Note: I originally had this as a question, but I guess it was too long, so I'm re-posting this in an article.

Question number one: Vampires hearts don't beat, correct? Correct. I believe this is mentioned several times. Now, in health class, they teach you that your heart pumps and makes your blood flow, correct? Correct. So, it stands to reason that, since vampires hearts don't beat, they don't have blood flow, correct? Yes. So, they have no blood flow, no circulation. They cannot bleed, or blush, or anything related to circulation, yes? Yes. This is said several times in the book.

Now, call me crazy, but don't chemicals and blood flow cause erections?

Most people know that erections are caused by the flow of blood into the three chambers of the penis. The corpora cavernosa are two columns of spongy tissue that make up 90 percent of the erectile tissue of the penis. The corpus spongiosum surround the urethra and holds only about 10 percent of the blood present in the penis during erection.
During arousal, the smooth muscles lining the veins of the arteries begin to relax. This relaxation causes blood to flow in. The veins of the penis begin to constrict; thus, blood can get in much more easily then it can out. The penis can hold 10 times the amount of blood when it is erect as opposed to when it is not erect. After orgasm, the veins and arteries return to normal and the blood flow returns to normal. Prostate cancer treatments can affect the flow of blood into the penis. Prostatectomy has been known to divert the flow of blood into the penis while radiation treatment has been known to cause arteriosclerosis, which is the hardening of the arteries.
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So, Edward doesn't have circulation, no blood flow. He does not have a working heart to pump blood through his body, much less to his penis. So, how does he get an erection?

Question number two: Through the entire series, Smeyer/Bella put an emphasis on how cold Edward is. When they are laying together, Bella is wrapped up in a blanket, to keep her body warm while laying next to the frozen Edward, yes? In Eclipse, when they are in the tent, Jacob comes in and lays with Bella to keep her warm because Edward can't. Because he's so cold.

So, it stands to reason that all of Edward's body is an icicle, yes? So, since he can't lay with Bella on a couch with her clothes on because he's afraid she'll freeze, how do they manage to have sex? No, think about it! He's an icicle, frozen. His freezing cold, naked body is pressed against Bella's naked body. How does she not freeze?

Also, since his entire body is freezing, it stands to reason that his penis would be too. Even if he MAGICALLY managed to get an erection, it would be freezing cold. Wouldn't that be similar to sticking a Popsicle into her vagina? I can't imagine that would be too pleasurable, so, how does she stand it?

Question number three: Jasper has the scars from when he was turned into a vampire. Esme still has the left over pregnancy fat from when she was pregnant. This carried over with them when they are changed, yes? So why does Bella, who was torn open from the inside out, have no scars nor a gaping hole in her tummy?

Question number four: How does having too many chromosomes create super creatures?

Chromosomal abnormalities usually result from an error that occurs when an egg or sperm cell develops. It is not known why these errors occur. As far as we know, nothing that a parent does or doesn’t do before or during pregnancy can cause a chromosomal abnormality in his or her child.
Egg and sperm cells each contain 23 chromosomes. When they join together, they form a fertilized egg with 46 chromosomes. But sometimes something goes wrong before fertilization. An egg or sperm cell may divide incorrectly, resulting in an egg or sperm cell with too many or too few chromosomes.
When this cell with the wrong number of chromosomes joins with a normal egg or sperm cell, the resulting embryo has a chromosomal abnormality. A common type of chromosomal abnormality is called a trisomy. This means that an individual has three copies of a specific chromosome, instead of two. For example, individuals with Down syndrome generally have three copies of chromosome 21 (though a small number of cases are caused by chromosomal rearrangements).
In most cases, an embryo with the wrong number of chromosomes does not survive. In such cases, the pregnant woman has a miscarriage. This often happens very early in pregnancy, before a woman may realize she’s pregnant. More than 50 percent of first-trimester miscarriages are caused by chromosomal abnormalities in the embryo (1).
Other errors can occur before fertilization. These errors can alter the structure of one or more chromosomes. Individuals with structural chromosomal abnormalities usually have the normal number of chromosomes. However, small pieces of a chromosome (or chromosomes) may be deleted, duplicated, inverted, misplaced or exchanged with part of another chromosome. These structural rearrangements may have no effect on a person if all of the chromosome is there but just rearranged. In other cases, the rearrangements may result in pregnancy loss or birth defects.
Errors in cell division can occur soon after fertilization. This can result in mosaicism, a condition in which an individual has cells with different genetic makeups. For example, individuals with the mosaic form of Turner syndrome are missing an X chromosome in some, but not all, of their cells. Some individuals with chromosomal mosaicism may be mildly affected, but the severity of the condition depends largely on the percentage of abnormal cells.
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According to every doctor ever, too many chromosomes create problems, not cool superpowers.

Note: I know it's fiction, and Smeyer can bend the laws of human health to fit her story, but I know a lot of babies who have chromosomal problems. To me, it seems like she's making light of these issues. There is nothing “extraordinary” about having a baby with too many chromosomes. It does not give them superpowers and this was something that was easily researched. Hell, she could have just used the phrase “magic” and no one would have thought twice.