Your baby this week
Your baby measures about eleven to twelve centimeters — roughly four and a half inches from head to bottom — and weighs around one hundred grams: a small avocado, sitting perfectly in your palm. And this little avocado is getting remarkably capable. The eyes, still sealed shut, have become sensitive to light — shine a bright light on your belly and your baby may actually turn away from it.
The ears are nearly in their final position, and the tiny bones inside them are hardening; over the coming weeks your baby will start picking up muffled sounds — the whoosh of your blood flow, your heartbeat, and eventually, your voice. The arms and legs now move in a coordinated way, bending at elbows and knees, and the hands can find each other — some babies are already practicing thumb-sucking.
The pattern of hair on the scalp is set, the skeleton continues its slow change from rubbery cartilage to bone, and the legs have grown longer than the arms, so your baby finally looks in proportion. At appointments, your doctor can usually find that fast, galloping heartbeat quickly with a handheld Doppler — often the highlight of the visit.
Your body & symptoms: energy returns
For many moms, week sixteen feels like the tide has truly turned. The placenta is fully on duty, hormone levels have steadied, and the nausea and deep fatigue of the first trimester often fade into something much more manageable. Appetites return — sometimes with enthusiasm. Your uterus has grown well up out of the pelvis, and most women now have a visible bump, though its size varies enormously from body to body and pregnancy to pregnancy — all normal.
New sensations to expect: round ligament pain, the famous one — a brief, sharp twinge or ache low on one or both sides of your belly when you stand up quickly, cough, sneeze, or roll over in bed. It passes in seconds or minutes, eases when you rest or change position, and is considered a normal part of pregnancy's remodeling. Also common now: a stuffy nose or even nosebleeds, the beginnings of backache as your center of gravity shifts, skin that's either glowing or breaking out, and the early chapters of heartburn for some.
And the appetite question everyone asks: no, you are not actually "eating for two" — most guidelines suggest only a few hundred extra calories a day in the second trimester, like an extra nourishing snack. Quality beats quantity: protein, iron-rich foods, calcium, and color on the plate. If your brain feels pleasantly foggy some days — the famous "pregnancy brain" — you're in enormous company; sleep, lists, and grace for yourself are the official prescription.
Quickening: the first flutters
Now, the moment everyone asks about: when will you feel your baby move? For most women, those first movements — called "quickening" — arrive somewhere between about sixteen and twenty-five weeks. If this is your first baby, it often lands later in that window, around twenty weeks or beyond; if you've been pregnant before, you may recognize them earlier, because you know what you're listening for.
And "listening" is the right word, because the first flutters don't feel like kicks at all. Women describe them as bubbles popping, a butterfly brushing past, popcorn, or a tiny fish flicking its tail — they're so subtle that most first-time moms realize only in hindsight, "oh, THAT was the baby." A few things affect timing: if your placenta is on the front wall of the uterus, it cushions the movements like a pillow and you may feel them later; most women notice movements most when lying still and quiet, often in the evening. So if you're sixteen weeks and feel nothing: that is completely expected, and it says nothing about how your baby is doing. One sweet note for partners: movements felt from the outside usually come a few weeks after mom feels them from within — not a snub, just the schedule.
Looking ahead: the week-20 anatomy scan
While we're looking ahead, preview your next big appointment: the mid-pregnancy anatomy scan, usually scheduled between about eighteen and twenty-two weeks — most often around week twenty. This is the detailed ultrasound where the sonographer measures your baby's head, heart, spine, stomach, kidneys, and limbs, checks the placenta and the fluid, and confirms how growth is tracking. It's the longest, most thorough look of the pregnancy.
Also on the horizon, just so nothing surprises you: a screening test for gestational diabetes is typically done a bit later, around twenty-four to twenty-eight weeks. Nothing to do about that now — just file it under "future me."