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Infertility, Pregnancy, and Childbirth
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Pregnancy and Childbirth

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Erythromycin and Pyloric Stenosis

A study published in the July 2002 issue of the Archives of Pediatrics and Adolescent Medicine confirms suspicions that a common antibiotic can cause a serious condition in very young infants.

Infantile hypertrophic pyloric stenosis (IHPS) occurs when the muscle surrounding the outlet from the stomach becomes overgrown and obstructs the passage of food into the intestines. The condition, which usually arises in the first three to five weeks of life, causes projectile vomiting. This can lead to dehydration, weight loss, and electrolyte imbalances that affect kidney function. Physicians have long believed that exposure to the antibiotic erythromycin is related to the condition.

To investigate the link, researchers tracked the antibiotic use and IHPS occurrence in over 314,000 infants between 1985 and 1997. Of the 7,138 infants given prescriptions for erythromycin within the first 90 days of life, 804 were diagnosed with pyloric stenosis. Further analysis showed that while infants younger than two weeks old were rarely given erythromycin, those who were exposed within the first two weeks of life were eight times as likely to develop IHPS as an infant who had not received the drug during this time. Babies who received erythromycin after the first two weeks did not appear to have an increased risk for the condition.

Physicians commonly use erythromycin to treat infants with illnesses such as respiratory and ear infections, whooping cough, and conjunctivitis. The results of this study suggest the risks and benefits of erythromycin need to be carefully weighed — and perhaps other antibiotics tried — before it is prescribed for use in infants younger than two weeks.

October 2002 Update

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The Benefit of Magnesium for Preeclampsia

Eclampsia and preeclampsia are the leading causes of death for pregnant women and their fetuses, particularly in developing countries. Physicians believe the high blood pressure, swelling, and protein in the urine associated with preeclampsia lead to the convulsions and coma of eclampsia.

Obstetricians generally use anticonvulsants to treat and prevent the convulsions of eclampsia. In the U.S., magnesium sulfate has been the drug of choice for nearly a century. Research confirms magnesium as the most effective drug at preventing eclamptic seizures. Now magnesium sulfate is being used increasingly to treat preeclampsia as well, with the hope it will prevent eclampsia. A study published in the June 1, 2002, issue of The Lancet confirms this hope.

The study, dubbed the Magpie Trial, was a large international effort aimed at discovering the effects of magnesium sulfate on women with preeclampsia and their children. Close to 10,000 women with preeclampsia from 33 developed and developing countries were involved. Roughly half of the women were randomly assigned to receive magnesium sulfate while the other half received a placebo.

Use of magnesium sulfate resulted in a 58% decrease in risk of eclampsia compared to use of the placebo. This translates to 11 fewer women in 1,000 suffering from eclampsia. The preventive effect of magnesium was consistent regardless of the severity of the preeclampsia, the stage of pregnancy, whether an anticonvulsant had been given prior to the trial, and whether the woman had delivered before entry into the trial. Women receiving magnesium sulfate also had a 45% lower risk of death than women receiving the placebo. There appeared to be no difference in the risk of fetal or infant death related to the use of either the drug or the placebo. However, women receiving magnesium sulfate had a 27% lower risk of premature detachment of the placenta.

While the benefits of using magnesium sulfate are evident, some non-serious negative side effects were also apparent. Roughly 25% of the women receiving the drug experienced flushing, nausea, or vomiting. Only 5% of the women receiving the placebo experienced side effects.

Based on the results of this study, magnesium sulfate may become a mainstay in the treatment for preeclampsia as well as eclampsia. The low cost of the drug makes this even more likely, not only in the U.S., but also around the world.

September 2002 Update

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Repeat Cesareans Best

Many women who deliver their first baby through cesarean section have trouble deciding whether to use the same method to deliver a second child. Some women have to balance their desire for a natural birth experience with the risk to the baby presented by vaginal delivery. Researchers now say that a second cesarean section is the safest childbirth method for women who have already had one.

In cesarean sections, babies are delivered through surgical openings in the uterus and lower abdomen. Vaginal deliveries after cesareans can be dangerous because the labor and birth could rupture the scars and uterus, possibly depriving the baby of oxygen and causing severe blood loss in the mother.

A study of 313,238 births in Scotland found that for women with previous cesareans, the delivery-related death rate for subsequent babies was about 11 times higher in vaginal births than in planned repeat cesareans. The study involved babies born between 37 weeks' and 43 weeks' gestation and appears in the May 22/29, 2002, Journal of the American Medical Association.

Still, the overall infant death rate for vaginal births after a prior cesarean delivery (VBAC) was about equal to the death rate in first-time vaginal births — about 12.9 per 10,000 babies, lower than previously thought. But the infant death rate associated with planned repeat cesareans was only 1.1 per 10,000.

Current guidelines recommend limiting VBACs to full-term babies in the headfirst position, those born to women with only one previous cesarean that was done with a low horizontal incision (vertical scars put the baby at higher risk than horizontal ones), and an otherwise healthy pregnancy.

While many insurers have sanctioned VBACs to cut costs and reduce hospital stays, some doctors remain wary. However, it is ultimately up to the patient — the International Federation of Gynecology and Obstetrics and the American College of Obstetricians and Gynecologists say that the patient should decide on method of delivery. This, of course, after the patient is advised on all risks and benefits of both procedures.

July 2002 Update

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In-vitro fertilization may cause birth defects, low birth weight

It's been 24 years since the first baby was conceived with the help of in-vitro fertilization (IVF), bringing hope to thousands of childless couples. In 1999 alone, over 30,000 babies were born in America with the help of artificial reproductive technologies (ART), including IVF. Since then, an estimated 300,000 IVF babies have been born worldwide. But this revolutionary way to overcome infertility is not risk-free. Two new studies published in the March 7, 2002, issue of the New England Journal of Medicine suggest that ART babies are more likely to be born with birth defects and low birth weights than newborns conceived naturally.

In IVF the man's sperm and the women's egg are combined in a laboratory dish. After fertilization, the resulting embryo is then transferred to the women's uterus to develop naturally. A special IVF procedure called intracytoplasmic sperm injection (ICSI), where the sperm is injected directly into the egg, can also be used for severe male infertility.

ARTs, including IVF, increase the risk of multiple births because several embryos are usually transferred to the uterus at one time to increase the probability of a successful pregnancy. But this practice is controversial because multiple births are associated with low birth weight, which puts the newborn at an increased risk for short- and long-term disabilities and even death. However, in one of the new studies, researchers with the U.S. Centers for Disease Control found that even ART babies born alone were 2.6 times as likely to have a low birth weight than a naturally conceived single infant.

In the other study, Australian researchers found that about 9% of the 301 IVF babies studied had birth defects, such as heart trouble, stunted limbs, Down syndrome, and cleft palate, compared to only 4.2% of the 4,000 naturally conceived babies studied. The risk was still more than doubled when multiple births were not considered.

Neither these nor previous studies have been able to identify whether the reason for the excess risk of low birth weight and birth defects is related to the underlying infertility itself or to the procedures and drugs used to overcome it.

To many advocates of assisted reproduction, the results of these studies aren't necessarily frightening, but reassuring. They look at them and celebrate that more than 90% of IVF babies are born healthy. But regardless of the interpretation of the numbers, couples looking for help with fertility should consider these risks.

May 2002 Update

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Timing of pregnancy tests affects accuracy

Pregnancy test instructions routinely approve testing "as early as the first day of the missed period." However, a recent study suggests such guidance could lead to inaccurate results.

Researchers in North Carolina evaluated the number of pregnancies that were actually detectable on the first day of a woman's missed period. The participants, women ages 21–42, were planning to conceive. Of the pregnancies conceived during the five-year study, 10% of the fertilized eggs had not yet implanted in the woman's uterus on the day a period was expected. Even one week after the first day of the missed period, the test was only accurate 97% of the time.

In addition, due to natural fluctuation in the schedule of ovulation, implantation does not necessarily occur before a woman's regular period should. The timing of implantation varies widely in its relation to the expected period. Many women will test positive a week or more before their period is expected, while some will test positive only a week or more afterward. As a result, women should avoid substances known to harm a fetus (cigarette smoke, large quantities of alcohol) if they are trying to conceive, even if a pregnancy test comes back negative on the first day of a missed period.
March 2002 Update

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Birth Control Patch

The first skin patch approved for birth control by the U.S. Food and Drug Administration will be available by prescription in 2002. Ortho Evra works by slowly releasing progestin and estrogen, the same hormones used in birth control pills, into the bloodstream. Its efficacy lies in the prevention of ovulation and the thickening of the cervical mucus, which makes it harder for sperm to enter the uterus.

Ortho Evra is 99% effective in preventing pregnancy. However, the side effects include an increased risk of blood clots, heart attack, and stroke. This risk is even higher for cigarette smokers. In three clinical trials involving over 3,000 women taking Ortho Evra, 5% of participants had at least one patch that detached from their skin and 2% withdrew from the trial due to skin irritation. Also, the patch appeared to be less effective in women weighing more than 198 pounds.

The regimen is similar to that of birth control pills. The patch is changed once a week for three weeks. The patch-free fourth week allows for a menstrual period. The small (less than two square inches) and paper-thin design makes Ortho Evra easy to hide beneath clothing. It can be applied to the buttocks, abdomen, upper torso (front or back), and the upper outer arm, and be worn in a different place each week.
February 2002 Update

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Pregnancy and Anticonvulsant Drugs

"Do you have epilepsy or take any anticonvulsant drugs?" This is a common question asked of pregnant women and women who are planning to become pregnant. The cause for the concern is the risk of birth defects associated with the disease. But whether birth defects are related to the mother's epilepsy or caused by the drugs used to treat it remained unknown until recently.

A study published in the New England Journal of Medicine examined newborns for birth defects related to anticonvulsant drugs. Each newborn belonged to one of three groups: newborns exposed to anticonvulsant drugs in the womb; newborns of mothers with epilepsy who did not take anticonvulsant drugs; and newborns of mothers without epilepsy or a history of seizures. Results showed birth defects were more frequent in infants exposed to anticonvulsant drugs (20% of infants exposed to one drug had birth defects and 28% of infants exposed to two or more drugs had birth defects). However, the infants of mothers with epilepsy who were not treated with anticonvulsant drugs were at no greater risk of birth defects then infants of mothers without epilepsy.

This study suggests birth defects are caused by anticonvulsant drugs and not by epilepsy itself. A separate, earlier study based on data from a number of different countries identified the types of birth defects associated with common anticonvulsant drugs. Some of these findings are summarized below:

Birth Defect Related Anticonvulsant Drug
Spina bifida Valproic acid
Oral clefts Phenobarbital or methylphenobarbital
Heart defects Phenobarbital, methylphenobarbital, valproic acid, or carbamazepine
Brain and face abnormalities, shortened limbs Valproic acid

If you take anticonvulsant drugs and are pregnant, or are thinking of becoming pregnant, consult your physician about the risks to your baby.
November 2001 Update

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Vaccine safety: no link between thimerosal and neurodevelopmental disorders

Parents should feel confident and safe when having their children immunized. No evidence exists that proves a link between thimerosal-containing vaccines and neurodevelopemental disorders, such as autism, attention deficit-hyperactivity disorder, or speech and language delay. The Institute of Medicine recently reported these findings, consistent with the recommendations of the American Academy of Pediatrics.

Thimerosal, a mercury-containing preservative, was used for many years in vaccines to prevent contamination. Taking in a high dose of mercury is toxic to the human nervous system. But because of the increasing number of vaccines routinely recommended for infants, concern was raised in 1999 by the Food and Drug Administration that the total amount of mercury contained in the vaccinations could be exceeding the recommended mercury levels for infants.

Although there's no data to suggest thimerosal caused any harm, the American Academy of Pediatrics and the U.S. Public Health Service have requested manufacturers remove thimerosal from vaccines. As a result, most, if not all, childhood vaccines are now thimerosal-free.

The Institute of Medicine's recommendations emphasized the importance and continued safety of childhood vaccination. Parents should definitely be reassured that all routine childhood immunizations are in their children's best interests, as they clearly have been shown to prevent potentially life-threatening diseases.
November 2001 Update

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Childhood Depression and Postpartum Psychiatric Depressive

In the United States, more than 2 million adults suffer from bipolar manic depressive disorder, an illness of extreme moods. It is characterized by deep depression followed by periods of hyperactivity and elation, referred to as mania, with periods of normal mood in between. Bipolar disorder often leads to substance abuse and one in four people with the condition attempt suicide.

In a recent study published in the American Journal of Psychiatry, researchers set out to determine how often major childhood depression turns into bipolar disorder. The researchers followed up on 72 subjects who, at an average age of 10.3 years, had been treated for major depressive disorder with the tricyclic antidepressant drug nortriptyline. They also studied 28 normal subjects.

At the time of follow-up, the average age of the subjects who had had prepubertal major depressive disorder was 20.7 years. Of these subjects, 33.3% now had bipolar disorder, compared to none of the normal comparison subjects.

These results may, in part, be due to heredity. A large portion of the prepubertal children who had been diagnosed with a major depressive disorder had family histories of bipolar disorder. Because bipolar disorder tends to run in families, these children may have been more vulnerable to developing the condition. Another possibility is that the children who were originally treated with nortriptyline already had bipolar disorder, but had not yet experienced their first manic episode.

Clinicians treating children with antidepressants should be aware of the risk that children with major depressive disorder may develop adult bipolar manic depressive disease.

Another study, published in Psychology and Medicine, sought to determine the long-term prognosis of women with postpartum psychiatric disorders. 50-80% of women experience some degree of postpartum depression within one month of delivering a child. Postpartum psychiatric disorders are more extreme.

The study authors used standardized questionnaires to determine the long-term outcome of 64 women who had been hospitalized with postpartum psychiatric disorders 23 years earlier, and who had been interviewed for a 1982 study of women with diagnoses of schizophrenia, schizo-affective, bipolar, or unipolar affective disorders.

The researchers found that 75% of the women had recurrent psychiatric illness, and 37% of the women had at least three subsequent episodes. However, only 29% of the 34 women who gave birth after the initial postpartum psychiatric disorder had additional episodes of maternal psychiatric illness. In addition, a majority of the 64 women were functioning well in society; 71-73% were employed and in stable relationships.

The women with the best outcomes were those who had an initial diagnosis of unipolar disorder, those who experienced psychiatric illness after a first pregnancy, and those whose psychiatric illness started within one month of delivery.
July 2001 Update

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New IUD

Women have a new choice for birth control. Late last year the FDA approved the intrauterine device (IUD) Mirena. Mirena is a T-shaped plastic device placed in the uterus by a physician that releases small amounts of the hormone levonorgesterel to block conception. Although not the first hormonal IUD, Mirena only needs to be replaced once every five years. The others, in contrast, must be changed yearly. The manufacturer, Berlex Laboratories, reports less than 1% of women become pregnant while using Mirena.

Physicians can easily remove the IUD. And once it’s extracted, a woman can again become pregnant. According to Berlex, eight out of ten women who are trying to conceive will become pregnant within the first year after Mirena is removed.

Mirena is not for everyone, however. Women with a history of pelvic inflammatory disease or a previous ectopic pregnancy (when the embryo grows outside the uterus) should not use IUDs. Furthermore, they don’t protect against sexually transmitted diseases. Possible side effects include spotting or missed periods.
June 2001 Update

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Ginger for Morning Sickness

A new study suggests using ginger to relieve morning sickness may not just be an old wives tale.

Researchers in Thailand recently evaluated the effectiveness of ginger (Zingiber offinale) to alleviate nausea and vomiting during pregnancy. A similar study had previously found the root helped pregnant women suffering from severe morning sickness requiring hospitalization. But this severe condition, called hyperemesis gravidarum, only occurs in approximately 0.3% of pregnancies. In contrast, milder nausea affects up to 85% of pregnant women and about half experience vomiting. It’s caused, in part, by rising levels of the hormone estrogen during the first 3 months of pregnancy.

The study involved 70 pregnant women reporting nausea and vomiting. Three times a day for four days, 32 of the women were given 250mg capsules of fresh ginger that was chopped into pieces, then baked and ground into powder. The remainder received a placebo. All of the women were advised not to take other drugs.

The number of vomiting episodes decreased significantly for the women taking ginger compared to the placebo group. Using two other scales, the researchers also found the frequency of nausea symptoms decreased significantly in the ginger group both during the trial and at a follow-up seven days later. No side effects were observed in the women or their fetuses. The previous study had warned of theoretical damage to fetal brain development, but this study’s treatment period was short – just four days – and the dosage of 1g of ginger per day is far below the amount used in many foods.

This study suggests ginger may be safe and beneficial in small doses. Other helpful measures include eating frequent small meals and taking vitamin B6 or a prescribed antiemetic. Ginger has also proven effective for treating motion sickness, seasickness,and post-surgical and chemotherapy-induced nausea.
June 2001 Update

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Ultrasound Not an Accurate Screening Test for Down Syndrome

About 5,000 babies are born each year with Down syndrome, a condition that causes varying degrees of mental disabilities and physical abnormalities. Because of the difficulties associated with raising a child with Down syndrome, some women choose to test for the condition.

The most reliable prenatal test for Down syndrome is amniocentesis, a process in which the clinician inserts a needle through the woman's abdomen to remove and analyze a sample of amniotic fluid. While the test is about 99% accurate, it increases the risk of miscarriage anywhere from 0.5-1%.

Because of the risks associated with amniocentesis, some clinicians have suggested that ultrasound should be used as a screening test to determine whether certain markers exist that suggest the baby may be born with Down's and that an amniocentesis is warranted. Ultrasound is a painless, non-invasive, general screening device that uses sound waves to view the fetus. It is widely used during the second trimester of pregnancy as a routine part of prenatal care.

While the idea of a non-invasive prenatal test is encouraging, ultrasound is not an accurate method of screening for Down syndrome, according to a study in the Journal of the American Medical Association. The analysis of 56 studies published between 1980 and 1999 found that only one of the markers found on an ultrasound, a thickening at the back of the neck, was reliable enough for a physician to recommend amniocentesis. Other markers present on an ultrasound, such as brain cysts and bright spots on the bowel, were often harmless and not reliable indictors of Down syndrome. The researchers concluded that the dangers associated with an amniocentesis based on most ultrasound markers are greater than the possibility of having a child born with Down's.
May 2001 Update

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Study Shows Fish Consumption Protects Against Stroke, But FDA Suggests Pregnant Women Should Take Caution

A large study in the Journal of the American Medical Association (JAMA) recently showed that regularly eating fish might protect against ischemic stroke, which is the most common type of stroke. Numerous studies have already shown an association between fish consumption and a reduced risk of heart disease. But there is a caveat. The Food and Drug Administration (FDA) recently warned that pregnant women and women who are of childbearing age who may become pregnant, should avoid certain types of fish that contain high levels of mercury, which may be harmful to their unborn children.

Results of the Nurses' Health Study, published in the JAMA article, involved nearly 80,000 women. It showed that women who ate fish two to four times a week had a 48% lower risk of ischemic stroke — the kind caused by blood clots — than women who ate fish less than once per month. Even women who ate fish only once a week or less had a risk reduction, but it was not statistically significant. These results held true primarily among women who did not regularly take aspirin, which prevents the formation of blood clots. Omega-3 fatty acids, the protective substances found in fish, reduce levels of fats related to cardiovascular disease and help prevent blood clotting. Dark, oily fish such as mackerel, salmon, and sardines are a good source of omega-3 fatty acids.

Although pregnant women need not give up fish — and its beneficial health effects — altogether, they should be careful about what types of fish they eat. The FDA has advised that pregnant women and those who may become pregnant stop eating shark, swordfish, king mackerel, and tilefish. These large, long-living fish contain hazardous levels of methyl mercury, a form of mercury that can accumulate in a woman's body and affect the developing central nervous system of an unborn child. This can lead to babies with slower cognitive development. As an extra precaution, the FDA advised that nursing mothers and young children also avoid these fish. Mercury gets into both fresh and salt water through industrial pollution.

Some critics feel the FDA's mercury warnings are not strong enough. A report by the National Academy of Sciences suggested the exposure limits for mercury should be four times stricter.

While this controversy remains unresolved, the FDA encouraged pregnant women to continue to eat a variety of other fish, containing very low levels of mercury, as part of a balanced diet. Among other health benefits, the fatty acids in fish enhance brain development. According to the FDA, women can safely eat up to 12 ounces of fish per week. Fish that contain low levels of mercury include shellfish, canned fish, smaller ocean fish, and farm-raised fish. Women who eat fish caught by family or friends should contact their local health department for advice on the safety of fish from local waters.
May 2001 Update

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Does Aspirin Prevent Preeclampsia?

Preeclampsia, also known as toxemia, is a condition that affects pregnant women and their unborn baby. It is characterized by high blood pressure, water retention, and protein in the urine. The condition, which usually occurs after the 5th month of pregnancy, can lead to seizures, kidney and liver damage, slow fetal growth, and even fetal or maternal death. Preeclampsia affects up to 8% of pregnancies, and is responsible for 10-15% of maternal deaths. In the past decade, several studies have looked at the effectiveness of aspirin in preventing preeclampsia.

Early studies showed promising results. But larger, more recent studies failed to show any benefit.

In an effort to reconcile these conflicting results, British researchers reviewed several studies involving over 30,000 women who were at increased risk for preeclampsia. (Risk factors include preexisting high blood pressure, diabetes, a first pregnancy, pregnancy as a teenager or over the age of 40, and pregnancy involving multiple fetuses.) The women had been randomized to receive an antiplatelet drug (usually low-dose aspirin), a placebo, or no antiplatelet medication.

The researchers concluded that aspirin reduced the risk of preeclampsia by 15%. Their review also showed that aspirin decreased the risk of premature births by 8% and the risk of stillbirths or newborn deaths by 14%. Based on these results — acknowledged by the researchers as showing only small to moderate benefits — the researchers recommended the use of aspirin. Several issues including the optimal dosage, the proper time to start treatment, and which women are most likely to benefit, remain unresolved.

Despite the results of this review, some leading experts are unconvinced that aspirin is effective at preventing preeclampsia. However, even physicians who doubt aspirin's efficacy agree that at doses of less than 80 milligrams per day, aspirin is not harmful. If your physician prescribes aspirin to prevent preeclampsia, it may or may not be effective — but in any case, it won't be harmful.
March 2001 Update

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Caffeine Intake Linked to Miscarriage in Early Pregnancy

Many doctors urge women to limit or avoid caffeine intake during pregnancy because of a suspected link between caffeine and miscarriage. A recent study published in the New England Journal of Medicine adds weight to the cause and effect relationship. The study showed that the amount of caffeine found in one to three cups of coffee increases the risk of miscarriage by 30 percent. Three to five cups a day increases risk by 40 percent, and five or more cups of coffee per day more than doubles the risk of miscarriage.

The researchers collected data from 562 women in Sweden who had had a miscarriage during their first trimester of pregnancy and from 953 women who did not miscarry. They questioned the women about their caffeine intake as well as symptoms of pregnancy such as nausea, vomiting and tiredness. They also performed additional tests to separate risk of smoking and of genetic defects of the fetus from the risk associated with caffeine intake. Even after accounting for these factors, they found that caffeine increases risk of miscarriage. Although coffee is usually a primary source of caffeine, the study suggests that caffeine found in tea, soda, and other sources can also lead to miscarriage, if taken in comparable amounts.

Previous studies have been unable to separate the role of nausea from the role of caffeine intake in relation to miscarriage. Nausea and vomiting, which are more common in healthy pregnancies, naturally limit the amount of coffee ingested. As a result, it has been difficult to establish whether these women carried to term because they limited their intake of caffeine or because their pregnancies were healthier to begin with. The researchers in this study found a relationship between caffeine and miscarriage even after controlling for nausea.
January 2001 Update

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Hormone Level Best Predictor of Drug Success in Treating Ectopic Pregnancy

The prevalence of ectopic pregnancies has risen sharply since the 1970s. Some women are at increased risk for an ectopic pregnancy — for example, women who smoke, or have had prior pelvic surgery, or have used an IUD in the past, and those with a history of infertility. An ectopic pregnancy occurs when an embryo starts to develop outside the uterus, usually in a fallopian tube. This quirk of nature is difficult. The embryos are rarely normal, and it is impossible for the pregnancy to continue. This situation also threatens a woman's health. If an ectopic pregnancy goes undetected, the fallopian tube could rupture and the woman could suffer severe internal bleeding. If it is not detected early enough, there can be damage to the woman's reproductive organs that can compromise her fertility. Symptoms of an ectopic pregnancy may include vaginal bleeding, sharp abdominal cramps, or pains on one side; however, ectopic pregnancy can be painless or associated with only mild cramps.

An ectopic pregnancy is generally treated with surgery, which is invasive and carries certain risks. Another approach is the use of a drug called methotrexate. Methotrexate is traditionally used as part of cancer therapy because it obstructs the metabolism of rapidly growing cells. In the case of an ectopic pregnancy, the drug prevents embryonic cells from multiplying. While there are clear advantages to medical treatment of an ectopic pregnancy (no surgical risks, faster recovery time, and possibly better preservation of fertility), it isn't always effective and sometimes surgery is required.

Researchers from the University of Tennessee, Memphis, recently did a study to determine what factors might help predict whether methotrexate treatment will be successful. They monitored 350 women with ectopic pregnancies who were given the drug; 320 of the women were treated successfully. After comparing various factors, such as the size of the embryo and the presence of fluid in the abdominal cavity, the researchers determined that the level of a hormone produced during pregnancy was the single most important factor in determining whether drug treatment would be successful. The hormone, called human chorionic gonadotropin (HCG), is produced by the placenta and helps ensure the production of progesterone, thus preserving the pregnancy. (It is the hormone measured in home pregnancy tests.) High levels of the hormone suggest an embryo that is still developing and growing. Methotrexate treatment was more successful in women whose HCG levels were 15,000 or less. It is important to keep in mind that the women in this study had very early ectopic pregnancies and no signs of internal bleeding.

Ectopic pregnancy can be a painful experience both emotionally and physically. Medical treatment with methotrexate, rather than surgery, can be a somewhat less traumatic way to handle this problem.

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Breast-Feeding May Protect Against Childhood Asthma

Another vote in favor of breast-feeding! Researchers in Western Australia found that babies who are fed breast milk exclusively for their first four months are less likely to develop asthma by age 6. Asthma is the leading cause of hospital admissions for Australian youth. In the United States, it affects about 17 million Americans and about a quarter of all children under 18.

To determine whether there was a connection between asthma and breast-feeding, the researchers compared questionnaires completed by parents when their children were a year old with questionnaires completed when the children were 6. The surveys asked about breathing problems, feeding (length and exclusivity of breast-feeding), smoking in the home, and daycare (to evaluate exposure to respiratory infections).

The age at which a child was fed soy or cow's milk was more positively associated with asthma and wheezing. Introduction of milk other than breast milk before four months was a significant risk factor for the development of asthma by age 6. According to the Food and Drug Administration, babies who are breast-fed have lower rates of hospital admissions, ear infections, diarrhea, rashes, allergies, and other medical problems than bottle-fed babies. Because human milk contains cells that kill bacteria, fungi, and viruses, breast-fed babies are protected from a number of illnesses. To learn more about breast-feeding, see page 951 of the Family Health Guide. If you are unable to breast-feed, see page 505 for more information about other ways to prevent childhood asthma. Controllable risk factors include the presence of house dust and tobacco smoke.

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Thyroid Deficiency During Pregnancy

Researchers have long noted that low thyroid function (hypothyroidism) during pregnancy is associated with neuropsychological development problems in babies. A recent study published in the New England Journal of Medicine has shown that, in fact, hypothyroidism in pregnant women can negatively affect their children's performance on neuropsychological tests. And in fact, this effect may be noted even when a woman's thyroid function is only slightly below normal and without symptoms.

This research suggests that it may be worthwhile to test thyroid function in all pregnant women. Treating a woman for this condition will not only benefit her baby, but may also help women with unrecognized hypothyroidism who have no symptoms yet. 64% of the women in this study who had undiagnosed low thyroid function during pregnancy were shown to have developed confirmed hypothyroidism at follow-up 11 years later. While testing all pregnant women for low thyroid function is not yet standard practice, this research suggests that it may be in the future. If you are pregnant and have concerns about this information, talk with your doctor.

If you are a woman and you know you have low thyroid function and are of childbearing age, be sure to work closely with your doctor to keep your condition under control. If you do become pregnant, this becomes even more important. For more information on low thyroid function, see page 848 in the Family Health Guide.

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Less Painful Newborn Circumcision

Each year, millions of newborn males undergo circumcision. Their facial expressions and crying indicate that circumcision causes immense pain, yet many physicians do not administer anesthesia or pain medication for this procedure. In part, this is because many doctors are unfamiliar with the use of such medications in infants and are concerned about possible side effects.

A number of interventions can help reduce the pain of circumcision. Dorsal penile nerve block (DPNB), lidocaine-prilocaine cream (a mixture of local anesthetics), sucrose, and acetaminophen are each individually safe and effective but do not completely eliminate pain in all infants. Another approach is to use the Mogen clamp, which is associated with less pain than the Gomco clamp.

In an effort to minimize the pain of circumcision, researchers conducted a study on 86 infant males to assess the efficacy and safety of a combination of interventions. Fifty-seven infants were circumcised using the Mogen clamp and a combination of analgesics that included acetaminophen, lidocaine-prilocaine cream placed on the penis, gauze embedded with sugar and dipped in grape juice placed in the mouth, and an injection of DPNB. Researchers videotaped the infants during the procedure and assessed pain by analyzing facial activity and the percentage of time spent crying. The researchers compared the results with data from a previous study in which 29 infants were circumcised using the Gomco clamp and lidocaine-prilocaine cream.

Results from this study suggest that circumcision with the Mogen clamp took less time than circumcision with the Gomco clamp did (mean time of 55 seconds compared to 9 minutes, 37 seconds). Infants in the combination group had less facial activity indicating pain and cried for a smaller percentage of time than the infants in the single intervention group did. Furthermore, 46% of the infants in the combination group did not cry at all during the procedure and 12% cried less than 10% of the time. Infants in the combination group did not experience any adverse effects. Facial activity and crying was not eliminated in all infants treated with the combination of interventions, yet researchers do not know if these responses were due to the pain of the procedure or the discomfort of restraint. This study demonstrates that circumcision with the Mogen clamp and combined analgesia is safe, takes less time, and substantially minimizes pain. Parents of male infants and the physicians performing circumcisions should consider this approach.

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Pregnancy and the Risk of Blood Clots

Of all the complications that may occur during pregnancy, clots that obstruct blood vessels are the leading cause of death in pregnant women. Still, such occurrences are relatively uncommon. How do you know if venous thrombosis, as the condition is called, is something that you should worry about? How do you know if drug treatment is necessary? Researchers are trying to answer these questions.

In Germany, physicians conducted a study to determine the risk of clots associated with certain genetic and protein factors in pregnant women. The researchers collected and analyzed blood samples from women with a history of blood clots during or after pregnancy. These samples were compared to blood samples from women who did not experience these problems. According to the results, women with normal genetic and protein factors had only a 0.03% risk of formation of blood clots. The findings also showed that two genetic abnormalities, known as G20210A prothrombin-gene mutation and factor V Leiden, are individual risk factors for blood clots, increasing the risk of blood clots to 0.5% and 0.25%, respectively. In addition, a woman who has both variations has a greater probability of experiencing blood clots during pregnancy (4.6%). However, only 9.3% of the women with a history of blood clots had both genetic variations. Women with deficiencies in proteins that prevent blood clotting were also at increased risk for this complication during pregnancy (0.4% probability).

The results do not suggest that every pregnant woman should be screened for the genetic variations associated with blood clots. Rather, women who have a personal or family history of problems due to blood clots should discuss the need for screening with their obstetrician. Treatment is available to help prevent the formation of blood clots in women who are at an increased risk.

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