Ans. is D. i.e. All are correct

Characteristics of autosomal recessive disorders

Autosomal recessive inheritance is the single largest category of Mendelian disorders.

They have the following features :

• The trait does not usually affect the parents but siblings may show the disease (Option “c” is correct).
• Siblings have one chance in four of being affected (i.e. recurrence risk is 25% for each birth).
• Consanguinity may be the cause (option a is correct).
• The expression of the defect tends to be more uniform than in autosomal dominant disorders.
• Complete penetrance is common (Option b is correct).
• Onset is frequently early in life.

In the question the lady has recurrent abortions and H/o autosomal recessive disorder in the family, therefore all features of autosomal recessive disorders apply to her

Ans. is D. i.e All (Trisomy 21; Monosomy; and Trauma)

Ans. C i.e. Embryo

• The most common cause of abortion in the first trimester is chromosomal abnormalities involving the zygote or embryo.
• Approximately half of the miscarriages are anembryonic, that is, with no identifiable embryonic elements. Less accurately, the term blighted ovum may be used.
• The other 50 % are embryonic miscarriages, which commonly display a developmental abnormality of the zygote, embryo, fetus, or at times, the placenta.
• Of embryonic miscarriage, half of these—25 percent of all abortuses—have chromosomal anomalies and thus are aneuploid abortions.
• The remaining cases are euploid abortions, that is, carrying a normal chromosomal complement.

Trisomy 16

• Trisomy 16 is the most common trisomy found with first-trimester losses, accounting for 18.3 percent, but it is not identified later in gestation.

Ans. is D. i.e. None
COMMON CAUSES OF MISCARRIAGE:
First trimester:
* Genetic factors (50%)
* Endocrine disorders (LPD, thyroid abnormalities, diabetes)
* Immunological disorders (autoimmune and alloimmune)
* Infection:
  – Viral: Rubella, Cytomegalovirus, Variola, Vaccinia or HIV.
  – Parasitic: Toxoplasma, Malaria
Bacteria: Ureaplasma, Chlamydia,Syphilis ,Brucella.
* Unexplained.
Second trimester: 
* Anatomic abnormalities
* Cervical incompetence (congenital or acquired)
* Müllerian fusion defects (bicornuate uterus, septate uterus)
* Uterine synechiae.
* Uterine fibroid
* Maternal medical illness
* Unexplained

Ans. is A. i.e. Incompetent cervix
Some Causes of Midtrimester Spontaneous

• Fetal anomalies
  • Chromosomal
  • Structural
• Uterine defects
  • Congenital
  • Leiomyomas
  • Incompetent cervix
• Placental causes
  • Abruption, Previa
  • Defective spiral artery transformation
  • Chorioamnionitis
• Maternal disorders
  • Autoimmune
  • Infections
  • Metabolic

Ans. is A. i.e. Ovo Fetal factor

• Approximately half of the miscarriages are anembryonic, that is, with no identifiable embryonic elements. Less accurately, the term blighted ovum may be used.
• The other 50 percent are embryonic miscarriages, which commonly display a developmental abnormality of the zygote, embryo, fetus, or at times, the placenta.

Ans. is D. i.e. Before 20^th week of gestation or 500 gms (weight of fetus)

• National Center for Health Statistics, the Centers for Disease Control and Prevention, and the World Health Organization all define abortion as pregnancy termination before 20 weeks’ gestation or with a fetus born weighing < 500 g.
• These criteria, however, are somewhat contradictory because the mean birth weight of a 20-week fetus is 320 g, whereas 500 g is the mean for 22 to 23 weeks

Autosomal trisomy

• With first-trimester miscarriages, autosomal trisomy is the most frequently identified chromosomal anomaly.
• Although most trisomies result from isolated nondisjunction, balanced structural chromosomal rearrangements are found in one partner in 2 to 4 percent of couples with recurrent miscarriages.
• Trisomies have been identified in abortuses for all except chromosome number 1, and those with 13, 15, 16, 18, 21, and 22 are most common.
• Single autosomal trisomies represent the largest class of chromosome abnormalities in spontaneous miscarriages. 
• Trisomy 16 is the most frequent one (18.7% of the single autosomal trisomies), followed by trisomy 22 (18.5%), trisomy 15 (14.2%), and trisomy 21 (12.2%)

Ans. D. Before 16 weeks

• Abortion is the expulsion or extraction from its mother of an embryo or fetus weighing 500 g or less when it is not capable of independent survival (WHO).
• This 500 g of fetal development is attained approximately at 22 weeks (154 days) of gestation.
• The expelled embryo or fetus is called an abortus. The word miscarriage is the recommended terminology for spontaneous abortion.
• More than 80 percent of spontaneous abortions occur within the first 12 weeks of gestation.

Ans. is D. i.e. Less than 500 gm

• Abortion is the expulsion or extraction from its mother of an embryo or fetus at less than 20 weeks, or weighing 500 g or less when it is not capable of independent survival.
• Period of viability depends on the medical facilities of a country and hence varies.
• As per WHO-22 weeks.
• As per ACOG-24 weeks.
• In India: beyond 28 weeks, Fetus is l00% viable.

Weight of fetus

• At 20 weeks, the weight of fetus-300 gm
• Between 22-23 weeks-500 gm.
• At 24 weeks, the weight of fetus-630 gms.
• At 28 weeks, the weight of fetus-1 kg
• 500 g of fetal development is attained approximately 22 weeks (154 days) of gestation.

Ans. is A. i.e. Mullerian fusion defects

• Mullerian duct anomaly is an important cause of recurrent miscarriage in early and mid-trimester.
• Septate or arcuate uterus is the most common uterine anomaly associated with Mullerian fusion defects and it is the most common defect associated with repeated pregnancy loss.
• In septate uterus: both Mullerian duct fuse & form septa but septa fails to resolve. So the uterus is outwardly normal but contains a complete or incomplete septum inside.
• In the arcuate uterus, the fundus of the uterus remains flat & does not become dome-shaped.
• on HSG in the septate uterus, an angle of less than 75° between the uterine horns is suggestive of a septate uterus, and an angle of more than 105° is more consistent with bicornuate uteri.
• Management for septate uterus:

1. Earlier: Jones/Tompkins Metroplasty was done.
2. Nowadays: Hysteroscopic resection of septa is being done after inducing endometrial atrophy by administering the GnRH analogue for 2 months.

• Main complications: Uterus perforation and fluid overload.

Ans. C. i.e. First-trimester abortion
COMMON CAUSES OF MISCARRIAGE:
First trimester:
* Genetic factors (50%)
* Endocrine disorders (LPD, thyroid abnormalities, diabetes)
* Immunological disorders (autoimmune and alloimmune)
* Infection:
  – Viral: Rubella, Cytomegalovirus, Variola, Vaccinia or HIV.
  – Parasitic: Toxoplasma, Malaria
-Bacteria: Ureaplasma, Chlamydia,Syphilis ,Brucella.
* Unexplained.
Second trimester:
* Anatomic abnormalities
* Cervical incompetence (congenital or acquired)
* Müllerian fusion defects (bicornuate uterus, septate uterus)
* Uterine synechiae.
* Uterine fibroid
* Maternal medical illness
* Unexplained

Ans.A. Before viability

• Abortion is the expulsion or extraction from its mother of an embryo or fetus at less than 20 weeks, or weighing 500 g or less when it is not capable of independent survival.
• Periods of viability depends on the medical facilities of a country and hence varies.
• As per WHO-22 weeks.
• As per ACOG-24 weeks.
• In India: beyond 28 weeks, Fetus is 100% viable.

Ans. is A. i.e. Chromosomal defect
Fetal factors: 

• Chromosomal abnormalities (M/C first trimester cause)
• Hydropic degeneration of villi
• twin/multiple pregnancies

Maternal factors

• Maternal infections: TORCH infections, Malaria, Ureaplasma, Chlamydia, Brucella, Spirochaetes
• Maternal medical disorders: Hypertension, Chronic renal disease, Cyanotic heart disease, Hemoglobinopathies.
• Environmental factors: Alcohol, Smoking (leads to early pregnancy loss), Caffeine
• Exposure to radiation: (> 5 rads) and anesthetic gases.
• Endocrine problems: Luteal phase defect (deficiency of progesterone), Thyroid abnormalities – hypothyroidism, Poorly controlled diabetes mellitus, PCOD, Hyperprolactinemia
• Immunological causes: Antiphospholipid antibody syndrome (APLA syndrome), Inherited thrombophilias
• Uterine factors like Cervical incompetence (M/C 2nd trimester), Mullerian anomalies (M/C associated with abortions is the septate uterus), Large and multiple submucous leiomyomas, Asherman syndrome, DES exposure in utero.
• Weight of mother: Underweight or nutritional deficiency does not lead to abortion, Obesity leads to abortion.
• Others: Trauma, Subchorionic hematoma Defective placentation.

Paternal factors: Increased paternal age is associated with increased abortion.

Ans. Cervical incompetence
Fetal factors: 

• Chromosomal abnormalities (M/C cause)
• Hydropic degeneration of villi
• twin/multiple pregnancies

Maternal factors

• Maternal infections: TORCH infections, Malaria, Ureaplasma, Chlamydia, Brucella, Spirochaetes
• Maternal medical disorders: Hypertension, Chronic renal disease, Cyanotic heart disease, Hemoglobinopathies.
• Environmental factors: Alcohol, Smoking (leads to early pregnancy loss), Caffeine
• Exposure to radiation: (> 5 rads) and anesthetic gases.
• Endocrine problems: Luteal phase defect (deficiency of progesterone), Thyroid abnormalities – hypothyroidism, Poorly controlled diabetes mellitus, PCOD, Hyperprolactinemia
• Immunological causes: Antiphospholipid antibody syndrome (APLA syndrome), Inherited thrombophilias
• Uterine factors like Cervical incompetence (M/C 2nd trimester), Mullerian anomalies (M/C associated with abortions is the septate uterus), Large and multiple submucous leiomyomas, Asherman syndrome, DES exposure in utero.
• Weight of mother: Underweight or nutritional deficiency does not lead to abortion, Obesity leads to abortion.
• Others: Trauma, Subchorionic hematoma Defective placentation.

Paternal factors: Increased paternal age is associated with increased abortion.

Ans. is A. i.e. Genetic
Causes of abortion
Fetal factors: 

• Chromosomal abnormalities (M/C cause)
• Hydropic degeneration of villi
• twin/multiple pregnancies

Maternal factors

• Maternal infections: TORCH infections, Malaria, Ureaplasma, Chlamydia, Brucella, Spirochaetes
• Maternal medical disorders: Hypertension, Chronic renal disease, Cyanotic heart disease, Hemoglobinopathies.
• Environmental factors: Alcohol, Smoking (leads to early pregnancy loss), Caffeine
• Exposure to radiation: (> 5 rads) and anesthetic gases.
• Endocrine problems: Luteal phase defect (deficiency of progesterone), Thyroid abnormalities – hypothyroidism, Poorly controlled diabetes mellitus, PCOD, Hyperprolactinemia
• Immunological causes: Antiphospholipid antibody syndrome (APLA syndrome), Inherited thrombophilias
• Uterine factors like Cervical incompetence (M/C 2nd trimester), Mullerian anomalies (M/C associated with abortions is the septate uterus), Large and multiple submucous leiomyomas, Asherman syndrome, DES exposure in utero.
• Weight of mother: Underweight or nutritional deficiency does not lead to abortion, Obesity leads to abortion.
• Others: Trauma, Subchorionic hematoma Defective placentation.

Paternal factors: Increased paternal age is associated with increased abortion.

Ans.A. Incompetent os
The most common cause of second-trimester pregnancy loss is cervical incompetence, in which the patient presents with recurrent painless abortion.
Causes of abortion
Fetal factors: 

• Chromosomal abnormalities (M/C cause).
• Hydropic degeneration of villi.
• twin/multiple pregnancies.

Maternal factors

• Maternal infections: TORCH infections, Malaria, Ureaplasma, Chlamydia, Brucella, Spirochaetes.
• Maternal medical disorders: Hypertension, Chronic renal disease, Cyanotic heart disease, Hemoglobinopathies.
• Environmental factors: Alcohol, Smoking (leads to early pregnancy loss), Caffeine.
• Exposure to radiation: (> 5 rads) and anesthetic gases.
• Endocrine problems: Luteal phase defect (deficiency of progesterone), Thyroid abnormalities – hypothyroidism, Poorly controlled diabetes mellitus, PCOD, Hyperprolactinemia.
• Immunological causes: Antiphospholipid antibody syndrome (APLA syndrome), Inherited thrombophilias.
• Uterine factors like Cervical incompetence (M/C 2nd trimester), Mullerian anomalies (M/C associated with abortions is the septate uterus), Large and multiple submucous leiomyomas, Asherman syndrome, DES exposure in utero.
• Weight of mother: Underweight or nutritional deficiency does not lead to abortion, Obesity leads to abortion.
• Others: Trauma, Subchorionic hematoma Defective placentation.

Paternal factors: Increased paternal age is associated with increased abortion.