The Playbook

4 Weeks Pregnant: The Positive Test, a Dad's First Moves

By the Guide to Fatherhood editorial team. Last reviewed . 2 min read.

Checked against guidance from organizations like the AAP, CDC, ACOG and NHS (linked below). This is general information, not medical advice. Read our medical disclaimer.

Trimester1
Sizea poppy seed
Lengthabout 1 mm

The embryo has implanted in the uterine lining and is forming layers of cells that will become every organ. The placenta and amniotic sac are starting to develop.

Your to-do list this week

  • React to the news with your whole face. Whatever you're feeling, lead with 'I'm with you.' Process the rest later.
  • Help her call her doctor or midwife to book the first prenatal visit, which is often around 8 weeks, sometimes earlier.
  • Take over the cat litter permanently. Cat feces can carry toxoplasmosis, which is risky in pregnancy.
  • Put the due date into the tracker and save it to your phone's home screen.
  • Start a shared notes doc for questions for the first appointment.
A conversation to have this week

"Who do you want to tell, and when?" Some couples tell parents right away; others wait until after the first ultrasound or the end of the first trimester. There's no wrong answer, but there should be a shared one.

It’s positive. Now what?

First, breathe. Whatever you feel right now, whether that’s joy, terror, or both in the same five minutes, is normal. Lead with warmth: “We’re doing this together.” The spreadsheet can wait until tomorrow.

Second, remember that she’s been carrying this news (and probably three more tests) for some time before telling you. Ask how she’s feeling about it, and actually listen.

The baby this week

At four weeks, the embryo is about the size of a poppy seed. It has finished implanting into the uterine lining and is organizing into layers of cells that will go on to form the brain, heart, gut, skin, and everything else (Mayo Clinic). The amniotic sac and the early placenta are forming too (NHS).

How she may be feeling

Possibly no different at all. Or: tired in a way she’s never been tired, sore breasts, peeing more often, a little crampy. Nausea often starts in the next couple of weeks. All normal.

Your first practical moves

  1. Book the first prenatal visit. Call her doctor or midwife’s office, or a new one if she doesn’t have one. They’ll ask for the first day of her last period and tell you when to come in.
  2. Take the cat litter. The CDC advises pregnant people to avoid changing cat litter if possible because of toxoplasmosis. That job is yours now. Wear gloves and wash your hands.
  3. Start the questions doc. First appointments are fast. Write down what you want to ask: medications she takes, family medical history from both sides, symptoms that mean “call us.”
  4. Check insurance. Find out whether her provider and the hospital where they deliver are in-network.

Telling people

It’s your partner’s body and largely her call, but it should be a shared plan. Many couples wait until after a first ultrasound or the end of the first trimester; others want their closest people to know right away so they have support either way. Talk it through this week, and then guard the secret like it’s your job, because it is.

Frequently asked questions

When is the first prenatal appointment?

Many practices schedule the first visit around 8 weeks, though some see you earlier, especially if there are health conditions, previous complications, or symptoms like bleeding or pain. Call the practice as soon as the test is positive; they will tell you when to come in.

Can I still have a beer around her?

There's no medical reason you can't, but plenty of dads choose to cut back or join her in going without. It's a small, visible way to be on the same team.

Sources

  1. Week 4: Your baby and your body, NHS
  2. Fetal development: The first trimester, Mayo Clinic
  3. Toxoplasmosis: Pregnant women, Centers for Disease Control and Prevention

We link to the original source for every medical and safety claim. Guidance changes; if a source has been updated since our last review, the source wins. How we research.