Chorevia

Day 21 of 280 · 3 weeks

Landing in the womb

Last reviewed · 3 min read · 8 sources · Plain-text version

This week the ball of cells settles into the wall of the womb and the cells that will become the placenta start the supply line. Nothing visible, everything happening.

Size this week
a single cell, then a ball of cells
A couple in their thirties in bed on a Sunday morning, she asleep on her side, he propped on one elbow reading a paperback, soft light through white curtains, a cat at the foot.

Three weeks by the count, one week since conception. This is the week the pregnancy attaches, and the week most of the earliest signs trace back to.

Your baby

After conception, the zygote implants in the uterine wall, and the cluster of cells that forms the placenta supplies the fetus with nutrients and oxygen (NICHD). That is the whole of this week, and it is enough: a ball of cells, which the size line at the top still describes honestly, finding its place and opening a supply line that will run until birth (NICHD).

Implantation is not a single day. It happens about 6 to 12 days after conception (NICHD), which puts it anywhere from the end of last week to the start of next, depending on when the egg and sperm met.

Your body

You may remember nothing from this week, and that is usual. The NICHD's list of early signs starts after implantation: fatigue as early as 1 week after conception, breast tenderness 1 to 2 weeks after, mood swings a few weeks after (NICHD). The one event some women notice is spotting at implantation, which the next two notes cover properly.

From here, your body makes the hormone a pregnancy test looks for; it is formed when the fertilized egg implants, and tomorrow's note is about it (Office on Women's Health). If you later counted back from a positive test and landed near this week, you counted right.

Try today

  1. The implantation timeline

    Time: 5 minutes

    1. On the calendar from day 14, find the end of week 2, around when the egg was released (MedlinePlus).

    2. Count 6 days and 12 days forward from there and bracket them; implantation happens about 6 to 12 days after conception (NICHD).

    3. Inside the bracket, write anything you remember: a day you were unusually tired, a few drops of blood, nothing at all.

    4. Keep it with the first-visit notes. If you ever spot, your provider will want the date and what it looked like (MedlinePlus).

    Make it work:

    "Nothing at all" is a complete answer. Symptoms differ from person to person: every common symptom, a few, or none (NICHD).

Watch for

  • Normal

    light spotting 10 to 14 days after conception, at implantation; if light and brief, it is usually not a concern (MedlinePlus).

    Call your provider right away

    about any bleeding in the first 3 months, which can indicate miscarriage or ectopic pregnancy (MedlinePlus).

  • Normal

    mild cramping, which the NHS lists among the common early symptoms (NHS).

    Go to a provider right away

    for bleeding with pain or cramping, or for belly or pelvic pain; if you cannot reach your provider, go to the emergency room (MedlinePlus).

  • Normal

    being flat-out tired by the afternoon; fatigue can appear as early as 1 week after conception (NICHD).

    Call your provider today

    for dizziness or fainting (CDC).

For you

If you're the partner: there is nothing to see this week, and more happening than in most weeks of your life. A cluster of cells is building the organ that will feed your child for nine months (NICHD). She will not look different, and she may not feel different. Do the quiet thing anyway: ask how she slept, carry the heavy bag, and don't wait for a bump to start.

For both of you, this is also the week that becomes the answer to "when did it start?" Pregnancy usually lasts about 40 weeks counted from the last menstrual period (NICHD), but the attachment, the part that makes it a pregnancy rather than an egg, happened here.

Sources

This guide is general education that summarizes published research and guidance from groups like the American Academy of Pediatrics, the CDC, and the WHO. It isn’t medical advice, and every child develops on their own timeline. Your pediatrician knows your child; if something feels wrong, call them. In an emergency, call 911.

Get each day’s note the morning it applies

Add your due date to a free Chorevia household, and every morning until the birth the day's note arrives in the app and by email: what's forming, what your body is doing, one thing to try, what to watch for, and a word for you.

Create your household