Being 1 week pregnant covers days 7–13 after the first day of your last period, that is 1+0 to 1+6 weeks. In a regular 28-day cycle conception has not happened yet; with a shorter cycle, ovulation can fall at the end of this week. Pregnancy weeks are counted from the first day of your last period, not from conception. Your body is getting ready to ovulate, and some of your fertile days may fall in this week.
About 0 months and 7 days have passed since the first day of your last period, which counts as the 1st month of pregnancy. In a regular 28-day cycle conception has not happened yet, so at this stage you are not actually pregnant.
In a regular 28-day cycle there is no embryo yet this week. According to ACOG, pregnancy is assumed to start 2 weeks after the first day of your last period, so the roughly 40 weeks of a normal pregnancy include these first 2 weeks when you are not actually pregnant (ACOG, 2026).
Pregnancy is counted this way because the exact day of conception usually cannot be known; even a calculation based on the date of intercourse can be a few days out. Gestational age is therefore measured in weeks from the first day of the last period. According to UpToDate, in a woman with a 28-day cycle, age counted from conception is 14 days less than gestational age, so with this cycle conception has not yet happened at 1 week pregnant.
The window for conception is short: the egg can be fertilised for less than 24 hours after ovulation, while sperm survive no more than 5 days in the female reproductive tract. The fertile window is therefore no more than 6 days per cycle, covering the 5 days before ovulation and the day of ovulation (UpToDate, 2026).
No pregnancy symptoms are expected this week. At this point in your cycle your body is preparing to ovulate, and you may notice it in your vaginal discharge: after your period there is usually no discharge for 3–4 days, then scant, cloudy and sticky discharge for 3–5 days. In the 3–4 days just before, during and just after ovulation, discharge becomes abundant, clear, wet and stretchy.
For women with cycles of 26–32 days, the fertile period has been calculated as days 8 to 19 of the cycle, counting the first day of the period as day 1 (UpToDate, 2026). Being 1 week pregnant overlaps the start of this range. If your cycle is irregular, ovulation can shift; many women do not have 28-day cycles, and ovulation often does not happen on day 14.
If you are planning a pregnancy, this is a good time to prepare:
No pregnancy test or scan is needed this week. According to the NHS, some home pregnancy tests can give a result from about 3.5 weeks of pregnancy.
Organisations differ on when the first antenatal appointment should take place once pregnancy is confirmed:
Your estimated due date is 280 days after the first day of your last period. To work it out by hand, use Naegele's rule: count back 3 months from the first day of your last period and add 7 days. For example, if your last period started on 20 February, your due date is 27 November. The rule assumes a 28-day cycle with conception on day 14 (UpToDate, 2026). You can also use our due date calculator.
Being 1 week pregnant means about 0 months and 7 days since the first day of your last period, which counts as the 1st month of pregnancy. In a regular 28-day cycle conception has not happened yet; with a shorter cycle, ovulation can fall at the end of this week. Because counting starts on the first day of the last period, the first 2 weeks of pregnancy are days when you are not actually pregnant.
Usually not. In a regular 28-day cycle pregnancy has not started at this stage, so no pregnancy symptoms are expected. Even after pregnancy begins, you may have no symptoms at first; a missed period is often the first sign (NHS).
Count the full weeks and extra days from the first day of your last period to today. The result is written as weeks+days; for example, 8+6 means 8 weeks and 6 days. The crown-rump length (CRL) measured on an ultrasound scan in the first trimester is the most accurate way to date a pregnancy; if you are unsure of the date of your last period, or your cycles vary by 7 days or more, the dating is based on it. For a quick answer, use our pregnancy and due date calculator.
Add 280 days to the first day of your last period; by hand, count back 3 months from that date and add 7 days (Naegele's rule). Only about 1 in 20 women give birth on their due date, but the date still sets the timing of tests and helps track your baby's growth (ACOG, 2026).
Last updated: . All sources have been confirmed with their latest versions. This content is for educational purposes and is not a substitute for a doctor's examination.