Last week your baby's eyelids were sealed but already sensitive to light. This week, a new sense comes online: hearing. The tiny bones of the inner ear — the smallest bones in the human body — are now sufficiently developed for your baby to detect sound. What they hear is muffled, low-pitched, and filtered through layers of fluid and tissue, but it is real. They can hear your voice. They can hear your heartbeat — the sound that has been constant since the earliest weeks. They can hear your digestion, the traffic outside, music, the sound of your partner talking nearby.

The baby has reached 116mm — an avocado — and has crossed the 100g threshold. The body proportions are now recognisably human: the limbs are in proportion to the torso, the neck is fully extended, and the facial features are distinctly individual. The eyes, still sealed, are pointing forward. The ears are in their final position on the sides of the head. On a scan, the baby looks recognisably like a baby rather than an abstraction.

Eyebrows and eyelashes are beginning to develop this week — fine hairs growing in the follicles above and around the eyes. The unique pattern of these features — like the fingerprints — will be entirely this baby's own. Facial expressions are now more frequent and varied: the foetus frowns, squints, makes what appears to be a smile. These are not conscious expressions; they are the muscles practising the full range of movement they will need.

Quickening — the first time you feel your baby move — is one of the most significant moments in pregnancy. For most first-time parents it happens between weeks 16 and 22. For those who have been pregnant before, it often arrives earlier, around weeks 14–16, because they know what to recognise. Week 16 is the start of the window when quickening commonly arrives for second-time parents, and sometimes, for perceptive first-timers, the very first faint hints.

If you haven't felt anything by week 16, this is not a cause for concern. The timing of first movements varies considerably between pregnancies and between individuals. The position of the placenta plays a role: an anterior placenta (one that sits at the front of the uterus, between the baby and the abdominal wall) acts as a cushion and significantly dampens the sensation of early movement. If you have an anterior placenta — which will have been visible at the 12-week scan — you may not feel movements clearly until weeks 18–22.

The physical experience of week 16 continues the positive direction of recent weeks, with a few specific developments worth naming. The bump, for most people, is now clearly visible — not necessarily to strangers or in winter clothing, but unmistakably present in a mirror or in fitted clothes. This often marks a shift in how the pregnancy is experienced from the outside: people begin to notice, to comment, to offer seats on public transport. The pregnancy enters a new phase of social visibility.

The 16-week appointment typically falls around this week. Blood pressure and urine are checked, the anomaly scan is booked (if not already), and your midwife may offer to listen to the heartbeat with a hand-held Doppler. If they don't offer and you would like to hear it, ask. The first time you hear that rapid, definite rhythm — around 140–160 beats per minute — is its own significant moment.

Week 16 tends to be one of the emotional peaks of the second trimester — not because anything dramatic happens on a fixed schedule, but because of what it contains: possible first movements, audible heartbeat, visible bump, the beginning of the baby being able to hear you. Any one of those things would be significant; together, they can make this week feel like a threshold — the pregnancy becoming, unmistakably, a person.

If quickening hasn't arrived yet, there can be an impatience to week 16 — a watching and waiting that is very different from the anxiety of the first trimester. It is anticipation rather than dread. You know, from the scans, from the heartbeat, that the baby is there and moving. You are simply waiting for the connection to become physical. That waiting is its own form of intimacy.

The anomaly scan — now approaching — may begin to take up more emotional space. Unlike the first trimester scan, which was primarily anticipated with relief, the anomaly scan carries a different weight: it is the detailed structural check, the one that can identify more significant findings, and — for many people — the one where the sex becomes visible. Both the hope and the complexity of that appointment deserve to be acknowledged in advance rather than arrived at unprepared.

Week 16 connects directly to these full topic guides.

Start a movement diary. Not because you need to be monitoring foetal movement this week — formal kick counting is recommended from around week 24 — but because beginning to notice and record the movements now, while they are new and still infrequent, builds the awareness and baseline understanding that becomes important later. Knowing your baby's individual pattern of activity, their busy times and quiet times, makes any future concern easier to assess.

The WiseMama diary is an ideal place for this — a brief note each day of when you noticed movement, what it felt like, and what you were doing. This is not medical monitoring; it is the beginning of paying attention to a specific person with their own rhythms. The notes you write now are also, simply, a record of the beginning of knowing them.

At the 16-week appointment, alongside asking about the anomaly scan booking, raise this:

Knowing whether you have an anterior placenta — and understanding that this typically delays and dampens the sensation of early movement — prevents weeks of unnecessary anxiety when quickening doesn't arrive on the schedule other people suggest. It is a simple question with a specific, useful answer.