The Two-Week Wait (2WW): What’s baby doing between conception and a positive pregnancy test?

Conception, fertilization, implantation: Our OBGYN explains the biology of early pregnancy and your baby.

The Two-Week Wait (2WW): What’s baby doing between conception and a positive pregnancy test?

You’ve been taking prenatal vitamins and tracking your cycles, and now you’ve decided you’re ready to try to conceive. It’s baby time! You’ve ovulated and had lots of sex, and now you are anxiously waiting two weeks till you can pee on a stick.

But what’s actually going on during that endless-seeming two-week wait?


Around day 14 of the menstrual cycle, the ovary releases an egg that is captured by the fallopian tube. Picture the fallopian tube like a long tube with fingers at the end, which sweep around the ovary to grab the egg when it’s released.


Once it’s in the upper end of the fallopian tube, called the ampulla, the egg meets the sperm for fertilization, usually within 24 hours of being released.


Moving + growing

The fertilized egg then hangs out in the ampulla for about three days before making the three-day trip down the tube to the uterus. These first six days, however, aren’t just about traveling from the ampulla to the uterus. While the egg is making this epic journey, it’s also preparing for implantation by growing and dividing, growing and dividing. This allows the fertilized egg to become two cells, then four, and so on until becoming the 64-cell blastocyst, which is already starting to differentiate into what will become the placenta and what will become baby!


Over the next week, a complex series of events matures the blastocyst into an embryo while implanting it into the uterine lining.

Feeling positive

It is also around this time that the outer layer of cells of the blastocyst start secreting human chorionic gonadotropin, or hCG. This is the hormone you’ve been waiting for, because hCG is what makes your home pregnancy test turn positive. hCG is detectable in the blood as early as eight days after conception, and the level keeps rising until it’s high enough to be picked up in the urine by a home pregnancy test around the time of your missed period, 10 to 14 days after fertilization.

Even though that building anticipation during the 2WW can sometimes border on torture, keep this in mind: The pregnancy hasn’t “stuck” until six to eight days after sperm meets egg, and it takes an extra week for the pregnancy hormone to rise to detectable levels. Hopefully, understanding these two weeks will help you take things one day at a time as your pregnancy begins.

Happy waiting!

References: Human Embryology & Developmental Biology, Fifth Edition. Bruce M. Carlson, MD, PhD. Copyright © 2014 by Saunders, an imprint of Elsevier Inc.

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These are the best bath time products you can get for under $20

These budget-friendly products really make a splash.

With babies and toddlers, bath time is about so much more than washing off: It's an opportunity for fun, sensory play and sweet bonding moments—with the added benefit of a cuddly, clean baby afterward.

Because bathing your baby is part business, part playtime, you're going to want products that can help with both of those activities. After countless bath times, here are the products that our editors think really make a splash. (Better yet, each item is less than $20!)

Comforts Bath Wash & Shampoo

Comforts Baby Wash & Shampoo

Made with oat extract, this bath wash and shampoo combo is designed to leave delicate skin cleansed and nourished. You and your baby will both appreciate the tear-free formula—so you can really focus on the bath time fun.

Munckin Soft Spot Bath Mat

Munchkin slip mat

When your little one is splish-splashing in the bath, help keep them from also sliding around with a soft, anti-slip bath mat. With strong suction cups to keep it in place and extra cushion to make bath time even more comfortable for your little one, this is an essential in our books.

Comforts Baby Lotion

Comforts baby lotion

For most of us, the bath time ritual continues when your baby is out of the tub when you want to moisturize their freshly cleaned skin. We look for lotions that are hypoallergenic, nourishing and designed to protect their skin.

The First Years Stack Up Cups

First year stack cups

When it comes to bath toys, nothing beats the classic set of stackable cups: Sort them by size, practice pouring water, pile them high—your little one will have fun with these every single bath time.

Comforts Baby Oil

Comforts baby oil

For dry skin that needs a little extra TLC, our team loves Comforts' fast-absorbing baby oil aloe vera and vitamin E. Pro tip: When applied right after drying off your baby, the absorption is even more effective.

KidCo Bath Toy Organizer

KidCo Bath Organizer

Between bathing supplies, wash rags, toys and more, the tub sure can get crowded in a hurry. We like that this organizer gives your little one space to play and bathe while still keeping everything you need within reach.

Another great tip? Shopping the Comforts line on to find premium baby products for a fraction of competitors' prices—and follow along on social media to see product releases and news at @comfortsforbaby.

This article was sponsored by The Kroger Co. Thank you for supporting the brands that support Motherly and mamas.

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There is rightfully a lot of emphasis on preparing for the arrival of a new baby. The clothes! The nursery furniture! The gear! But, the thing about a baby registry is, well, your kids will keep on growing. Before you know it, they'll have new needs—and you'll probably have to foot the bill for the products yourself.

Thankfully, you don't have to break the bank when shopping for toddler products. Here are our favorite high-quality, budget-friendly finds to help with everything from meal time to bath time for the toddler set.

Comforts Fruit Crisps Variety Pack

Comforts fruit snacks

If there is one thing to know about toddlers, it is this: They love snacks. Keeping a variety on hand is easy when the pack already comes that way! Plus, we sure do appreciate that freeze-dried fruit is a healthier alternative to fruit snacks.

Comforts Electrolyte Drink

Comforts electrolyte drink

Between running (or toddling!) around all day and potentially developing a pickier palate, many toddlers can use a bit of extra help with replenishing their electrolytes—especially after they've experienced a tummy bug. We suggest keeping an electrolyte drink on hand.

Comforts Training Pants

Comforts training pants

When the time comes to start potty training, it sure helps to have some training pants on hand. If they didn't make it to the potty in time, these can help them learn their body's cues.

Comforts Nite Pants

comforts nite pants

Even when your toddler gets the hang of using the toilet during the day, nighttime training typically takes several months longer than day-time training. In the meantime, nite pants will still help them feel like the growing, big kid they are.

Comforts Baby Lotion

comforts baby lotion

Running, jumping, playing in sand, splashing in water—the daily life of a toddler can definitely irritate their skin! Help put a protective barrier between their delicate skin and the things they come into contact with every day with nourishing lotion.

Another great tip? Shopping the Comforts line on to find premium baby products for a fraction of competitors' prices—and follow along on social media to see product releases and news at @comfortsforbaby.

This article was sponsored by The Kroger Co. Thank you for supporting the brands that support Motherly and mamas.

Our Partners

It's science: Why your baby stops crying when you stand up

A fascinating study explains why.

When your baby is crying, it feels nearly instinctual to stand up to rock, sway and soothe them. That's because standing up to calm babies is instinctual—driven by centuries of positive feedback from calmed babies, researchers have found.

"Infants under 6 months of age carried by a walking mother immediately stopped voluntary movement and crying and exhibited a rapid heart rate decrease, compared with holding by a sitting mother," say authors of a 2013 study published in Current Biology.

Even more striking: This coordinated set of actions—the mother standing and the baby calming—is observed in other mammal species, too. Using pharmacologic and genetic interventions with mice, the authors say, "We identified strikingly similar responses in mouse pups as defined by immobility and diminished ultrasonic vocalizations and heart rate."

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