4 Factors That Can Affect Your Baby Bump Size

baby bump size

Baby Bump: The Size May Vary

An obvious reason for a big bump is that there is more than one baby thriving in the womb. Other reasons that determine the size of the bump include the amount of fluid in the amniotic sac, and the position of the baby. Many women anxious to compare their bumps with their friends. But, there is no such thing as a right size. No one can judge the size of the baby by simply looking at your belly.

1. Height And Weight

height-and-weight:baby bump size


The height of the mother can determine the space baby gets to grow in. If you are taller, the uterus will grow more upward than outward, making your belly look smaller. The contrary applies to women who are shorter.

2. Position Of The Baby

baby-position: factors affecting bump size


The position of the baby can also determine the belly size and shape. If you have a perfect basketball-round belly, your baby is in the anterior position, which means its head is towards the mother’s front, and its eyes are facing towards her back. This is an ideal position for normal birth. The baby can also be in the posterior position – the back of its head is towards the mother’s back, but the baby is not facing upwards towards her front. The bump may not be as round in this case, and may have a slight dip below the belly button.

3. Previous Pregnancies

previous-pregnancy: baby bump size


Even previous pregnancies can alter the shape of your baby bump. Your muscles become flexible after your first pregnancy, and don’t regain their earlier tone. Due to this, you bump may be visible much earlier, and appears much bigger during the second pregnancy.

4. Amount Of Amniotic Fluid

amniotic-fluid: Size of baby bump


In the first 20 weeks, your body produces most of the amniotic fluid. In the later stages, your baby produces the larger part if it, mainly through lung secretions and urine output. So, your belly size might vary depending upon the fluid produced by the baby.

Low Amniotic Fluid And Baby Size



If your bump size appears to be smaller, the reason can be lower amniotic fluid levels – a condition called oligohydramnios. The possible causes can be:

  • The Water Is Broken: Your water may slowly leak or break out, because of a tear in the amniotic sac. If your water is broken consult your doctor immediately, as there can be a risk of infection if you don’t go into labor.
  • A Problem With The Placenta: This could be if your placenta isn’t supplying sufficient amounts of blood, and nutrients to the baby.
  • Medication Taken By The Mother: Some drugs can lower the amniotic fluid levels. These could be given for treatment of high blood pressure, or reduce inflammation and fever.
  • Baby Has A Health Problem: In certain conditions, the baby may not be producing or passing enough urine. There can be a problem with its kidneys or heart. Such conditions are usually picked up on the ultrasound scan, and demand special fetal treatment and care.
  • One Of The Identical Twins Is Not Getting Required Nourishment: This happens if the twins share a placenta, and one baby gets more blood than the other. It could lead to one of them having extra fluid and the other insufficiently.

High Amniotic Fluid And Baby Size

high-amniotic-fluid: factors affecting baby bump size


The condition of having too much amniotic fluid is called polyhydramnios or hydramnios. This is often seen in identical twins, gestational diabetes, and sometimes congenital abnormalities.

  • Gestational Diabetes

This happens when your pancreas doesn’t produce enough insulin to break the sugar in your body. High levels of sugar in the mother’s body can cross the placenta, which is then taken up by the baby to convert into fat, muscles, and enlarged organs.


Healthy babies come in all shapes and sizes. You can have a bump resembling a beautiful and neat watermelon, or big enough to comfortably place your snacks-tub over it. Unless you have one of the above medical conditions, the size of your belly shouldn’t really matter.