[AKA_Monet]

First off, I have never been pregnant, so I cannot fathom what actually happens when one becomes pregnant.

Second, I am only a lowly Ph.D. research scientist that studies molecular genetics and cardiovascular biology--genes and chromosomes... So, I do not have the utmost expertise in the area of reproductive biology as it relates to the human female other than what I experience on a monthly basis.

However, as I understand it:

A ovulation and menstruation may not necessarily be tied together genetically... You can do the Entrez-PubMed search if you would like...

There are at least 10 different hormones a "normal" ovulating female who is NOT on birth control pills or any other reproductive or hormonal medication. Of those, the important ones regulating both ovulation and menstruation are:

Estrogen--increases while not menstruating
Progesterone--peaks during menstruation--and relative increases during pregnancy
Testosterone--not just for men anymore--plays a significant role in ovulation
FSH--follicle stimulating hormone--acts early during ovulation
LSH--Lutienizing stimulating hormone--acts toward the end of ovulation tract
and Gonadotropin--acts on many different levels

Some pregnant women have a regular period, as if it on the latter days of the menstruation cycle--the regular Always pads--not the Always with wings Super overnights for used for daytime 'cuz a period is chunckily horrendous with migraines and evil attitudes... Then the period wanes as the pregnancy continues...

Some women are spotty thru out their pregnancy and use the pantyliners...

Some women are the textbook example of a pregnancy...

Every woman varies during her pregnancy and that may be genetically predisposed. Most the time, a woman's reproductive cycle is similar to that of her mothers--including the fibroids and hysterectomies.

Women who get pregnant on the pill usually are taking them incorrectly, however, there is evidence that ovulation can be irregular in some women and these women constantly ovulate even while taking a low dosage estrogen analogs. High dosage estrogen analogs taken correctly typically turn off the ovulation schedule.

Moreover, some antibiotics interfere with the effectiveness of the pill. Meaning the estrogen analog cannot turn off the ovulation schedule because the antibiotic drug is in the way--to explain it colloquially. One antibiotic is tetracycline and its analog drugs.

If a woman becomes pregnant while on estrogen analogs, it may severely harm the fetus. The child that is born can have birth defects--the baby's skull does not form--anencephalopathy. That is why most drug manufacturer's recommend a doctor's consult if a woman suspects pregnancy while on the pill.

What happens while a "normal" woman who has regular monthly menstruation, the estrogen analog is really high--for some breast cancer researcher it is too high. When a woman stops the estrogen analog, it is like a complete drop in that hormone. What the body does is try to compensate all month long with all the other 10+ hormones that cycle regularly--one being progesterone. When the estrogen analog drops, progesterone sky-rockets up and that signals to the uterine wall, the endometrium, to slough off--hence, causing menstruation.

So in essence, the young lady described as to not taking the white pills and has UNPROTECTED intercourse with a man, is most likely NOT to be impregnated. Typically, for most women, it takes 5-14 days for the FULL estrogen analog effects to wear off in the body. But it differs from woman to woman.

Typically, a woman may be unable to become pregnant during her menstruation, especially if she is taking the pill. However, there are cases of several women getting pregnant while menstruating... PM me if you have questions...

How a spontaneous abortion (miscarriage) occurs is not well understood. It is thought that a severe genetic abnormality can trigger a miscarriage--like instead of a normal 4 celled embryo, one has a 5 celled embryo. There may be toxic substances or necrotic (dead) material on the endometrium.

ABO Blood groupings and Rh factors have nothing to do with the propensity to become pregnant. If anyone has that kind of conceptualization, then I suggest that this person goes on the Maury Povich show and get the DNA test required...