Pregnancy Stages of Pregnancy Week by Week Week 16 of Your Pregnancy Your fetus now measures the size of an avocado, and big things are happening to you both during week 16 of pregnancy. Read on to learn more. By Alexandra Frost Updated on March 24, 2023 Share Tweet Pin Email At 16 weeks, you’re nearing the halfway point of your pregnancy. You are in your fourth month—and second trimester. Your body is changing at a fairly rapid pace, and your unborn baby is developing. Their circulatory system is now functioning, pumping more than 25 quarts of blood each day! But you may also be experiencing some aches, pains, and (new or recurring) pregnancy symptoms…or not! The joy of pregnancy is that each and every one is different. Below are some commonly asked questions, doctor’s appointments, and developmental changes you and your unborn baby go through when you are 16 weeks pregnant. Pregnancy Week 16 Quick Facts At 16 weeks, you’re four months pregnantYou have 24 weeks to goYou're in your second trimester Your Unborn Baby's Size at 16 Weeks While you probably won’t “see” your unborn baby for another few weeks—the 20-week anatomy ultrasound usually falls at, you guessed it, 20 weeks—at 16 weeks pregnant, the fetus measures approximately 4.57 inches and weighs about 3.53 ounces. Pregnancy Symptoms Week 16 Though your stomach may have settled—and nausea waned—there are other symptoms some pregnant people experience in week 16, including: Achy back or other jointsIndigestionVaginal dischargeRound ligament pain At week 16, with multiple weeks of the second trimester behind me, I was feeling better than at any point in my pregnancy, except for the pesky headaches that started at week 15. My energy was back, my nausea was low, and I was motivated to have a healthy and happy pregnancy, full of positivity, exercise, rainbows, and butterflies. In retrospect, this is when I should have been planning a nursery, not at 30 weeks. I did have increased back pain as the bump grew, and some other achy joints, making this a great week to pick a pregnancy pillow to get more rest at night. 11 Pregnancy Symptoms You Shouldn't Ignore G. Thomas Ruiz, M.D., OB-GYN at MemorialCare Orange Coast Medical Center, says that low back pain and round ligament pain might cause issues during week 16 of your pregnancy. "The more babies you have, the earlier round ligament pain may start," he says. He recommends Tylenol for pain, Icy Hot on the ligaments such as the back—not the belly—and a maternity belt for support. Developmental Milestones You’re probably wondering what changes are taking place with the fetus this week, and for good reason. Your unborn baby is developing rapidly, and week 16 is no exception. When you are 16 weeks pregnant, the urinary and circulatory systems begin to work—with the latter pumping more than 25 quarts of blood per day. (This will increase to 1,900 quarts by week 40 of pregnancy!) Their eyes and ears are settling in their final positions, and your unborn baby is getting some extra swimming room, in the form of increased amniotic fluid. They are also preparing for a growth spurt in the coming weeks. Prenatal Tests and Doctor's Appointments Between 15 and 20 weeks, a doctor, midwife, or health care provider might order a second trimester screening test to look for abnormalities. You don't have to undergo any of these screenings, but they are recommended. "Everything is optional," Dr. Ruiz explains. When and Why Pregnancy Ultrasounds Are Done At 16 weeks, you might also be heading in for your final visit before the 20-week anatomy scan, if you visit your doctor, midwife, or health care provider every four weeks. You can ask any questions you want ahead of that scan, which looks at the function and presence of all the baby's vital body parts and organs. Common Questions at This Pregnancy Stage What can I expect at my 20-week ultrasound? If you opted out of the second trimester screening test, your provider will look for spinal and brain anomalies during this scan. "By ultrasound, you can see anencephaly, meningomyelocele (commonly known as open spina bifida), and abdominal wall defects,” Dr. Ruiz says. Other conditions may also be apparent. However, in most cases, the 20-week ultrasound, also known as the 20-week anatomy scan, is used to check routine things, like fetal measurements, the heartbeat, and the sex of your unborn baby, if that is something you want to know.Why am I peeing when I sneeze? While it may be embarrassing and even catch you off guard, leaking urine during pregnancy is fairly common, particularly in the second and third trimester—when your expanding uterus can overwhelm your bladder. "If you are completely incontinent, that's one thing, but unfortunately a little leaking is pretty normal during pregnancy,” says Barbara Frank, M.D., a Harvard-affiliated OB-GYN and Attn: Grace medical advisor. The leaking could also be due to a weak pelvic floor, Dr. Frank adds. "If you are leaking in early pregnancy, this may be due to laxity in muscles/pelvic floor that happens quickly when pregnant—especially in a subsequent pregnancy.” The good news is this issue usually resolves itself. In most cases, prenatal urine leaks cease after birth. However, there are things you can do to ease symptoms. "Talk to your doctor so you can learn how to do kegels,” she adds. These perinatal exercises can strengthen your pelvic floor and help prevent leaks. Keep in mind, if the issue continues after birth, pelvic floor therapy is an option and can be very beneficial. Is it safe to visit the dentist while pregnant? For many years, going to the dentist during pregnancy was considered taboo. (An old wives tale deemed it to be risky.) However, visiting the dentist while pregnant is—in most cases—safe. “Preventive dental cleanings and annual exams during pregnancy are not only safe but are recommended,” says the American Pregnancy Association. Crowns, fillings, and other emergency procedures should also be done to reduce the risk of infection. That said, non-emergency and elective procedures should be postponed until after delivery. Things you might consider this week You might have expected your fatigue and nausea to be much better by now, like most pregnant people. But if it's not, you can bring it up to your health care provider. Alyssa Keith, a first time pregnant mom in Philadelphia, says, "I still experienced extreme fatigue and tiredness at 16 weeks. I asked my doctor about whether this was typical in the second trimester, and they recommended drinking a lot of water, exercising, increasing protein in my diet, and taking outdoor walks. Setting aside just a few minutes every day to get outside has made a huge difference in my energy levels." As for nausea, Shannon Tripp, a mom of five in Puerto Rico, experienced gastrointestinal issues through week 16 of pregnancy, longer than most. Eating small and frequent meals and hydrating helped her prolong battle with nausea until it went away. Support You May Need This Week If those achy joints and round ligament pains are getting to you, enlist your partner—if you have one—family members, or friends to support you in remembering to rest, stretch, and take it easy. Trying Dr. Ruiz's recommendations such as Tylenol, Icy Hot, heat and ice, and stretching can make things easier, but so can others pitching in when you aren't feeling up to cooking, clearing, or running an errand. Which Medications Are Safe During Pregnancy? I struggled to ask for support this early in pregnancy, even as joint pain progressed, thinking I "should" have been able to handle it. But with each subsequent pregnancy, symptoms started earlier, and getting some help became a must. I had to step back and realize my limitations before I overdid it, a battle that started each day anew. Luckily, supporters really do want to help, and if you give them a job, they are usually happy to chip in. Head over to week 17 of pregnancy Was this page helpful? Thanks for your feedback! Tell us why! Other Submit