizziness. And bleeding that increases. Those are the signs Thuisarts lists for calling the same day.
Mild cramps without bleeding belong to this week and are not among them. More on that in our article on abdominal pain in early pregnancy.
Blood test or wait?
Waiting is a perfectly good choice in week 4. Certainly if you have tested positive and otherwise feel well. A blood test becomes interesting if you want a number, or if your strips contradict each other. Or if you want to see after an earlier miscarriage whether hCG is rising.
My own line on this is simple. One single value rarely reassures. Two values two days apart do, or they give you a timely reason to call.
If you want that number, you can have an hCG blood test done without a referral. Always discuss a result that worries you with your GP or midwife. The overview of all early pregnancy symptoms by day is in our main article.
Sources
- Sapra KJ, Buck Louis GM, Sundaram R, et al. Signs and symptoms associated with early pregnancy loss: findings from a population-based preconception cohort. Hum Reprod. 2016;31(4):887-96. PMID 26936888.
- Gadsby R, Barnie-Adshead AM, Jagger C. A prospective study of nausea and vomiting during pregnancy. Br J Gen Pract. 1993;43(371):245-8. PMID 8373648.
- Cole LA, Khanlian SA, Sutton JM, Davies S, Rayburn WF. Accuracy of home pregnancy tests at the time of missed menses. Am J Obstet Gynecol. 2004;190(1):100-5. PMID 14749643.
- Barnhart KT, Sammel MD, Rinaudo PF, et al. Symptomatic patients with an early viable intrauterine pregnancy: HCG curves redefined. Obstet Gynecol. 2004;104(1):50-5. PMID 15229000.
- Wilcox AJ, Weinberg CR, O'Connor JF, et al. Incidence of early loss of pregnancy. N Engl J Med. 1988;319(4):189-94. PMID 3393170.
- Wilcox AJ, Baird DD, Weinberg CR. Time of implantation of the conceptus and loss of pregnancy. N Engl J Med. 1999;340(23):1796-9. PMID 10362823.
- Thuisarts.nl (Dutch College of General Practitioners). Ik ben zwanger; Ik krijg misschien een miskraam. Accessed 8 September 2026.
Lunara Health provides blood testing and explanation, not diagnosis. Every blood test result includes a professional assessment from a BIG-registered doctor. For treatment decisions, discuss your results with your GP or midwife.
Frequently asked questions
What do you feel at 4 weeks pregnant?
Usually little: a missed period, sometimes mild cramps, tender breasts or tiredness. Nausea begins on average only after week 5. Feeling nothing in week 4 is normal.
What is the chance of a miscarriage after 4 weeks?
The earliest losses fall in these weeks. The chance is still relatively high now and drops week by week afterwards. A precise figure for week 4 does not exist. Group figures say nothing about you.
Can you test positive at 4 weeks?
Yes, a sensitive urine test is usually positive at 4 weeks. A test with a high threshold can still be negative. A blood test measures hCG as a number, without that threshold.
What does your baby look like at 4 weeks?
There is no baby to see yet. There is only a gestational sac that has just implanted, the size of a poppy seed. On a scan there is usually nothing visible yet in week 4.
Is abdominal pain normal at 4 weeks pregnant?
Mild, nagging cramps on both sides are normal and occur in most women. Severe pain on one side, shoulder pain or fainting are not; call the same day.
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Dr. Naimi, BIG-registered physician, oversees the medical standards behind our content and assessments. Read our medical policy
