Week 15
Your baby is the size of a navel orange
What's happening this week
Your baby is now the size of a navel orange — about 4 inches (10cm) from crown to rump — and is in a rapid growth phase. Over the next few weeks, your baby will nearly double in length.
Bones are hardening throughout the body, and they're now developed enough to be visible on ultrasound images. If you had a scan this week, you'd see a clear skeletal structure — tiny ribs, a spine, the long bones of the arms and legs. It's one of those ultrasound moments that makes the pregnancy feel astonishingly real.
Your baby's scalp hair pattern is forming this week. The hair follicles are determining where hair will grow on the head, though actual visible hair won't appear for several more weeks. Whether your baby will have a full head of hair at birth or arrive nearly bald is largely determined by genetics.
The legs have now caught up with the arms in proportion, and your baby's movements are becoming more coordinated. Kicks, stretches, and rolls are happening constantly — though at this size, you likely won't feel them for a few more weeks. Some organs are settling into their permanent positions: the ears are migrating from the neck area to the sides of the head, and the eyes are moving from the sides toward the front of the face.
Your baby is also practicing breathing movements — not actual breathing (they get oxygen from the placenta), but rhythmic chest movements that exercise the muscles and develop the lung tissue they'll need at birth. Think of it as rehearsal for the big day.
Your body this week
The second trimester groove is settling in. Many people describe this phase as the most enjoyable part of pregnancy — your energy is back, nausea is usually gone, and you're not yet uncomfortable from the size of your belly. If pregnancy had a sweet spot, this is it.
Your uterus is now large enough that you might feel it if you press gently on your lower abdomen, about two inches below your belly button. Weight gain is typically picking up at about a pound per week from here through the end of pregnancy, though this varies.
You may notice something new this week: a stuffy nose that has nothing to do with a cold. Pregnancy rhinitis affects about 20-30% of pregnant people and is caused by increased blood volume swelling the nasal membranes. Saline nasal spray and a humidifier can help. Avoid decongestants unless your provider specifically approves them.
Some people experience increased vaginal discharge during the second trimester — this is normal as long as it's clear or white and doesn't have a strong odor. If the discharge changes color, smells unusual, or is accompanied by itching, let your provider know.
If you're feeling good and energized, this is an excellent time to tackle things on your to-do list: sign up for a childbirth education class (they fill up), start researching childcare options, and continue gentle exercise. The energy you have now is a gift — use it well, because the third trimester will bring new challenges.
For dads
The golden trimester is your window to get things done together. Your partner is feeling better, you're both adjusting to the reality of the pregnancy, and the due date still feels comfortably far away. This is the ideal time to tackle the big logistical decisions: research childcare (waitlists can be months long), start thinking about the nursery, compare pediatricians, and discuss parental leave plans with your employers. If you haven't already, now is also a good time to review your finances and insurance. Does your health insurance cover delivery? What's your out-of-pocket maximum? Is your partner's parental leave paid, partially paid, or unpaid? These aren't fun conversations, but having answers now prevents stress later.
Your partner may be starting to feel the 'second trimester high' — more energy, less nausea, and a growing excitement about the pregnancy. Match her energy. If she wants to browse baby gear, go with her. If she wants to start thinking about names, engage genuinely. This is the stretch where the emotional bond between the two of you and the idea of your family really solidifies. Show her — through action, not just words — that you're fully in this with her.
Common concerns
Is it normal not to feel the baby move yet at 15 weeks?+
Completely normal. Most first-time parents don't feel fetal movement until weeks 18-22, and some not until week 25. The baby is moving constantly at this stage, but they're still small enough that the movements don't register as sensation yet. Second-time parents often feel movement earlier because they recognize the subtle flutters. Don't worry if you're not feeling anything yet — it's coming.
What is pregnancy rhinitis and how can I treat it?+
Pregnancy rhinitis is nasal congestion caused by increased blood volume and hormonal changes swelling the nasal membranes. It affects 20-30% of pregnant people and can last throughout the pregnancy. Saline nasal spray, a humidifier, and sleeping with your head slightly elevated can all help. Avoid over-the-counter decongestants unless your provider approves them, as some are not recommended during pregnancy.
Is it too early to start thinking about a birth plan?+
It's never too early to start thinking about your preferences, though you don't need a formal plan yet. Consider topics like where you want to deliver, your feelings about pain management, and who you want in the room. A childbirth education class (typically taken around weeks 28-32) will help fill in the details. For now, keep a running list of questions and things to research. A birth plan is a living document that will evolve as your pregnancy progresses.
Should I be concerned about headaches during pregnancy?+
Occasional headaches are common during pregnancy and are often caused by hormonal changes, dehydration, fatigue, or caffeine withdrawal. Most providers consider acetaminophen (Tylenol) safe during pregnancy for occasional use. However, contact your provider if headaches are severe, persistent, or accompanied by vision changes, swelling, or upper abdominal pain — especially in the second half of pregnancy, as these can sometimes indicate preeclampsia.
Product picks for week 15
We may earn a small commission if you purchase through links on this page — at no extra cost to you. Learn more.
Childbirth education class registration
Classes fill up fast — registering now for a class around weeks 28-32 ensures you get a spot in the format you prefer.
Pregnancy memory book
Now that you're feeling good and the bump is growing, it's a perfect time to start documenting this journey with photos and notes.
Saline nasal spray
Pregnancy rhinitis is common and annoying — saline spray is safe, drug-free, and provides relief for stuffy noses.
A quick note: This content is for informational purposes only and is not a substitute for professional medical advice. Always talk to your healthcare provider about any questions or concerns. Learn how we create our content.
Content based on guidance from the American College of Obstetricians and Gynecologists (ACOG), the American Academy of Pediatrics (AAP), Mayo Clinic, and peer-reviewed medical literature. Learn more about how we create our content.