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Androgen insensitivity syndrome
Hypospadias and epispadias
Benign prostatic hyperplasia
Male hypoactive sexual desire disorder
Premature ovarian failure
Polycystic ovary syndrome
Sex cord-gonadal stromal tumor
Surface epithelial-stromal tumor
Germ cell ovarian tumor
Pelvic inflammatory disease
Female sexual interest and arousal disorder
Genito-pelvic pain and penetration disorder
Fibrocystic breast changes
Paget disease of the breast
Preeclampsia & eclampsia
Intrauterine growth restriction
Congenital cytomegalovirus (NORD)
Neonatal herpes simplex
Congenital rubella syndrome
Gestational trophoblastic disease
Fetal hydantoin syndrome
Fetal alcohol syndrome
Disorders of sex chromosomes: Pathology review
Prostate disorders and cancer: Pathology review
Testicular tumors: Pathology review
Uterine disorders: Pathology review
Ovarian cysts and tumors: Pathology review
Cervical cancer: Pathology review
Vaginal and vulvar disorders: Pathology review
Benign breast conditions: Pathology review
Breast cancer: Pathology review
Complications during pregnancy: Pathology review
Congenital TORCH infections: Pathology review
Disorders of sexual development and sex hormones: Pathology review
Amenorrhea: Pathology Review
Testicular and scrotal conditions: Pathology review
Sexually transmitted infections: Warts and ulcers: Pathology review
Sexually transmitted infections: Vaginitis and cervicitis: Pathology review
HIV and AIDS: Pathology review
Penile conditions: Pathology review
0 / 18 complete
0 / 2 complete
antiphospholipid syndrome p. 480
fibroid tumors p. 665
Listeria monocytogenes p. , 137
syphilis p. 181
Vitamin A excess p. 638
warfarin p. 638
Sam Gillespie, BSc
Tanner Marshall, MS
Pauline Rowsome, BSc (Hons)
A miscarriage, or spontaneous abortion, is defined as a pregnancy loss that occurs without outside intervention before the 20th week of pregnancy.
Pregnancy is so complex that there are many different ways for the process to get off course and for a miscarriage to occur.
For example, if there’s a chromosomal abnormality in the sperm or egg then the resulting zygote will have a problem.
One of these problems is called aneuploidy, which is when there are missing chromosomes or additional chromosomes.
For example, if there’s one member of a chromosome pair missing, that results in 45 chromosomes total, instead of the normal 46, it’s called a monosomy.
And if there’s one extra chromosome joining a pair, that results in 47 chromosomes total, and it’s called a trisomy.
Some types of aneuploidy are viable like Turner’s syndrome or Down syndrome, whereas many are not and lead to a miscarriage.
Another abnormality is polyploidy, and that’s when a zygote receives more than one set of 23 chromosomes from either the sperm or egg, resulting in three sets, totaling 69 chromosomes, or even four sets, totaling 92 chromosomes.
Polyploidy is generally not viable and leads to a miscarriage.
One more abnormality is a translocation.
It can either be balanced, where two nonhomologous chromosomes essentially trade equal amounts of DNA, or unbalanced, where the chromosomes exchange unequal amounts of DNA, resulting in either too many or too few copies of certain genes on the involved chromosomes.
Now even if a parent carries a balanced translocation, the sperm or egg may end up with an unbalanced translocation, and the zygote won’t have a normal number of genes.
Some translocations are viable, whereas many are not, and can lead to a miscarriage.
Now, let’s say that there are a normal number of chromosomes present, and that the zygote becomes a blastocyst and tries to implant, there are still many ways in which a miscarriage can occur.
First if the blastocyst fails to implant into the endometrial lining of the uterus, then it won’t find a blood supply and stops growing and get reabsorbed.
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