A baby starts to develop its reproductive organs between weeks 4 and 5 of pregnancy. This development continues until the 20th week of pregnancy.
The development is a complex process. It can be interrupted by many things. How severe your baby's problem is depends on when the interruption occurred. In general, the problem will be more widespread the earlier development problems occur in the womb. Problems in the development of a girl's reproductive organs may be caused by:
- Broken or missing genes (genetic defect)
- Use of certain drugs during pregnancy
For example, some babies may have a genetic defect that prevents their body from producing an enzyme (protein) called 21-hydroxylase that the adrenal gland needs to make hormones such as cortisol and aldosterone. This condition is called congenital adrenal hyperplasia. If a developing baby girl lacks this enzyme, she will be born with a uterus, ovaries, and fallopian tubes. However, her external genitals will look like those found on boys.
Certain drugs that the mother takes can pass into the baby's bloodstream and interfere with organ development. One drug known to do this is diethylstilbestrol (DES). Health care providers once prescribed this medicine to pregnant women to prevent miscarriage and early labor. However, scientists learned that baby girls born to women who took this drug had an abnormally shaped uterus. The drug also increased the daughters' chances of developing a rare form of vaginal cancer.
Sometimes, a developmental disorder can be seen as soon as the baby is born. It may cause life-threatening conditions in the newborn. Other times, the condition is not diagnosed until the girl is older.
The reproductive tract develops close to the urinary tract and kidneys. It also develops at the same time as several other organs. As a result, developmental problems in the female reproductive tract sometimes occur with problems in other areas, including the urinary tract, kidneys, intestine, and lower spine.
Developmental disorders of the female reproductive tract include intersex and ambiguous genitalia.
Other developmental disorders of the female reproductive tract include:
- Cloacal abnormalities: The cloaca is a tube-like structure. In the early stages of a baby's development, the urinary tract, rectum, and vagina all empty into this single tube. But, later in development, the 3 areas separate and have their own openings. If the cloaca persists as a baby girl grows in the womb, all the openings do not form and separate. For example, a baby may be born with only 1 opening on the bottom of the body near the rectal area. Urine and feces cannot drain out of the body. This can cause stomach swelling and breathing problems. Some cloacal abnormalities may cause a baby girl to look like she has a male's penis. These birth defects are rare.
- Problems with outer (external) genitals: Developmental problems may lead to a swollen clitoris or fused labia (when the folds of tissue around the opening of the vagina are joined together). Most other problems of the outer genitals are related to intersex and ambiguous genitalia.
- Imperforate hymen: The hymen is a thin tissue that partly covers the opening to the vagina. An imperforate hymen completely blocks the vaginal opening. This often leads to painful swelling of the vagina. Sometimes, the hymen has only a very small opening or tiny small holes. This problem may not be discovered until puberty. Some baby girls are born without a hymen. This is not considered abnormal.
- Ovarian problems: A baby girl may have an extra ovary, extra tissue attached to an ovary, or structures called ovotestes that have both male and female tissue.
- Uterus and cervix problems: A baby girl may be born with an extra cervix and uterus, a half-formed uterus, or a blockage of the uterus. Usually, girls born with half a uterus and half a vagina are missing the kidney on the same side of the body.
- Vaginal problems: A baby girl may be born without a vagina or have the vaginal opening blocked by a layer of cells that are higher up in the vagina than where the hymen is. A missing vagina is most often due to Mayer-Rokitansky-Kuster-Hauser syndrome. In this syndrome, the baby is missing part or all of the internal reproductive organs (uterus, cervix, and fallopian tubes). Other abnormalities include having 2 vaginas or a vagina that opens into the urinary tract, a heart-shaped uterus, and a uterus with a wall in the middle of the cavity.