How Does the Size of the Second Child Typically Compare to the First?

Kate Chered
4 min readDec 29, 2023


What is the Reality Behind the Size of the Second Child Compared to the First?

One widespread belief is that the second child is often larger than the first. This is not a myth; it’s a fact supported by medical research. During a second pregnancy, the fetus gains an additional 300–500 grams over the nine months compared to the first pregnancy. This difference is particularly noticeable if the children are of the same gender or the second child is a boy. The reason lies in the mother’s body, which, having experienced pregnancy before, is better prepared and thus can provide more resources for the fetus’s growth and development.

Research from various obstetrics and gynecology studies shows that the maternal body adapts to pregnancy during the first experience, making subsequent pregnancies potentially different in terms of fetal development and maternal health.

When Does a Mother Typically Feel Fetal Movements in Second Pregnancies and How Does It Compare to the First?

Expectant mothers often feel fetal movements earlier in their second pregnancies, typically around the 17–18th week, compared to the 20–22nd week during their first pregnancy. This is not a myth. Many mothers might not recognize these movements in the first pregnancy, mistaking them for gastrointestinal activity. However, during a second pregnancy, they are more familiar with these sensations and can identify fetal movements sooner.

Studies in prenatal care have documented this phenomenon, suggesting that the increased sensitivity of mothers to fetal movements in subsequent pregnancies is due to their prior experience and heightened awareness of pregnancy-related changes.

How Quickly Does the Belly Grow in a Second Pregnancy Compared to the First, and What Are the Underlying Reasons?

It’s true that in a second pregnancy, the belly tends to grow more quickly. This is not because the uterus is larger but because the uterine ligaments have already been stretched during the first pregnancy. Moreover, the abdominal wall is not as taut and elastic in women who have been pregnant before. This allows the uterus to move more freely and tilt forward due to the weight of the growing baby and the surrounding amniotic fluid, making it seem as though the belly is growing faster.

Obstetricians and gynecologists have noted that the shape of the belly can differ significantly between the first and second pregnancies. For instance, a woman with a narrow pelvis may have a more drooping belly during her second pregnancy, whereas the belly might appear sharper and higher in her first pregnancy.

This difference in belly shape and growth rate is also evident before childbirth. It is known that if the belly drops during a first pregnancy, labor could be weeks away, but if it drops in a second pregnancy, labor could be imminent.


How Does the Size of the Second Child Typically Compare to the First?

The second child is often larger than the first. Research indicates an average weight increase of 300–500 grams in second pregnancies. This is especially noticeable if the children are of the same gender or the second child is a boy. The mother’s body is more prepared in subsequent pregnancies, efficiently providing the necessary nutrients for the fetus’s growth.

What is the Earliest Time a Mother Might Feel Fetal Movement in a Second Pregnancy?

In a second pregnancy, mothers generally feel fetal movements earlier, around the 17–18th week, compared to the 20–22nd week in the first pregnancy. With the previous pregnancy experience, mothers are more attuned to these sensations and can distinguish them from other bodily functions like gastrointestinal movements.

When Comparing First and Second Pregnancies, How Does the Rate of Belly Growth Differ?

In a second pregnancy, the belly often grows more quickly. This accelerated growth is attributed to the stretching of the uterine ligaments and a less elastic abdominal wall from the first pregnancy. The uterus, therefore, has more freedom to move and tilt forward, causing a more pronounced belly growth earlier in the pregnancy.

Where Do Differences in Belly Shape Between First and Second Pregnancies Originate?

Differences in belly shape between first and second pregnancies stem from the body’s prior adaptation to pregnancy. Factors like the stretching of uterine ligaments and changes in the abdominal wall’s elasticity contribute to these variations. For example, a woman with a narrow pelvis might have a drooping belly in her second pregnancy, contrasting with a sharper, higher belly in her first.

How Can Mothers Distinguish Between Fetal Movements and Other Bodily Sensations in Subsequent Pregnancies?

In second pregnancies, mothers can distinguish fetal movements more easily due to their previous experience. They become more familiar with the sensation, which helps them differentiate between fetal movements and other bodily activities like digestive processes. This familiarity typically leads to earlier recognition of fetal movements in subsequent pregnanc