Pregnancy myths! Q&A with Dr. Laurie Green
- Can you predetermine your baby's gender with intercourse timing?
NO. An intricate 1995 study used maternal hormone levels to identify the precise day of ovulation. Intercourse timing had no influence on the baby's gender. The study did produce a surprising finding: 6% of the pregnancies resulted from sperm greater than 3 days old; and, most surprisingly, women are most fertile the day they ovulate and the 2 days prior. Once the egg leaves the ovary, it has a short life expectancy. Previously it was believed that it stayed alive and could be fertilized for at least 24 hours after ovulation. Not so!!!!
- Is it important to take prenatal vitamins before conception?
YES AND NO. Women who eat a balanced diet and supplement with a small dose of folic acid should be fine. Otherwise, starting a prenatal vitamin 3 months ahead of time is a reasonable idea. These vitamins contain iron and calcium, both of which can be constipating. Flour in the US is fortified with folic acid, so there are many dietary sources.
- Once I am pregnant can I...
>> Have my teeth cleaned?
YES. when teeth are cleaned or even brushed, a shower of bacteria can enter the bloodstream, but this generally causes no harm. Gums swell and grow during pregnancy, predisposing women to gum disease and even more bacteria harboring under the swollen tissues, so clean teeth from the start limits that bacterial growth.
>> Color my hair?
YES. Some women want to avoid doing so in the first trimester.
>> Have my nails painted?
YES. Some women in early pregnancy find the smells of a nail salon difficult to take.
>> Go through airport checkpoints and be near microwave ovens?
YES. The airport does use x-rays but rather metal detectors which are viewed to be safe, and microwave ovens are quite insulated.
>> Stop laser hair removal?
Probably YES. hair grows rapidly during pregnancy, and skin becomes more vascular and easier to inflame and therefore infect. Also, skin hyperpigments in pregnancy due to hormones and any skin irritants can cause brown splotches. This holds true for acid skin treatments too: blemishes may lessen but pigment might increase.
- Can I eat fish? Coldcuts? Soft Cheese? Can I have coffee or alcohol?
It is generally recommended that women avoid big fish that might have a higher mercury content. This includes swordfish, sea bass, tuna, mackerel, but allows women to eat trout, scallops, clam, crab, salmon.
The worry with coldcuts is a bacteria called listeria. This is quite rare, so I allow my patients to eat deli-prepared foods but veer away from those in dated packs as opposed to recently cooked meats. Any cheese is fine as long as it has been pasteurized.
Although there are many conflicting studies regarding caffeine, I feel quite comfortable with patients ingesting up to 200mg/day. That would mean keeping the intake below 2 cups of regular coffee a day, or 6 cans of soda.
Alcohol is best avoided: we suspect that fetal alcohol syndrome, a series of severe abnormalities, is dose-exposure related, but we will never be able to prove that some cases aren't idiosyncratic, ie, any alcohol exposure triggers the syndrome. Adding to this concern is that mothers of fetal alcohol syndrome babies often report unremarkable amounts of alcohol intake when interviewed postpartum. This probably represents failed recall, but caution is best.
- Do I really need to eat for two?
NO. There's great concern in the public health community that women are developing diabetes, hypertension, and obesity because of excess weight gain in pregnancy that can't easily be lost. Eat a balanced diet, eliminate junk food, but keep close to your normal calorie intake. Some women add milk to their diet...yet a quart of milk adds 500 calories to one's daily intake that would be excessive unless something is excluded from the diet. In the late third trimester, a woman needs about 200-300 calories above her norm.
- Can I go into a sauna or hot tub?
NO. It is fine to take a fairly warm of even hot bath, but you should not go into water with a very high (greater than 100) temperature.
- Can I sleep on my back?
YES YES YES. One of the most pervasive myths, found in almost all pregnancy books, is that women must sleep on the left side. This is simply untrue. When the uterus is large enough to press on the blood vessels in the abdomen, women spontaneously and quite naturally stop sleeping flat. 5 degrees tilt off the horizontal is not considered 'on the back', so women who are more comfortable on their backs may stay there as long as they aren't lying flat.
- Can I ski during pregnancy?
NO. Besides the risk of falling and hitting the uterus, women who are pregnant form blood clots very readily...so a woman who falls and immobilizes her leg has a 9x greater risk of developing a blood clot in the leg that can travel to the lungs than a non-pregnant woman. Also, exercises involving balance become difficult after the half-way point of pregnancy, because the brain is balancing a body that isn't the same.
- What creams can I use to avoid stretch marks?
NONE. Stretch marks derive from an area of skin called the dermis, located so deep below the surface that none of the topical creams penetrate. Several studies of cocoa butter and other salves have not yielded positive results.
- How much fetal movement should I feel, and why do my friends feel more than I do?
Fetal movement depends upon the position of the baby, the location of the placenta, and the size of the baby. It first begins betwen 16 and 20 weeks as an intermittent gas bubble or flutter. Between 26 and 30 weeks, babies stop doing 360's and start just moving limbs, so some women note a drop in movement--that's normal. After 30 weeks, a pattern is usually established. Most important is the baby's internal clock, not how the baby compares to prior pregnancies. The placenta can implant anywhere in the uterus. When it rests on the front wall, it acts like a cushion so less movement is felt than when it is located on the back wall.
- Does pregnancy and nursing protect me from breast cancer?
YES AND NO. A small percentage of breast cancers are diagnosed during pregnancy or nursing, so women should perform breast self exams each month during that time. I recommend chosing your birthday each month. Women who give birth for the first time under age 20 drop their lifetime risk of breast cancer to around 1/25, but women given birth for the first time after age 34 increase their risk from 1/9 to around 1/7. Nursing has no impact on these risks.
- What can I do to get labor started?
Many myths abound, including spicy foods (NOT), sex (NOT), nipple stimulation, reflexology, acupuncture, and a pizza from an East Bay restaurant. 90% of women will start labor within a week on either side of the due date, when the date is accurate. Nothing gets it going!
- Can I have intercourse during pregnancy?
YES. Anyone with high risk of preterm labor should consult her doctor, and it's probably best to avoid intercourse within the week of the due date..some studies suggest a higher risk of uterine infection if unprotected intercourse occurs within 24 hours of the breaking of the water bag.
- Can I travel?
YES, AND NO. I ask my low risk patients to stop traveling 8 weeks before the due date. The reason is that some women do go into premature labor when away. Not only are they then prevented from flying home, but premature babies cannot be moved quickly, and often need to stay near the hospital where they were born until they reach their official due date. That could mean an extended vacation away from home!
- Is it normal to feel a bit down and overwhelmed? Should I stop my anti-depressants if I've used them, or is it safe to start anti-depressants if problems arise?
It is very normal to feel overwhelmed when facing the prospect of new parenthood. As exciting as the future may be, entering a new phase of life with a new schedule, new responsibilities, less personal freedom, and less certainty can be very challenging. Making the situation harder for some women is that high quality sleep is interrupted by pregnancy. Between trips to the bathroom and quality sleep disrupted by fetal movement, many women are exhausted. High quality sleep allows us to process our anxieties and awaken feeling rested. Pregnancy diminishes the proportion of quality sleep, which in turn leaves women feeling tired and a bit down even if it appears one has 'slept through the night'. It is generally not recommended that women stop anti-depressants without first consulting a physician. The same would be true for starting them. The important message is that we are here to help; that these feelings are common and normal, and nothing to be ashamed of. Women should share their feelings with their partners and their doctors.
