The hormone primarily responsible for the development of larger breasts is estrogen.
How Estrogen Affects Breast Growth
Estrogen is a key female sex hormone that is produced primarily by the ovaries. Its influence on breast development is significant during puberty and pregnancy. Here's how estrogen works:
- Fat Collection: When the ovaries begin to secrete estrogen, it triggers the accumulation of fat in the breast's connective tissue. This process directly contributes to an increase in breast size.
- Duct System Growth: Alongside fat deposition, estrogen also stimulates the growth of the duct system within the breasts. These ducts are essential for milk production later in life.
Timing of Breast Development
Changes in breast size due to estrogen secretion usually coincide with other developmental milestones during puberty, such as:
- Appearance of pubic hair.
- Growth of armpit hair.
| Hormone | Primary Effect on Breasts |
|---|---|
| Estrogen | Stimulates fat collection and duct growth, leading to breast enlargement |
Conclusion
In summary, estrogen is the primary hormone that causes breasts to enlarge by promoting fat accumulation and duct growth within breast tissue. This typically occurs during puberty alongside other secondary sex characteristics.
