Babies hiccup in the womb surprisingly often. Hiccups actually begin around week 9 of pregnancy, and by 14 weeks, a fetus spends roughly 12% of its time hiccupping. That’s nearly three hours out of every day. Most pregnant people start feeling these hiccups between weeks 21 and 24, and they tend to become more noticeable and frequent during the third trimester.
When Fetal Hiccups Start and Peak
Fetal hiccups are one of the earliest movements a baby makes. They begin during the first trimester, around the ninth week of gestation, well before you can feel any movement at all. During the second trimester, the fetus hiccups frequently, spending a significant chunk of its day doing so. By the third trimester, hiccups typically increase in frequency and become strong enough for you to notice them clearly from the outside.
Most pregnant people first feel fetal hiccups somewhere between 21 and 24 weeks. At that point, you may notice them a few times a day, or just once in a while. The pattern varies widely from one pregnancy to another, and even from day to day. Some people feel their baby hiccup multiple times daily in late pregnancy, while others notice it only occasionally. Both patterns are normal.
What Fetal Hiccups Feel Like
Fetal hiccups feel like small, rhythmic, repetitive jerks or pulses coming from one consistent spot in your belly. They have a steady, predictable tempo, almost like a ticking clock. This is the key difference between hiccups and kicks: kicks and rolls come at irregular intervals, happen in different parts of your belly, and may stop when you shift positions. Hiccups stay rhythmic and localized.
A single episode can last anywhere from a minute to an hour. Early on, they may feel like tiny butterfly-like twitches or muscle spasms. Later in pregnancy, they can be strong enough to see your belly move with each pulse.
Why Babies Hiccup Before Birth
The exact purpose of fetal hiccups is still debated, but the leading theory ties them to early digestive development. Hiccups are controlled by a reflex arc in the brainstem, and their main physical effect is creating a burst of negative pressure inside the chest. In a fetus, this pressure drop may pull amniotic fluid into the developing gut, helping fluid move from the amniotic sac into the baby’s bloodstream and eventually into the mother’s circulation.
This would explain why hiccups are most frequent during the first half of pregnancy, when the digestive system is still forming and the fetus needs to process amniotic fluid. Hiccups may even help regulate amniotic fluid volume: when fluid pressure increases, hiccups could be triggered more frequently to move excess fluid through the system. By the time a baby is born, the diaphragm and surrounding muscles have had months of this reflexive practice.
Are Frequent Hiccups a Concern?
Fetal hiccups are not a sign of distress. You may have come across the idea that frequent hiccups signal umbilical cord compression, but this theory is based on older animal studies that have not held up in human research. A 2017 study compared 150 women who experienced third-trimester stillbirths with 500 women who had healthy pregnancies. About 80% of women in both groups reported feeling fetal hiccups, with no significant difference between the two groups. The results stayed the same after adjusting for age, body mass index, smoking status, and whether hiccups were daily or prolonged.
Clinicians at major medical centers report never encountering data, either in published research or in clinical practice, linking fetal hiccups to poor pregnancy outcomes. In short, even daily hiccups or long episodes are considered normal fetal behavior.
Hiccups and Kick Counts
If you’re doing daily kick counts in the third trimester, hiccups don’t count as movements. Guidelines specifically instruct you to count any fetal movement you can feel except hiccups. This is because hiccups are an involuntary reflex, not an active movement, so they don’t reflect the same kind of neurological activity that kicks, rolls, and nudges do. When tracking your baby’s movement patterns, focus on the non-rhythmic, irregular motions you feel throughout the day.
Changes in the Final Weeks
Some people notice that hiccup episodes become less frequent as their due date approaches. Others feel them right up until delivery. Neither pattern is unusual. What matters more than hiccup frequency is your baby’s overall movement pattern. If you notice a significant change in how often your baby moves (not hiccups, but active kicks and rolls), that’s worth paying attention to. A baby who has been hiccupping several times a day and then stops hiccupping is not, on its own, a red flag.