The ovulation process is important if subsequent fertilization is to take place. This is an exquisitely timed
phenomenon dependent on a host of hormonal interactions involving a variety of endocrine glands.
Tubal function must also be adequate or the ovum will not be picked up by the fallopian tube to be
fertilized within the ampulla.
Following ovulation, the ovum with its cumulus oophorus cells are picked up by the fimbria of the
fallopian tube. The ovum has now formed the first polar body. It remains in the ampulla portion of the
tube and is viable for about 18 to 24 hours. If fertilization does not occur, the ovum disintegrates and is
destroyed by the tube. Sperm will remain viable in the female reproductive tract for about 48 hours,
although this can be quite variable. Sperm present in the ampulla meet the cumulus oophorus mass and
penetrate by chemical and mechanical means to reach the zona pellucida. One sperm penetrates the
zona pellucida, the second polar body is formed, and the nuclear material of the sperm enters the
vitelline membrane. The diploid chromosome number is re-established, and mitotic cell division can
now occur.
After fertilization occurs, the ovum remains in the fallopian tube for about 72 hours. During this time
there are several cellular division, but the size of the fertilized ovum does not increase. Around 72 hours
the zona pellucida fragments and falls away. The ovum enters the uterine cavity for 60 to 72 more
hours, and the central cavity begins to form. A definite cell mass is formed on one side of the blastocyst
by the time implantation occurs. The trophoblast cells burrow into the endometrial stroma to form
syncytiotrophoblast. Primitive amniotic and chorionic cavities begin to form, and a germ disk is
recognizable soon after implantation.
Most women suspect pregnancy before seeking confirmation. However, it is sometimes necessary to
differentiate pregnancy from other causes of uterine enlargement and/or amenorrhea. The signs and
symptoms are as follows:
Presumptive
a. Cessation of menses (amenorrhea).
b. Breast changes.
c. Vaginal discoloration.
d. Skin pigmentation.
e. Morning sickness.
f. Perception of fetal movements (quickening).
g. Urinary frequency.
h. Fatigue.
Probable
a. Abdominal enlargement.
b. Uterine and cervical changes (shape, size, consistency).
c. Intermittent uterine contractions.
d. Ballottement of fetus.
e. Palpation of fetal parts.
f. Positive hormonal (hCG) tests.
Positive
a. Fetal heart tones heard or recorded.
b. Fetal movements perceived by examiner.
c. Fetus identified ultrasonically or radiologically.
The diagnosis is substantiated by the appearance of softening of the cervix on pelvic examination
(Goodell,s sign), a purple hue of the vagina and cervix (Chadwick,s sign) and compressibility and
softening of the isthmus (Hegar,s sign) by six to eight weeks, gestation. Abdominal signs of pregnancy
appear somewhat later. From 14 weeks, enlargement of the uterus is palpable abdominally. Fetal
movement is felt by 18 to 20 weeks (quickening), and fetal heart tones are heard with the fetoscope
slightly later. With the doppler, fetal life can be confirmed much earlier (9 to 12 weeks) than with
conventional auscultation methods.
The biochemical test for pregnancy has evolved from dependence on laboratory animals to rapid
accurate assays of human chorionic gonadotropin (hCG) produced by the syncytiotrophoblast.
Pregnancy tests generally available currently are enzyme immunoassays (E.I.A.) utilizing monoclonal
antibodies specific for hCG, thus avoiding false positive reactions with luteinizing hormone. Serum or
urine may be tested, and both cost about the same and can be run in about ten minutes. It is sensitive to
about 25 mIU/mL, making it reliable soon after implantation which occurs seven or eight days after
ovulation. At approximately the time a woman expects her menses to begin, her hCG concentration will
be about 100 mIU/mL if she is pregnant. Therefore commercial urine home pregnancy tests are
generally positive by that time. Home pregnancy tests are considered qualitative (yes or no) tests as
opposed to quantitative tests.
Serum radioimmunoassay beta subunit (RIA-hCG-b) testing measures only beta subunit hCG. It is
sensitive to approximately 5 mIU/mL and is particularly useful for diagnosing pregnancy very early.
Serial quantitative RIA-hCG-b analyses are helpful in diagnosing ectopic pregnancies, distinguishing
viable pregnancies from non-viable ones and for monitoring trophoblastic diseases (such as hydatidiform
mole).
Errors may be caused by uterine fibroids and ovarian cysts which may be confusing by their size. Other
sources of diagnostic error are premature menopause, obesity, and other endocrine causes of
amenorrhea. Pseudocyesis (a psychiatric condition where a woman feels and fully believes she is
pregnant when she is not) may be accompanied by many of the subjective symptoms and signs of true
pregnancy, but the pelvic signs of pregnancy are absent and the laboratory tests are negative. Lastly,
ectopic or tubal pregnancy should always be kept in mind in any woman of reproductive age who
develops menstrual abnormalities and pelvic pain along with symptoms of pregnancy.
Definition: The natural termination of pregnancy prior to the 20th week of gestation or with fetal weight
less than 500 gm.
Clinical Classification:
Threatened Abortion: Uterine bleeding in early pregnancy, with or without cramping.
Inevitable Abortion: Symptoms of threatened abortion plus the physical finding of dilatation of the internal os of the cervix.
Incomplete Abortion: Passage of a portion of the products of conception from the
uterus.
Complete Abortion: Passage (grossly) of all of the products of conception from the
uterus.
Missed Abortion: Retention of the conceptus in the uterus for a clinically appreciable
time after death of the embryo or fetus.
Habitual Abortion: The usual criterion is three or more consecutive abortions.
Incidence: Clinically recognizable spontaneous abortion occurs in 15% to 20% of pregnancies, the
majority occurring in the first three months. It is probable that at least as many abortions occur very
early in pregnancy without recognition of the event.
Developmental anomalies in more than 60% of cases (Hertig).
Chromosome abnormalities (22% in Carr,s study).
B. Maternal factors (less common, but more often treatable).
Systemic diseases.
a. Infections transmitted to the fetus (viral, bacterial, protozoal).
b. Febrile illness without fetal infection.
c. Peritonitis secondary to infection or surgery.
d. Hypertensive vascular disease.
e. Severe metabolic disorders (diabetes, thyroid dysfunction).
f. Chronic debilitating disease states.
Inadequate progesterone production (corpus luteum or placenta) is a definite but probably infrequent cause.
Immunologic Factors - Women expressing serum Lupus anticoagulant and anticardiolipin antibodies in high titers are at increased risk of abortion (antiphospholipid syndrome).
Trauma - a rare factor.
Psychosomatic - suspected but unproven factor.
Uterine abnormalities.
a. Malformation, especially septate uterus.
b. Myoma (submucous).
c. Intrauterine synechiae (bands).
d. Incompetent cervix.
A uterine abnormality is particularly suspect with repeated late abortion (second trimester).
Hemorrhage - More common with late abortions. Continued heavy bleeding indicates retained tissue (incomplete abortion).
Infection (septic abortion) seen most commonly with criminally-induced abortion but
may ensue in spontaneous or therapeutic abortion. Septic shock may occur in severe
instances.
If a missed abortion is retained beyond one month, thromboplastin passage into the
maternal circulation may result in a clotting disorder (DIC). This risk is greater in late
abortion.
Threatened Abortion - no specific therapy is rational since the majority of abortions
result from failure of normal fetal development and the fetus usually is dead by the time
of onset of bleeding. Management is directed toward avoiding the complications of
infection or excessive blood loss.
Of all women who present uterine bleeding in early pregnancy, fewer than half proceed
to abortion.
Inevitable and incomplete abortion - the aim of therapy is prompt evacuation of the
uterus to prevent hemorrhage or infection.
Intravenous oxytocin infusion.
Removal of tissue with sponge forceps and uterine curettage (suction or
instrumental).
An exception in the management of "inevitableo/oo abortion is that of
cervical incompetence. In this condition painless dilatation of the cervix
has occurred (without bleeding) in the mid trimester. In this
circumstance, a purse-string suture of the cervix (cerclage) may succeed
in retaining the pregnancy.
Complete Abortion: No further therapy is required, but the patient must be
observed closely for continued bleeding or evidence of infection. These complications
most often indicate that not all of the tissue has been passed.
Missed Abortion: Most missed abortions will evacuate spontaneously and should
then be evaluated for completion of the process. If uterine evacuation is delayed
beyond four weeks, intervention to empty the uterus should be considered to prevent a
coagulation disorder.
Defined: Ectopic pregnancy refers to implantation of the zygote outside the uterus or in an abnormal location within the uterus.
Incidence.
Varies widely from study to study.
Probably dependent on population base (Jamaica 1:28).
From 1:64 to 1:350, but generally accepted at 1:130.
Recently has shown increasing frequency.
Mortality.
Felt to be responsible for 10% of maternal deaths.
Approximate maternal mortality: 1-2/1,000.
Etiology.
Chronic PID.
Tubal damage (previous surgery, endometriosis).
Hormonal factors slowing ovum transport.
Menstrual bleeding (unsuppressed).
Tubal atony or spasm.
Blighted conceptus - features of blighted ovum are seen twice as
often in tubal pregnancies.
Developmental abnormalities of the tube.
Extrinsic obstruction.
IUD usage.
Pathology: "Normalo/oo conceptus but with pathologic site.
Uterine changes.
In first two months uterus growth may be comparable to normal pregnancy due to the circulating hormonal changes of early pregnancy.
Decidual changes.
Arias-Stella ("Sturgis-Arias-Stellao/oo): Secondary to hyperstimulation by progesterone and estrogen (occurs in 60%), suggestive of tubal ectopic pregnancy.
Clinical history will give greatest amount of useful information.
Clinical history - negative history of amenorrhea in 25%.
Pain - most common symptom - more than 90%.
Syncope - 33%.
Physical exam.
Signs of hypovolemia - 33% heart rate - blood
pressure.
Pelvic mass - 50%.
Pelvic pain - especially with movement of cervix.
Temperature.
(1) May be subnormal with acute blood
loss.
(2) May be elevated when patient
stable (2%).
Diaphragmatic irritation - 10%.
Lab data.
CBC with differential.
(1) Hct - Hbg: almost always low.
(2) Leukocytosis: 50% greater than
15,000/cu mm.
Pregnancy testing: almost always positive with RIA or EIA tests.
Ultrasonography: A gestational sac should be seen using a transvaginal ultrasound probe when the serum quantitative bhCG exceeds 2,500 mIU/mL (even 1,000 at some centers) in a normal intrauterine gestation. The inability to detect an ectopic pregnancy ultrasonographically DOES NOT rule out the possibility of ectopic pregnancy.
Surgical Diagnostic Options.
Culdocentesis: quick and simple with extremely high correlation in ruptured ectopics (90% to 95%).
D & C.
(1) Only 20% will show decidual
response.
(2) Questionable value.
Laparoscopy: especially if diagnosis is only a
suspicion.
Differential diagnosis.
Ectopic pregnancy
Pelvic inflammatory disease.
Abortion: threatened or incomplete.
Ovarian pathology: torsion, cyst.
Acute appendicitis.
Treatment.
Lab: CBC, ABO-Rh, cross match, electrolytes, UA.
Stabilize patient.
Salpingectomy.
Ipsilateral oophorectomy with ovarian involvement.
Conservative approach.
Resection.
Expression.
Evacuation.
Linear salpingostomy.
Contralateral tube.
Hysterectomy: criteria.
The Rh negative patient.
Medical treatment: single dose IM methotrexate, hyperosmolar
glucose.
Prognosis.
Tubal pregnancy interferes with future reproductive ability in 50% to 60%.
Recurrent tubal pregnancy ranges from 7.7% to 20%.
The number one reason for amenorrhea in a woman of reproductive age is pregnancy.
The diagnosis of early pregnancy is not always straightforward; clinicians from all disciplines
must become expert in the methods of diagnosing pregnancy.
The most common disorder of early pregnancy is abortion in all its varied presentations.
The most life-threatening disorder of early pregnancy is ectopic pregnancy. High suspicion for
ectopic pregnancy should always be maintained for gynecologic patients, and prompt diagnosis
and therapy should be reflexive.