The First Trimester: Weeks 1 - 12

Bleeding in Early Pregnancy

Most couples expect to get pregnant at some point, and when they do for the first time it suddenly dawns on them what a gamble pregnancy actually is. One of the most frightening things is to experience bleeding in the first part of the pregnancy. Termed "first trimester bleeding," it is any bleeding noted during the first twelve weeks, and it is one of the most common symptoms to send a woman to her obstetrician.

No bleeding in early pregnancy is to be considered normal--that's the bad news. But the good news is that most of the time it's caused by something fairly harmless--cervicitis. This is a condition in which the delicate cells at the mouth of the womb (cervix) can bleed due to the mechanical action of intercourse, the alteration of acidity in the vagina (pH), or the effects of infections on these cells. With the hormonal changes of pregnancy, the fragile internal cells peek out a bit onto the external portion of the cervix, which is a harsher environment for them. Normally nestled more deeply away from sexual activity, now they can be battered. They're easily damaged, causing bleeding. Of course, we're not talking about a whole lot of bleeding here--merely what is perceived as spotting. It must also be noted that these cells usually don't bleed with sex--usually there is a predisposing condition, like cervicitis.

Cervicitis is inflammation due to infection. Yeast is the most common culprit, and a simple prescription or even over-the-counter cream can end this concern quickly. Other infections are more worrisome. Sexually transmitted diseases (STDs), like gonorrhea, chlamydia, trichomonas, and Gardnerella can do the same, so a microscopic evaluation is the best approach rather than just assuming it's yeast.

Some infections may be silent for years, meaning that even though there is no question of fidelity in a couple, still there may have been an infection long before they even met each other. Therefore cultures for STDs has become standard in all pregnancies. Harmless small polyps can cause bleeding also. If these can't be gently and painlessly twisted off during a physical exam, then they're usually destroyed by the very act of delivering the baby.

Sometimes a small piece of tissue becomes loose and disintegrates through some unknown cause, causing spotting. It's usually an hormonally stimulated collection of menstrual-like tissue that can often be confused with a miscarriage. If it's just tissue debris, it can mean nothing. If it's actual tissue of the pregnancy (fetal or placental), then there should be serious concern.

Although the above instances describe the causes of bleeding that do not indicate miscarriage, still miscarriage should be ruled out when there's any bleeding. And when one considers that the cramping of a threatened miscarriage can feel exactly like the growing pains of a normal uterus, we obstetricians are fortunate to have other tools to give a patient (and her doctor) peace of mind. Blood tests can prove that the pregnancy hormone is increasing as expected, which confirms a healthy pregnancy, and ultrasound can demonstrate the physical well- being of a growing baby by showing a healthy heart rate or by ruling out an ectopic (tubal) pregnancy.

It's true that miscarriage is a fact of life as we know it, and usually it's due to some sort of doomed genetic mismatch; but although most miscarriages begin with first trimester bleeding, first trimester bleeding isn't always indicative of a miscarriage. But we always respect first trimester bleeding until we can determine the cause. Usually it has a good outcome. So although it's understandable how first trimester bleeding can cause a couple a lot of anxiety and worry, we can usually find something unrelated to the pregnancy--and treatable--to blame it on.

Other Bleeding in Pregnancy, Including Ectopic Pregnancy

No bleeding in pregnancy should be ignored. But there are harmless reasons to have bleeding as well as extremely dangerous reasons. In the later trimesters, disruption of the placenta--premature separation of the placenta away from the uterine wall--can cause massive hemorrhage that threatens not only the baby, but the mother as well! This is a true obstetrical emergency. Premature dilation of the cervix can cause a "bloody show" that warrants intervention so as to stop a premature delivery.

At mid-pregnancy, an incompetent cervix (from previous abortions, D & Cs, or congenital weakness) can cause a painless dilation of the cervix with spotting sometimes the only warning signal. p> At very early pregnancy, a threatened miscarriage will present as bleeding, as will an abnormally low progesterone. (It is still unclear whether the baby is threatened because the progesterone is low or whether the progesterone is low because the baby is threatened.)

Cervical polyps, delicate benign overgrowths of internal cervical cells that protrude into the vagina, often present for the first time because the increased estrogen of pregnancy will make them grow suddenly into noticeable size. A cervical polyp will get banged around with intercourse or even with just walking, and bleed. They can be twisted off in the office if on a narrow stalk, or watched until delivery during which a passing baby will destroy them (baby vs. polyp--baby wins!).

An extremely dangerous condition, ectopic pregnancyis nothing more than a pregnancy that didn't land in the uterus where it belongs. Migration of a fertilized egg may get hung up in the tube due to old scarring from infection, surgery (putting tubes back together after a tubal ligation), or even endometriosis. Ectopics can be growing pregnancies not only in the delicate tube, but in other areas that will not expand to accommodate like the uterus will. The wall of the uterus, near the ovary, even in the abdomen are ectopic sites, and they're all pretty much doomed. The fallopian tube, however, remains the most frequent site for ectopic pregnancies.

A structure stretched to its limits by an expanding pregnancy will ultimately rupture, tearing blood vessels that supply that structure--blood vessels that have become larger due to the pregnancy. Often the internal bleeding is enough to cause a collection of blood in the abdomen (hemoperitoneum). Surgery can be either by laparoscopy or by a regular incision, during which the blood is evacuated, the bleeding sites secured, and the ectopic suctioned or scooped away.

If a patient is fortunate (unfortunate) enough to have an ectopic diagnosed before rupture, she may be a candidate for methotrexate, which is a cancer chemotherapy drug known to be fetocidal. If she doesn't meet criteria for methotrexate, she can undergo a laparoscopy wherein a slit is made over the top of the tube (linear salpingostomy) and the ectopic suctioned away. This may be done as an outpatient if there's been no rupture or melodrama.

All ectopic pregnancies must be dealt with. The Catholic Church has no objection to removing ectopic pregnancies, as it is felt that one is treating the mother for a condition that can be lethal. It does not consider it an abortion.

If a woman has had one ectopic, she isn't automatically going to have another, even though the condition that provoked the first ectopic is still there. But...she is at increased risk over those women without a previous ectopic history. A repeat ectopic on the same tube warrants removal of that tube, though. Common sense prevails.

Nausea and Vomiting in Pregnancy

There are several symptoms that may make a woman suspect she's pregnant:

  • Breast tenderness, due to stimulation of breast tissue by estrogen;
  • Loss of usual figure, even before any weight is gained, which is also a hormonal effect;
  • Constipation, due to progesterone slowing down the intestinal tract;
  • Cravings, due to, don't have this one entirely nailed down yet.
  • Mood swings, also hormonal.
  • Queasiness and nausea, due, many theorize to the rise in the pregnancy hormone hCG, which is resembles at a microscopic level thyroid hormone, the elevation of which can cause nausea.


Nothing is as miserable in early pregnancy as the severe nausea that can happen. True, many are blessed with no nausea whatsoever, but many suffer greatly, even to a point wherein they need to be hospitalized overnight to be rehydrated with IV solutions. When nausea is this bad, we refer to it as hyperemesis.

Nausea causes dehydration, dehydration worsens the nausea, and further nausea causes further dehydration. A vicious cycle can be broken with a simple IV overnight to rehydrate. Often this is enough to get a woman stable enough to begin eating again.

Usually when the amount of rising hCG plateaus (at about 12 weeks), the nausea subsides. There are exceptions, with lingerings into the second trimester, but by this time the nausea is much more tolerable.

Until recently, hyperemesis was a chauvinistic stigma. Obstetricians (mostly men) would say, advise, and even report in textbooks that it was attention seeking on the part of some women who had personal problems at home or with their husbands. This ridiculous and misogynistic explanation is no longer used. (Of course, perhaps a pregnant woman threw up on the author of said textbook and his attention.)

There are some who feel that this unglamorous aspect of pregnancy has survival value for our species--historically, anyway. Aversions to certain foods may have kept our race going back in times when eating certain things would be harmful. And of course, aversions are also closely related to cravings, the opposite swing of the avoiding bad things/seeking good things pendulum. (Were pickles important in early woman?)

Bendectin, with two ingredients, including vitamin B6, was used up until the eighties for nausea of pregnancy until it was voluntarily withdrawn from the market because of legal costs in defending this drug when it was accused of causing birth defects. The studies, however, proved the amount of defects was no greater in Bendectin users than non-Bendectin users. Unfortunately, a supermarket tabloid picked out incidents wherein a mother with a handicapped child had used Bendectin (and milk, and nailpolish, and prenatal vitamins, I suspect also), and the rest was frenzied medicolegal history.

Today, when there is weight loss and even hospitalization doesn't mitigate the nausea, and after hyperthyroidism is ruled out (mandatory), obstetricians consult a gastroenterologist to rule out dysentery, parasites, and other exotic causes. When all is said and done, they recommend, separately, of all things, the idividual ingredients of the old Bendectin. Of course, there are big gun drugs by prescription, but these are reserved for the most severe cases.

There are few feelings as bad as the helplessness of nausea, but--and I'll tell you a little OB-GYN secret--we obstetricians find reassurance in this misery, because it means the hormones are raging and the pregnancy is strong. The miscarriage chances are very small when there's nausea in pregnancy. A mixed blessing, for sure. But the end really does justify the means.

For more information on fetal development check out our pregnancy videos.

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