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Physical Development In Girls: What To Expect

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Physical Development in Girls:  What to Expect

Breast Development (Thelarche)

The first visible evidence of puberty in girls is a nickel-sized lump under one or both nipples. Breast buds, as these are called, typically occur around age nine or ten, although they may occur much earlier, or somewhat later. In a study of seventeen thousand girls, it was concluded that girls do not need to be evaluated for precocious puberty unless they are Caucasian girls showing breast development before age seven or African American girls with breast development before age six. It is not known why, but in the United States, African American girls generally enter puberty a year before Caucasian girls; they also have nearly a year’s head start when it comes to menstruation. No similar pattern has been found among boys.

Regardless of a girl’s age, her parents are often unprepared for the emergence of breast buds, and may be particularly concerned because at the onset of puberty, one breast often appears before the other. According to Dr. Suzanne Boulter, a pediatrician and adolescent-medicine specialist in Concord, New Hampshire, “many mistake them for a cyst, a tumor or an abscess.” The girl herself may worry that something is wrong, especially since the knob of tissue can feel tender and sore, and make it uncomfortable for her to sleep on her stomach. Parents should stress that these unfamiliar sensations are normal.

What appear to be burgeoning breasts in heavyset prepubescent girls are often nothing more than deposits of fatty tissue. True breast buds are firm to the touch.

Q: “My daughter just started developing breasts. Should she be wearing a training bra?”

A: There’s no need for one right now, as long as she’s comfortable. But given the sensitivity of early breast tissue, some girls find it more comfortable to wear a soft, gently supportive undergarment like an undershirt or sports bra. Let her decide. Girls’ feelings about their first bra are decidedly mixed. Some are thrilled to take this early step toward womanhood, but others are mortified by the thought of wearing a bra to school.

Q: “Why is one of my breasts bigger than the other?”

A: In the early stages of puberty, it is not unusual for one breast to be noticeably larger than the other. Young girls aren’t always told this, however, leading many to worry that they’re going to be “lopsided” forever. Breast size usually evens out within a year or so, although most adult women’s breasts are slightly different in size. Unless the difference is significant, padding the bra cup for the smaller side is frequently considered a satisfactory solution. However, sometimes the difference in size is very pronounced. This condition, asymmetrical breasts, is more common than you might think. The situation occasionally resolves itself, but if not, some young women may want to pursue plastic surgery. However, any such operation should be delayed until at least six to twelve months after breast growth has stopped, usually a minimum of one year following the first menstrual period. The standard approach among physicians is to see young patients every six months for several years, then assess whether the option of surgery should be offered.

Pubic Hair (Pubarche)

For most girls, the second sign of puberty is the appearance of pubic hair in the pubic area. (About 10 to 15 percent will develop pubic hair before the breasts begin to bud.) At first the hair is sparse, straight and soft, but as it fills in it becomes darker, curlier and coarser. Over the next few years, the pubic hair grows up the lower abdomen, eventually taking on a triangular shape; finally it spreads to the inner thighs. About two years after the onset of pubarche, hair begins to grow under the arms as well.

Changing Body Shape

Preadolescent females acquire what, in common language, is often called “baby fat,” which may give them a more rounded belly; this development may cause considerable anxiety for these girls. That’s hardly surprising in light of our culture’s conditioning women, even from an early age, to aspire to thinness. The weight gain of puberty comes at a time when a girl may be comparing herself to the malnourished supermodels she sees worshiped in fashion advertisements or to their plasticized counterpart, the unrealistically proportioned Barbie doll.

These young female patients, and their parents, often worry that baby fat is a harbinger of impending obesity—usually the deposition of adipose tissue (connective tissue where fat is stored) around the middle is part of normal development. The body will soon redistribute the fat from the stomach and the waist to the breasts and the hips in order to mold a womanly figure. However, excessive abdominal fat, often characterized by a “D” shape, should be addressed, since obesity predisposes youngsters to diabetes, high blood pressure and other serious health concerns.

Menstruation (Menses/Menarche)

Girls often have many misconceptions and unfounded fears about menstruation. The time to begin discussing this subject with your daughter is when the breasts start to develop, heralding the arrival of puberty. Typically, one and a half to three years pass before the first menstrual period, or menarche.

Here’s how a mother or father might go about explaining the concepts of ovulation and menstruation to a twelve-year-old. It’s helpful to have on hand a book or pamphlet that includes an illustration of the female reproductive system.

“When you’re older, you’ll be able to become a mother, if you decide to. Even though that’s a long time from now, your body is already getting itself ready for the day when you choose to have a baby.

“Now that you’ve entered puberty, each month one of your two ovaries will release a ripened egg inside you. A woman becomes pregnant when a man’s sperm unites with the egg. If fertilization takes place, the fertilized egg attaches itself to the inner lining of the uterus, which is also called the womb. This is where the baby lives while it’s growing and waiting to be born. The uterus prepares for this possibility by forming a thick layer of tissue and importing extra blood, just in case.

“Most months, though, the egg doesn’t meet a sperm. Since the body won’t be needing the extra tissue and blood, it discharges the red fluid out your vagina. This is called your menstrual period, and it will happen every three to five weeks or so. During the three to seven days that you’re having your period, and for a few days afterward, you need to wear a special absorbent pad in your panties. Or you can use something called a tampon, which is made of soft cotton and goes inside your vagina.

“Menstruation is normal and healthy. It means that you are growing up. It doesn’t stop you from doing the things you want to do, like swimming or playing sports. In time, you will begin to ovulate and be capable of getting pregnant.”

Teenagers’ Common Concerns

Q: “How will I know when I’m going to get my first period?”

A: Although there’s no way to pinpoint the day, most girls reach menarche at about the same age as their mothers and older sisters did. Prepare your daughter in advance. Buy her a box of sanitary pads and show her how to wear them.

Explain that her menstruation may be highly irregular at first, with as many as six months passing between periods. Even once a girl becomes regular, any of a number of conditions can cause her to miss a cycle: sickness, stress, excessive exercise, poor nutrition and, of course, pregnancy.

If your daughter has not menstruated by age 16 or 17, or is more than a year older than her mother was at the time of menarche, consult your pediatrician. Although everything is probably normal, it’s wise to rule out any medical problems.

Q: “What if I get my period while I’m at school and have an accident?”

A: This is probably every girl’s greatest fear. Have your daughter keep a few sanitary pads in her book bag or knapsack at all times, in case of an emergency. Explain that the initial bleeding during a period is usually light, and that she should be able to get to the girls’ room or the nurse’s office in time.

Q: “Should I use sanitary pads or tampons?”

A: “I usually suggest that girls start out with pads for the first month or so, until they get used to having their period and seeing how heavy the flow is,” Dr. Felice explains. “It depends upon when a girl is ready and how comfortable she is with her body.” Some girls prefer tampons because they do not like the feeling of wetness or the odor that pads may emit. Other girls may be squeamish about inserting a tampon in their vagina and opt for pads. Buy your daughter some of each type and in absorbencies ranging from light to heavy so she can experiment to find what works best for her.

Q: “Does it hurt to have your period?”

A: The first several periods are almost always painless. Once a girl begins to ovulate, she may experience some discomfort before, during or after her period. Common symptoms include cramping, bloating, sore or swollen breasts, headaches, mood changes and irritability, and depression. Menstrual cramps, probably the most bothersome effect, can range from mild to moderate to severe. If your daughter complains of pain in the lower abdomen or back, talk to her pediatrician, who may recommend exercises and an over-the-counter pain medication such as ibuprofen.

When To Call The Doctor

Contact your daughter’s pediatrician if she experiences any of the following symptoms, or if there is any concern that there might be a problem: