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Vaginal abnormalities that result in infertility are not common
but are important to recognize. Normally, the vaginal vault is
the location where the sperm are deposited during intercourse.
Barriers to the completion of vaginal intercourse may be largely
psychological (such as vaginismus) or anatomic (such as congenital
abnormalities of the introitus, an imperforate hymen, vaginal
septums). Once deposited in the vaginal vault the sperm must rapidly
move from the semen to the cervical mucus, which is the only location
in the vagina that has "friendly" characteristics and
allows long-term (days rather than minutes to hours) sperm survival.
* (1) Vaginismus
This is the involuntary spasm of the muscles at the opening of
the vaginal vault, preventing penetration with the penis or resulting
in painful intercourse. There are degrees of spasm, some of which
may be relieved with reassurance and others that totally prevent
atraumatic penetration. The psychological basis for vaginismus
is not always clear, but may be associated with early sexual abuse
or early teaching that sexual relations are immoral or evil. Once
the basis underlying vaginismus is recognized by the affected
woman, she can often successfully "relearn" what intercourse
means for herself and relieve the spasm. Occasionally, professional
counseling is appropriate.
* (2) Orgasmic dysfunction
This is a concern of some couples. In fact, reports cite that
up to 15% of women have never experienced an orgasm and up to
35% of women do not experience orgasm on any particular sexual
occasion. In terms of fertility, however, orgasm is not thought
to be necessary. Evidence for this includes the success of procedures
designed to improve fertility without orgasm (such as intrauterine
inseminations of sperm in the doctor's office and IVF with embryo
transfer).
* (3) The external genitalia of the female
There are a variety of congenital defects of the female external
genitalia that impact on fertility.
If the developing female fetus (while inside the mother's womb)
is exposed to high levels of androgenic hormones (the "male"
hormones) then defects of the external genitalia might include
a) fusion of the labia
Usually starts posteriorly (nearer the rectum) and progresses
anteriorly (toward the clitoris), with different degrees of fusion
depending on the timing and amount of androgenic exposure. This
fusion may limit the size of the vaginal orifice. The most common
cause for excessive fetal androgen exposure is congenital adrenal
hyperplasia (CAH). CAH is a genetic abnormality that results in
a deficiency of one of the enzymes required for cortisol biosynthesis.
In CAH the precursor hormones for cortisol are forced into a biosynthetic
pathway that leads to androgen hormone formation. Androgen excess
may also occur if the mother of the female fetus ingests medications
containing androgenic compounds (such as Danazol or Testosterone).
b) clitoral enlargement
This can be dramatic possibly even making it difficult to distinguish
the clitoris from a penis at birth. Clitoral enlargement does
not have a clear impact on fertility.
Other vaginal defects that are not clearly hormonally based include
a) imperforate hymen
The hymen is normally perforated slightly prior to birth so that
there is a small connection between the inside of the vagina and
the outside. This abnormality in which there is no perforation
usually is noted at puberty when the initial menstrual flow is
obstructed within the vaginal vault, often causing pain and the
buildup of blood within the vagina and uterus. Because the fallopian
tubes are patent, the flow can occur into the pelvis and there
is a higher percentage of endometriosis in these patients. Excision
of the imperforate hymen is usually a straightforward surgical
procedure.
b) transverse vaginal septum
Results from an incomplete canalization of the vagina during fetal
development. There are a large variety of possible septums, ranging
from complete and thick to incomplete and narrow. If there is
a complete septum, then there will be a buildup of blood in the
vagina and uterus with similar consequences as seen with the imperforate
hymen. Transverse vaginal septums are sometimes very difficult
to repair and should only be attempted by an experienced vaginal
surgeon.
c) vaginal agenesis
Congenital absence of the vagina and uterus is known as the "Rokitansky-Kuster-Hauser-Mayer"
syndrome. This syndrome is uncommon but is the second leading
cause of primary amenorrhea (ovarian dysgenesis is the leading
cause) and is associated with a 35% chance of urologic abnormalities
and 10-15% chance of skeletal anomalies. Chromosome analysis is
recommended for these patients. The ovaries are usually normal,
so that theoretically one could use the woman's eggs for IVF along
with a surrogate uterus. Generally, the creation of a vaginal
pouch with either dilators or surgery makes intercourse possible.
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