Congenital heart disease (CHD)
The incidence of CHD is 1% of births. The majority of isolated CHD are multifactorial with an overall recurrence risk of 2%. However, the specific recurrence risk depends on the defect andthe family history details. It is important to distinguish isolated defects from those that are part of a syndrome with a higher recurrence risk. Preconception folate reduces the risk of congenital CHD, as well as NTD.
Cleft lip and palate
The incidence is 1 per 1,000 births. The risk of cleft lip in a second child of unaffected parents is 4%. If two children are affected, the risk of the third child being affected is 10%.
Pyloric stenosis
This condition is more common in males. The risk of the condition in the offspring of anaffected parent is much greater if that parent is female.
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Failed Pregnancy
INDUCED ABORTION
Nearly half of all pregnancies among American women are unintended, and 4 in 10 of these are terminated by abortion. A quarter of all pregnancies (excluding miscarriages) end in abortion.
• Early first-trimester abortions pose virtually no long-term risk of infertility, ectopic pregnancy, spontaneous abortion (miscarriage), or congenital malformation (birth defect), and little or no risk of preterm or low birth-weight deliveries. <0.3% of abor-tion patients experience a complication that requires hospitalization.
• Numerous epidemiologic studies have shown no association between abortion and breast cancer or any other type of cancer.
• The risk of maternal death associated with abortion increases with advancing gesta-tional age. The maternal mortality associated with childbirth is about 12 times as high as that associated with abortion.
First-Trimester Methods
Vacuum curettage dilation and curettage (D&C)
• This is the most common abortion procedure in the United States (90%), and is per-formed before 13 weeks’ gestation.
• Prophylactic antibiotics are given to reduce the infection rate, and conscious sedation and paracervical block local anesthetic are administered for pain relief.
• The cervical canal is dilated with tapered metal cervical dilators or hygroscopic/ osmotic dilators such as laminaria.
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• Complications are rare but include endometritis, treated with outpatient antibiotics; and retained products of conception (POC), treated by repeat curettage.
• Maternal mortality ratio: 1 per 100,000 women.
Medical abortion
• Mifepristone has been marketed over the past decade as an alternative to surgical abortion.
• Medical induction of abortion can be induced using oral mifepristone (Mifeprex; a progesterone antagonist) and oral misoprostol (Cytotec; prostaglandin E1). Use islimited to the first 63 days of amenorrhea.
• Approximately 85% of patients will abort within 3 days. The earlier the gestational age, the higher the success rate. About 2% of patients abort incompletely and require vacuum curettage.
• Rare cases of Clostridium sordellii sepsis have been reported.
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Second-Trimester Methods
The more advanced the gestation, the higher the rate of complications.
Dilation and evacuation (D&E)
• This is the most common second-trimester abortion procedure.
• Cervical dilation is performed by inserting osmotic laminaria dilators 24 hours prior to the procedure. The cervical dilation in millimeters equals the number of weeks of gestation (e.g., at 18 weeks, the cervix should be dilated 18 mm).
• Early second-trimester abortions (13–14 weeks) can be performed by vacuum aspira-tion. After 14 weeks, the fetus is morcellated and removed in pieces. Ultrasound guid-ance can ensure complete evacuation of pregnancy tissues.
• An intact D&E involves more advanced pregnancies, with 2 or more days of laminaria treatment to obtain wide cervical dilation allowing assisted breech delivery of the fetus under ultrasound guidance and decompression of the calvaria, with the fetus other-wise delivered intact. In lay terminology, this has been called a “partial birth” abortion.
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• Pain relief is achieved through local, intravenous, or spinal anesthesia.
• Immediate complications may include uterine perforation, retained tissue, hemor-rhage, infection, and, rarely, disseminated intravascular coagulation.
• Delayed complications may include cervical trauma with resulting cervical insufficiency.
• Maternal mortality ratio: 4 per 100,000 women.
Labor induction methods
Stimulation of uterine contractions to dilate the cervix can be achieved with any of the fol-lowing: prostaglandins (intra-amniotic PGF2a), vaginal PGE2 (dinoprostone [Cervidil®]), IM 15-methyl PGF2a (carboprost tromethamine [Hemabate®]), PGE1 (misoprostol [Cytotec®]).
Interval from induction to delivery may be up to 24 hours.
Delivery of a live fetus may occur with use of prostaglandin (PG) analogs; feticidal agents used include intracardiac injection of KCl or digoxin.
Immediate complications include retained placenta (the most common problem with all PGabortions), hemorrhage, and infection. Delayed complications include cervical trauma with resulting cervical insufficiency.
Maternal mortality ratio: 8 per 100,000 women.
Methods of Induced Abortion
| Trimester | Method | Procedure | Maternity- | ||
| Mortality Ratio | |||||
| First | Surgical | Suction dilation & curettage (D&C) | 1 | ||
| Trimester | |||||
| Medical | Mifepristone (progesterone antagonist) | 1 | |||
| Second | Surgical | Dilation & evacuation (D&E) | 4 | ||
| Trimester | |||||
| PGE1
| Induction of labor contractions | 8 | |||
| Any | Major | Hysterotomy, hysterectomy | 25 | ||
| Trimester | surgery | ||||
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EARLY PREGNANCY BLEEDING
Chapter 2 l Failed Pregnancy
Note
A 40-year-old woman (G3 P1 Ab1) at 9 weeks’ gestation comes to the office complaining of vaginal bleeding. A urine pregnancy test was positive 3 weeks ago. She initially experienced breast tenderness; however, it has now disappeared. She denies passage of any tissue vaginally.
Definition. Bleeding that occurs before12 weeks’ gestation. Themost common cause of earlypregnancy loss is fetal in origin.
Etiology
• Cytogenetic etiology. The majority of early pregnancy losses are caused by gross chro-mosomal abnormalities of the embryo or fetus.
• Mendelian etiology. Other losses may be caused by autosomal or X-linked dominantor recessive diseases.
• Antiphospholipid syndrome. An uncommon cause of early pregnancy loss. Some womenwith SLE produce antibodies against their own vascular system and fetoplacental tissues. Treatment is subcutaneous heparin.
For more discussion about antiphospholipid syndrome, refer to the thrombophilias section in chapter 10.
Clinical Presentation: Speculum examination is essential to rule out vaginal or cervical lesionsthat are causing bleeding.
• RhoGAM should be administered to all Rh-negative gravidas who undergo dilatationand curettage (D&C).
• Molar and ectopic pregnancy should be ruled out in all patients with early pregnancy bleeding.
Clinical Entities
The following diagnoses represent findings along a continuum from the beginnings of losing the pregnancy to complete expulsion of the products of conception (POC).
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Missed abortion
Sonogram finding of a nonviable pregnancy without vaginal bleeding, uterine cramping, or cervical dilation. Management: Scheduled suction D&C, conservative management await-ing a spontaneous completed abortion, or induce contractions with misoprostol (Cytotec®) (PGE 1).
Threatened abortion
Sonogram finding of a viable pregnancy with vaginal bleeding but no cervical dilation. Half of these pregnancies will continue to term successfully. Management: Often the cause is implan-tation bleeding. Observation. No intervention is generally indicated or effective.
Inevitable abortion
Vaginal bleeding and uterine cramping leading to cervical dilation, but no POC has yet been passed. Management: Emergency suction D&C if bleeding is heavy to prevent further blood loss and anemia. Otherwise conservative management awaiting a spontaneous completed abortion or induce contractions with misoprostol (Cytotec®) PGE 1.
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Incomplete abortion
Vaginal bleeding and uterine cramping leading to cervical dilation, with some, but not all, POC having been passed. Management: Emergency suction D&C if bleeding is heavy to prevent further blood loss and anemia. Otherwise conservative management awaiting a spontaneous completed abortion or induce contractions with misoprostol (Cytotec(R)) PGE1.
Completed abortion
Vaginal bleeding and uterine cramping have led to all POC being passed. This is confirmed by a sonogram showing no intrauterine contents or debris. Management: Conservative if an intrauterine pregnancy had been previously confirmed. Otherwise, serial b-human chorionic gonadotropin (b-hCG) titers should be obtained weekly until negative to ensure an ectopic pregnancy has not been missed.
FETAL DEMISE
A 28-year-old multigravida at 33 weeks’ gestation comes to the office stating she has not felt her baby move for 24 hours. A previous 18-week sonogram showed a single fetus with grossly normal anatomy. You are unable to find fetal heart tones by auscultation with a Doppler stethoscope.
Definition. From a medical viewpoint, the term applies to any death after the embryo period (≥10 menstrual weeks). From a perinatal statistics viewpoint, the term applies toin uterodeath of a fetus after 20 weeks’ gestation before birth. Antenatal demise occurs before labor. Intrapartum demise is the term if death occurs after the onset of labor.
Significance
• Disseminated intravascular coagulation (DIC) is the most serious consequence with prolonged fetal demise (>2 weeks) resulting from release of tissue thromboplastin from deteriorating fetal organs.
• Grief resolution may be prolonged if psychosocial issues are not appropriately addressed.
Risk Factors. Fetal demise is most commonlyidiopathic. When a cause is identified, risk factorsinclude antiphospholipid syndrome, overt maternal diabetes, maternal trauma, severe maternal isoimmunization, fetal aneuploidy, and fetal infection.
Presentation
• Before 20 weeks’ gestation, the most common finding is uterine fundus less than dates.
• After 20 weeks’ gestation, the most common symptom is maternal report of absence of fetal movements.
Diagnosis. Ultrasound demonstration of lack of fetal cardiac activity.
Management
• DIC present. DIC is usually not seen until 4 weeks after demise. Coagulopathy shouldbe ruled out with appropriate laboratory testing: platelet count, d-dimer, fibrinogen, prothrombin time, partial thromboplastin time. If DIC is identified, immediate deliv-ery is necessary with selective blood product transfusion as clinically indicated.
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Chapter 2 l Failed Pregnancy
• No DIC present. Delivery may best be deferred for a number of days to allow for anappropriate grief response to begin. Or if the patient wishes conservative management, follow weekly serial DIC laboratory tests. Ninety percent of patients start spontaneous labor after 2 weeks.
• Mode of delivery. A dilatation and evacuation (D&E) procedure may be appropriatein pregnancies of <20 weeks’ gestation if no fetal autopsy is indicated. Induction of labor with vaginal prostaglandin is appropriate in pregnancies of >20 weeks or if a fetal autopsy is indicated. Cesarean delivery is almost never appropriate for dead fetus.
• Psychosocial issues. Acceptance of the reality of the loss may be enhanced by allowingthe patient and her family to see the fetus, hold the fetus, name the fetus, and have a burial. Encouraging expression of feelings and tears may speed grief resolution.
• Identify cause. Workup may include cervical and placental cultures for suspectedinfection, autopsy for suspected lethal anatomic syndrome, karyotype for suspected aneuploidy, total body x-ray for suspected osteochondrodysplasia, maternal blood for Kleihauer-Betke (peripheral smear for suspected fetomaternal bleed). Amniocentesiscan yield living fetal amniocyte cells although the fetus is demised. Up to 10% of the karyotypes show aneuploidy.
ECTOPIC PREGNANCY
A 28-year-old patient visits the emergency department complaining of unilateral left-sided abdominal pain and vaginal spotting of 3 days’ duration. Her last menstrual period was 8 weeks ago, and before this episode she had menses every 28 days. Her only previous pregnancy was an uncomplicated term spontaneous vaginal delivery. She had used intrauterine contraception for 3 years in the past. On pelvic examination the uterus is slightly enlarged and there is left adnexal tenderness but no palpable mass. A quantitative serum b-hCG value is 2,600 mIU.
Definition. This is a pregnancy in which implantation has occurred outside of the uterinecavity. The most common location of ectopic pregnancies is an oviduct. The most common location within the oviduct is the distal ampulla.
Differential Diagnosis. With a positive pregnancy test, the differential diagnosis consists ofa threatened abortion, incomplete abortion, ectopic pregnancy, and hydatidiform mole. In a reproductive age woman with abnormal vaginal bleeding, the possibility of pregnancy or com-plication of pregnancy should always be considered.
Risk Factors. The most common predisposing cause is previous pelvic inflammatory disease(PID). Ectopic pregnancy risk is increased from any obstruction of normal zygote migration to the uterine cavity from tubal scarring or adhesions from any origin: infectious (PID, IUD), postsurgical (tubal ligation, tubal surgery), or congenital (diethylstilbestrol [DES] exposure). One percent of pregnancies are ectopic pregnancies, and if the patient has had one ectopic pregnancy, the incidence becomes 15%.
GYN Triad
Ectopic Pregnancy
• Secondary amenorrhea
• Unilateral abdominal/pelvic pain
• Vaginal bleeding
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